AN62 - Data Acquisition Circuit Collectioncds.linear.com/docs/en/application-note/an62.pdfAN62-1 Application Note 62 October 1994 Data Acquisition Circuit Collection Kevin R. Hoskins

AN62-1

Application Note 62

October 1994

Data Acquisition Circuit CollectionKevin R. Hoskins

INTRODUCTION

This application note features 8-, 10-, and 12-bit dataacquisition components in various circuit configurations.The circuits include battery monitoring, temperature sens-ing, isolated serial interfaces, and microprocessor andmicrocontroller serial and parallel interfaces. Also in-cluded are voltage reference circuits (Application Note 42contains more voltage reference circuits).

Additional circuit information is located in the informationreferences listed in the Circuit Index. Each informationreference refers to either an application note (example:AN42 = Application Note 42), a data sheet (example:LTC®1292 DS = LTC1292 Data Sheet), or a design note(example: DN66 = Design Note 66).

and LTC are registered trademarks and LT is a trademark of Linear Technology Corporation.

General Analog-to-Digital Application CircuitsTwo-Quadrant 150kHz Bandwidth Analog Multiplier ....................................................... Figure 1 ....... AN62-3 .................. LTC1099 DSInfinite Hold-Time Sample-and-Hold (tACQ = 240ns) ....................................................... Figure 2 ....... AN62-3 .................. LTC1099 DSFour-Quadrant 250kHz Bandwidth Analog Multiplier ....................................................... Figure 3 ....... AN62-4Demodulating a Signal Using Undersampling ................................................................. Figure 4 ....... AN62-4 .................. LTC1257 DSComplete 100ps Resolution ∆Time Circuit with “Bow” Correction .................................. Figure 5 ....... AN62-5 .................. LTC1282 DSSingle 5V 12-Bit Temperature Control System with Shutdown........................................ Figure 6 ....... AN62-6 .................. LTC1257 DSWeight Scale .................................................................................................................... Figure 7 ....... AN62-6 ......... LTC1091/2/3/4 DSAuto-Ranging 8-Channel 12-Bit Data Acquisition System with Shutdown ....................... Figure 8 ....... AN62-7 .................. LTC1257 DSAnalog-to-Digital Battery Monitoring Application CircuitsMicropower Battery Voltage Monitor .............................................................................. Figure 9 ....... AN62-8 ............... LTC1096/8 DS0A to 2A Battery Current Monitor Draws Only 70µA ........................................................ Figure 10 ..... AN62-8 ............... LTC1096/8 DSLTC1297 Data Acquisition System Micropower Battery Current Monitor ........................ Figure 11 ..... AN62-9Temperature Sensing and ConversionCurrent Output Silicon Sensor Thermometer Driving 10-Bit Analog-to-Digital

Converter Covers –55°C to 125°C with 0.2°C Resolution ........................................ Figure 12 ..... AN62-9 ......... LTC1091/2/3/4 DSThermistor-Based Temperature Measurement System Covers 20°C to 40°C

and 0°C to 100°C with 0.25°C Accuracy .................................................................. Figure 13 ..... AN62-10 ........ LTC1091/2/3/4 DSDigitally Linearized Platinum RTD Signal Conditioner ..................................................... Figure 14 ..... AN62-10 ........ LTC1091/2/3/4 DSFurnace Exhaust Gas Temperature Monitor Covers 0°C to 500°C

and Has Low Supply Detection ................................................................................ Figure 15 ..... AN62-11 ........ LTC1091/2/3/4/DSIsolated InterfacesFloating Analog-to-Digital Conversion System Powered by Capacitor Charge Pump ...... Figure 16 ..... AN62-11 .............. LTC1096/8 DSMicropower Serial 10-Bit Data Acquisition System with 500V Opto-Isolated

Communication ....................................................................................................... Figure 17 ..... AN62-12 ........ LTC1091/2/3/4 DSOpto-Isolated Temperature Monitor ................................................................................ Figure 18 ..... AN62-13 ................. LTC1292 DSBattery-Powered Digital Thermometer Transmits Over RF-Link ...................................... Figure 19 ..... AN62-13LTC1092 10-Bit Analog-to-Digital Converter Receives Power and

Transmits Data Over Two Transformer-Isolated Lines ............................................. Figure 20 ..... AN62-14 ............................ DN19

CIRCUIT INDEXINFORMATION

FIGURE TITLE FIGURE NO. PAGE REFERENCE/SOURCE

Application Note 62

AN62-2

INFORMATIONFIGURE TITLE FIGURE NO. PAGE REFERENCE/SOURCEMiscellaneous CircuitsTwo LTC1390s Cascadable Serially Programmed 8-Channel Multiplexers

Provide the Single Channel LTC1096 with 16 Analog Inputs ............................ Figure 21 ..... AN62-15Small 12-Bit Differential-Input LTC1292 Data Acquisition System Occupies

Only 0.35IN2 Including Reference and Power Supply Bypass Components ...... Figure 22 ..... AN62-15 .......................... LTC1292 DS12-Bit LTC1296 Data Acquisition System Strain Gauge with Bridge-Driver-

Power Shutdown ............................................................................................... Figure 23 ..... AN62-16 ................... LTC1293/4/6 DSLTC1282 3V Analog-to-Digital Converter with Full-Scale Adjust ............................... Figure 24 ..... AN62-16 .......................... LTC1282 DSUltra-Low Full-Scale-Drift LTC1282 3V Analog-to-Digital Converter ......................... Figure 25 ..... AN62-16 .......................... LTC1282 DSUltra-Low Full-Scale-Drift LTC1273 3V Analog-to-Digital Converter ......................... Figure 26 ..... AN62-16“Tiny” LTC1286 12-Bit Differential-Input Data Acquisition System (In SO Package)

and “Tiny” LT1019-2.5 Reference Occupies Only 0.47IN2 Including Referenceand Power Supply Bypass Components ............................................................ Figure 27 ..... AN62-17

Hardware Microcontroller InterfacesLTC1296 to Microcontroller Hardware Serial Interface .............................................. Figure 28 ..... AN62-17 ................... LTC1293/4/6 DSLTC1090 to Intel 8051 Microcontroller Hardware Serial Interface ............................ Figure 29 ..... AN62-17 .......................... LTC1090 DSLTC1090 to Motorola MC68HC05C4 Microcontroller Hardware Serial Interface ....... Figure 30 ..... AN62-17 .......................... LTC1090 DSLTC1090 to Hitachi HD63705 Microcontroller Hardware Serial Interace .................. Figure 31 ..... AN62-17 .......................... LTC1090 DSLTC1091 to Intel 8051 Microcontroller Hardware Serial Interface ............................ Figure 32 ..... AN62-18 ................ LTC1091/2/3/4 DSLTC1091 to Motorola MC68HC05C4 Microcontroller Hardware Serial Interface ....... Figure 33 ..... AN62-18 ................ LTC1091/2/3/4 DSLTC1095 to Intel 8051 Microcontroller Hardware Serial Interace ............................. Figure 34 ..... AN62-18 .......................... LTC1095 DSLTC1095 to Motorola MC68HC05C4 Microcontroller Hardware Serial Interace ........ Figure 35 ..... AN62-18 .......................... LTC1095 DSMultiple LTC1095s Sharing One Three-Wire Serial Interface .................................... Figure 36 ..... AN62-18 .......................... LTC1095 DSMultiple LTC1290s Sharing One Three-Wire Serial Interface .................................... Figure 37 ..... AN62-19 ........................... LTC1290 DSMultiple LTC1094s Sharing One Three-Wire Serial Interface .................................... Figure 38 ..... AN62-19 ................ LTC1091/2/3/4 DSInterfacing the LTC1196 to the Altera EPM5064 PLD ................................................ Figure 39 ..... AN62-19 ....................... LTC1196/8 DSSNEAK-A-BIT Circuit for the LTC1090: 11-Bit Resolution from a 10-Bit ADC ........... Figure 40 ..... AN62-20 .......................... LTC1090 DSPC Serial Interface CircuitsLTC1094 Analog-to-Digital Converter RS232 Serial Interface Using the

LT1180A Dual Driver/Receiver ........................................................................... Figure 41 ..... AN62-20 .................................... DN 29LTC1290 to IBM PC Serial Port ................................................................................. Figure 42 ..... AN62-21 .................................... DN 35Parallel Interface CircuitsLTC1272/LTC1273/LTC1275/LTC1276 to 8085A/Z80 Microprocessor

Hardware Parallel Interface ................................................................................ Figure 43 ..... AN62-21 .... LTC1272/LTC1273/5/6 DSLTC1272/LTC1273/LTC1275/LTC1276 to MC68000 Microprocessor

Hardware Parallel Interface ................................................................................ Figure 44 ..... AN62-21 .... LTC1272/LTC1273/5/6 DSLTC1282 to TMS320C25 DSP Processor Parallel Interface ...................................... Figure 45 ..... AN62-22 .......................... LTC1282 DSLTC1272/LTC1273/LTC1275/LTC1276 to TMS32010 DSP Processor

Parallel Interface ................................................................................................ Figure 46 ..... AN62-22 ..... LTC1272/LTC1273/5/6 DSLTC1278 to TMS320C25 DSP Processor Parallel Interface ...................................... Figure 47 ..... AN62-22Reference CircuitsLT1034-2.5 2.5V Voltage Reference .......................................................................... Figure 48 ..... AN62-22 ............................. LT1034 DSBattery-Powered LT1004-2.5 2.5V Voltage Reference ............................................... Figure 49 ..... AN62-22 ............................ LT1004 DSLT1431Z 2.5V Voltage Reference (3-Pin Package) .................................................... Figure 50 ..... AN62-23 ............................ LT1431 DSLT1431 2.5V Voltage Reference (8-Pin Package) ...................................................... Figure 51 ..... AN62-23 ............................ LT1431 DSLT1431Z 5V Voltage Reference (8-Pin Package) ....................................................... Figure 52 ..... AN62-23 ............................ LT1431 DSLT1027 12-Bit Accurate 5V Voltage Reference Supplying Input Voltages

to the LTC1290’s VREF and VCC Pins .................................................................. Figure 53 ..... AN62-23 ............................ LT1027 DSAdjustable ReferencesLT1021-5 Adjustable 5V Voltage Reference .............................................................. Figure 54 ..... AN62-23 ............................ LT1021 DSLT1009 2.5V Voltage Reference with ±5% Trim Range ............................................ Figure 55 ..... AN62-23 ............................ LT1009 DS

AN62-3

Application Note 62

GENERAL ANALOG-TO-DIGITAL APPLICATION CIRCUITS

INFORMATIONFIGURE TITLE FIGURE NO. PAGE REFERENCE/SOURCE

–

+

NC

5V

3MHZ OSC

OUTCLK

N/C

74LS90

0.1µF

0.1µF

4.7µF

0.1µF 10µF

0.1µF

1

2

3

4

5

6

7

14

13

12

11

10

9

8

÷10 = 300kHz

5V

(VIN) 0V TO 5V ANALOG INPUT

5VREF15VIN

(VIN2) +10V TO –10V ANALOG INPUT

1

2

3

4

5

6

7

8

9

10

1

2

3

4

5

6

7

8

9

10

11

12

DB0

DB1

DB2

DB3

WR/RDY

MODE

RD

INT

GND

OUT

AGND

DB7

DB6

DB5

DB4

CS

REF+

REF–

20

19

18

17

16

15

14

13

12

11

24

23

22

21

20

19

18

17

16

15

14

13

5V VCC

CS

WR1

GND

DI5

DI4

DI3

DI2

DI1

DI0

VREF

RFB

5V

NC

LTC1099

LT1019-5

CS AND RD LOW

4 DB0 TO DB3

DAC 12084

DB4 TO

DB7

= ANALOG GROUND

= DIGITAL GROUND

= BUS

8 12V

812

34 5

67

25k

15 15V

OUTPUT

–15V

50k OFFSET NULL 15V

10pF

LT1122

AN62 F01

WR2

XFER

DI6

DI7

DI8

DI9

DI10

DI11

IOUT2

IOUT1

BYTE1/ BYTE2

+

VIN1

7DB7

DB6

DB5

DB4

DB3

DB2

DB1

DB0

LTC1099

AM6012

B1

B2

B3

B4

B5

B6

B7

B8

17

16

15

14

5

4

3

2

18

3LT1122

4

7

6

2

19

–15V

1715

201412 20

1

2

3

4

5

6

7

8

6

8

13

10 11

SAMPLE

HOLD

AN62 F02

REF +

10k

2.5k

10k

V+

15V5.000V

REF– V–

IO

VOUT

IO

Figure 2. Infinite Hold Time Sample-and-Hold (tACQ = 240ns)

Figure 1. Two-Quadrant 150kHz Bandwidth Analog Multiplier

AppendicesAnalog-to-Digital/Digital-to-Analog Converter Selection Guides .................................. Appendix A ...... AN62-24Voltage Reference Selection Guide .............................................................................. Appendix B ...... AN62-28

Application Note 62

AN62-4

AIN LTC1275D11

D0

455kHz AMPLITUDE

MODULATED INPUT

RD RD

–5V

227.5kHz SAMPLE RATE

5V

AN62 F04a*

DATA OUTPUT

Figure 4. Demodulating a Signal Using Undersampling

1

2

19

22

18

20

21

24

23

3

17

12

4

5

6

7

8

9

10

11

13

14

15

16

10

13

14

11

12

21

22

21

CS

23

24

3

15

16

17

18

19

20

4

5

6

7

8

9

AIN

VREF

CONVST

BUSY

SHDN

RD

CS

AVDD

VSS

AGND

DVDD

DGND

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

VREF

IOUT1

IOUT2

RFB

GND

XFER

WR2

WR1

CS

BYTE1/BYTE2

VCC

GND

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

–5V ≤ VIN1 ≤ 5V

SAMPLE CLOCK (fSAMPLE ≤ 500kHz)

VA+ = 5V

VA– = –5V

VD+ = 5V

VA+ = POSITIVE ANALOG SUPPLY VOLTAGE

VA– = NEGATIVE ANALOG SUPPLY VOLTAGE

VD+ = DIGITAL SUPPLY VOLTAGE

LTC1278

0.1µF

0.1µF

0.1µF

VOUT

15V

AN62 F03

15V

–15V

–

+LT1122

0.1µF

0.1µF

10µF

0.1µF

0.1µF

DAC1208

–10V ≤ VIN2 ≤ 5V

= ANALOG GROUND

= DIGITAL GROUND

+

Figure 3. Four-Quadrant 250kHz Bandwidth Analog Multiplier

5µs/DIVAN62 F04b

455kHzAM SIGNAL

MODULATEDBY –6dB, 5kHz

SINEWAVE

DEMODULATED5kHz OUTPUT

SINEWAVE1V/DIV

1V/DIV

AN62-5

Application Note 62

VSS GND

AIN

REFOUT VDD

LTC1282

CS RD BUSY

12-BIT DATA OUTPUT

10µF

20k

200k

250pF POLYSTYRENE

430Ω

65Ω

3.3V

74HC03

65Ω

45.3Ω

45.3Ω

1N457

LM134

D

CLK

Q

QCLR

D

CLK

Q

QCLR

1k3.3V

3.3V

START↑

3.3V

STOP↑

DATA LATCH SIGNAL

10µF

1k

5V

100k

1N4148

0.001µF

10k

1N457

74HC74

10pF

1k 1N4148

100pF

10k

AN62 F05a

+

+

2N5771

2N23692N2369

RAMP 500mV/DIV

50ns/DIVTHE PHOTO SHOWS THE START, STOP AND RAMP WAVE-FORMS FOR A HALF SCALE, 200ns INPUT. THE RAMP REACHES2.5V IN 400ns FOR A FULL-SCALE ADC INPUT. THE 4096CODES SPREAD OVER 400ns EQUATE TO 100ps PER LSB.

AN62 F05c

STOP 5V/DIV

START 5V/DIV

Figure 5. Complete 100ps Resolution ∆Time Circuit with “Bow” Correction

∆TIME (ns)0

∆TIM

E LI

NEAR

ITY

ERRO

R (n

s)

1.0

0.8

0.6

0.4

0.2

0

–0.2

–0.4

–0.6

–0.8

–1.0400

AN62 F05b

100 200 300 500

Application Note 62

AN62-6

AN62 F06

µP

CLK

LOAD

DOUTGND

VCCVREF

VOUT LTC1257 DAC

CS

DOUT

CLK

VCC–IN

+IN

GND

5V

LTC1297 ADC

10µF

VREF

1µF

10k100k

–

+100k

47k

0.1µFVIN

GND COMM

LT1025A

1µF

1k

1µF

–+

2N3906

LTC1050

74k

CONTROL OUTPUT

DAC LOAD

DATA

CLK

CS/ POWER DOWN

DIN

J

+

Figure 6. Single 5V 12-Bit Temperature Control System with Shutdown

Figure 7. Weight Scale

NCI 3220 SCALE PLATFORM1k

VIOLET

BLACK, BLUE

FS ADJ

4.7µF

4.7µF

2µF

2k 9.09k

2.15M

2.15M2k

3

7

6.2Ω 4.75k

AN62 F07

5.23k

5V

5V

S1

8 5

64

2

1

1k

10k GREEN–

WHITE+

RED, YELLOW

MC68HC05PB0

PC2 MISO SCK

PA7

CLK

DOUT

MOTOR DRIVER

–

+

+

+

–

+LT1013

LTC1092

LT1013

CS

AN62-7

Application Note 62

AN62 F08

CLK

LOAD

DOUTGND

VREFVCC

VOUT

µP

DAC2 LTC1257

NOTE: THE µP SETS THE LTC1296’s FULL-SCALE AND ZERO-SCALE MAGNITUDES WITH THE CODE APPLIED TO DAC1 AND DAC2, RESPECTIVELY.

CLK

LOAD

DOUTGND

VREFVCC

VOUTDAC1

LTC1257

CS

DOUT

CLK

DIN

VCCCH0

CH7

COM

REF+ SSOREF–

5V22µF

8 ANALOG INPUT CHANNELS

74HC04

50k50k5V

0.1µF

100Ω

0.1µF

100Ω

0.1µF

LTC1296

DIN

DIN

2N3906

+

Figure 8. Auto-Ranging 8-Channel 12-Bit Data Acquisition System with Shutdown

Application Note 62

AN62-8

–

+

–

+

0.2Ω FOR 2A FULL SCALE 0.2Ω FOR 0.2A FULL SCALE

1/2 LT1178

1/2 LT1178

750k

73.2k

24.9k

3V TO 6V

0.1µF

0.1µF

TO µP

AN62 F10

750k

470k

470kLT1004-1.2

L O A D

LO BATTERY

LTC1096

CS

+IN

–IN

GND

VCC

CLK

DOUT

VREF

Figure 10. 0A to 2A Battery Current Monitor Draws Only 70µA

–IN

75k

3Ω

+INVCC

VREF GND

LTC1096

BATTERY MONITOR INPUT 8V TO 16V

CS

CLOCK

DOUT

LT1004-1.2

3V

AN62 F09

0.1µF266k

100k

1µF

0.1µF

Figure 9. Micropower Battery Voltage Monitor

ANALOG-TO-DIGITAL BATTERY MONITORING APPLICATION CIRCUITS

AN62-9

Application Note 62

11.5k0.1µF

226Ω

LM134 OR OTHER 1µA/°K SENSOR

LT1019-2.5

5V

+ +

9V

10µF4.7µF

3Ω

AN62 F12

TO MCU

LTC1092

CS

+IN

–IN

GND

VCC

SCLK

DOUT

VREF

Figure 12. Current Output Silicon Sensor Thermometer Driving 10-Bit Analog-to-DigitalConverter Covers –55°C to 125°C with 0.2°C Resolution

TEMPERATURE SENSING AND CONVERSION

Figure 11. LTC1297 Data Acquisition System Micropower Battery Current Monitor

–

+

CS

+IN

–IN

GND

VCC

CLK

DOUT

VREF

510k 6V TO 12V

0.005Ω 2A FULL SCALE

3k

750k

0.1µF

10Ω

1/2 LTC1047

1µF

0.33µF

1N4148

5VIN

GND

L O A D

OUT

SHDN

LT1121

LTC1297

22µF TANT

0.1µF

LT1004-2.5

20M

LO BATTERY

TO µP–

+1/2

LTC1047

AN62 F11

470k

100k

+

Application Note 62

AN62-10

Figure 14. Digitally Linearized Platinum RTD Signal Conditioner

Figure 13. Thermistor-Based Temperature Measurement System Covers 20°C to 40°C and 0°C to 100°C with 0.25°C Accuracy

AN62 F14

1k

22µF TANTALUM

CH0 CH1 CH2 CH3 CH4 CH5 CH6 CH7 COM DGND

DVCC AVCC CLK CS

DOUT DIN

REF+ REF–

AGND V–

LTC1294

–

+

TO/FROM 68HC11 PROCESSOR†

15V

A2 LT1006

30.1k**

1µF

3.92M**

500k 0°C TRIM

15V

–

+A1

LT1101 A =10

15V5VOUT

10µF

500k 400°C TRIM

12.5k*12k*

1k*

+

RPLAT

* TRW-IRC MAR-6 RESISTOR – 0.1% ** 1% FILM RESISTOR † FOR MICROCONTROLLER CODE, SEE AN43, PAGE13 RPLAT = 1k AT 0°C , ROSEMOUNT #118MF

LT1027

+

+

VCC

ACLK

SCLK

DIN

DOUT

CS

REF+

REF–

V–

AGND

CHO

CH1

CH2

CH3

CH4

CH5

CH6

CH7

COM

DGND

LTC1090

–

+LT1006

10k ±10%

5k AT 25°C 20°C TO 40°C

0°C TO 100°C

15k ±10%

2N39045V

4.7µV

TO MCU

YSI 44201

YSI 44201

5k

2954Ω

4.562k

*YSI 44007 OR 44034

1.491k

AN62 F13

*

AN62-11

Application Note 62

–

+

+

–

LTC1091A

CS

CH0

CH1

GND

VCC

CLK

DOUT

DIN

1N4148

9V

LT1025A

2

8J

VIN

J TYPE GND COMMON4

48

1

2

3 7

6

5

LT1019A-52

GND4

6

+

10k

20k

47ΩLTC1052

1µF0.1µF

10µF

TO MCU

AN62 F15

0.1µF

1µF

0.33µF

3.4k 1%

1k 0.1%

178k 0.1%

0.1µF

ISOLATED INTERFACES

Figure 15. Furnace Exhaust Gas Temperature Monitor Covers 0°C to 500°C and Has Low Supply Detection

Figure 16. Floating Analog-to-Digital Conversion System Powered by Capacitor Charge Pump

100k

300Ω

DATA

4N28

10k

500k

CLK

LTC1096

VREF

VCC

CLK

1k

LT1004-2.5

+IN

–IN

ANALOG INPUT

DOUT

GND

1N5817

20k100k

0.1µF

0.022µF

47µF1N5817

5MHz

0.001µF 2kV 1N5817

75k

FLOATING SYSTEM

CHARGE PUMP

+

–VFLOAT

AN62 F16

CS

2N3904

Application Note 62

AN62-12

+

DVCC

AVCC

CLK

CS

DOUT

DIN

REF+

REF–

AGND

V–

CHO

CH1

CH2

CH3

CH4

CH5

CH6

CH7

COM

DGND

20

19

18

17

16

15

14

13

12

11

1

2

3

4

5

6

7

8

9

10

1

2

3

4

8

7

6

5

LTC1094

NC

VIN

NC

GND

NC

NC

VOUT

TRIM

LT1021-5

8 ANALOG INPUTS

0V TO 5V RANGE

TO 68HC05**

TO ADDITIONAL LTC1094s

10µF*

1Ω

150Ω

5V4N28

4N28

4N28

4N28

4N28

5V

9V

AN62 F17

1

2

6

5

4

1

2

1

2

1

2

1

2

6

10k

10k

5.1k × 3

51k

5

4

6

5

4

6

5

4

6

5

4

51k

51k

51k

10k

10k

10k

10k

51k5.1k

10k

ISOLATION BARRIER

* SOLID TANTALUM ** MC68HC05 CODE AVAILABLE FROM LINEAR TECHNOLOGY

300Ω

150Ω

150Ω

150Ω

C1

5V

SCK

5V

C0

5V

MOSI

MISO2N3904

2N39062M3906

Figure 17. Micropower Serial 10-Bit Data Acquisition System with 500V Opto-Isolated Communication

AN62-13

Application Note 62

+1 F

TYPE J

J

RGND

LT1025A

VIN 8

2

2

3LTC1050

7

4

6

+

µ

0.33 Fµ

178k 0.1%

3.4k 0.1%

2k 0.1%

47Ω

+1µF

GND

LTC1292

VCC

–IN

+IN

CS

CLK

DOUT

VREF

+4.7 Fµ

3Ω

+0.1µF

10k

1N4148

8

7

6

5

1

2

3

4

+22µF LT1019-2.5

500k

1

2 1k CLK IN

3

4

500k

3

4

5k

DATA OUT

1

2 6

1k

4N28

4N28

1N4148

0°C TO 500°C TEMPERATURE RANGE

ISOLATED 5V

4 5

+ +–

–6

100k

74C14

5V

5V5k

AN62 F18

1N4148

Figure 18. Opto-Isolated Temperature Monitor

Figure 19. Battery-Powered Digital Thermometer Transmits Over RF-Link

13.5k

15.8k

45.3k

LM134

678Ω

30k

–IN

+IN

8pF5pF

REF OUT 300MHz

*TWO TURNS OF BUS WIRE WRAPPED AROUND A PENCIL

5.1k

100k

30nH*

3V

74HC132

100k

3V

3V

0.22µF

VREF

VCC

GND

CS

CLK

DOUT

LTC1096

LT1004-1.2

CARRY

V–

V+

CLK

VDD

R

VSS

74HC161

MRF501

AN62 F19

3V

510ΩMBR0540T1

1M

10M

2M300pF

Application Note 62

AN62-14

10k74HC132

74HC132

100pF

100pF

74HC04

74HC04

74HC00

74HC04

74HC04

74HC00

74HC0010k

5.1k

75k

5k

750pF

1µF

1µF

1Ω

1µF 1µF

2000pF

VCC

1N4148

HP2810PE-2229X*

* PULSE ENGINEERING, INC. P.O. BOX 12235 7250 CONVOY COURT SAN DIEGO, CA 92112

HP2810

1k1k

51k

39pF

1

2

3

4

2

3

4

5

6

7

8

8

7

6

5

15

14

13

12

11

10

9

LTC1092

CS

+IN

–IN

GND

VCC

CLK

DOUT

VREF

74HC161

RIPPLE CARRY

OUT

CLR

CLK

A

B

C

D

ENABLE P

GND

VCC

QA

QB

QC

QD

ENABLE T

LOAD

1

16

470Ω

510pF

10k

5V

LT1021-5

1N4148

1N4148

1N4148

1N4148

10k

5V

1k1k

51k

15V5k

CLR SET Q Q

D

CLK74HC74

74HC14

74HC14

VCC

1N4148

1k

10k

CS

VCC

VCCLOAD DATA

100pF10k

VCC

VCC

AN62 F20

REXT/ CEXT1

REXT/ CEXT1

CEXT1

CEXT2

CLR2

CLR1

100pF

74HC221

Q1

Q2A1 B1

B2 A2

GND

16

5436543 13121110

7 8 MSBLSB 90 1 2 3 4 5 6

1 2 3 4 5 6 7 8

10k

88912

912

15 14 11 10 913 12Q2

Q1

10µF

CLKCLRIN AIN B

74HC164

CLKCLRIN AIN B

74HC164

2N2905

2N39041k

1k

VCC = 5V CS PULSE WIDTH = 2µs TO 6µs LOAD DATA PULSE WIDTH = 1µs fCS = 10kHz

+

Figure 20. LTC1092 10-Bit Analog-to-Digital Converter Receives Powerand Transmits Data Over Two Transformer-Isolated Lines

START BIT 9 8 7 6 5 4 3 2 1 0

AN62 F20b

DOUT

CLOCK

ENCODED OUTPUT

CS

TIMING DIAGRAM SHOWING PULSE-WIDTH CODING TECHNIQUE

AN62-15

Application Note 62

Figure 22. Small 12-Bit Differential-Input LTC1292 Data Acquisition System OccupiesOnly 0.35IN2 Including Reference and Power Supply Bypass Components

+

–

DIFFERENTIAL INPUTS COMMON-MODE RANGE

0V TO 5V1N4148

VREF

DOUT

CLK

VCC

LTC1292

+IN

GND

CS

–IN

LT1027

4.7µF TANTALUM

+

8V TO 40V

1µF

22µF TANTALUM

MC68HC11

DO

SCK

MISO

AN62 F22

+

5V

MISCELLANEOUS CIRCUITS

Figure 21. Two LTC1390 Cascadable Serially Programmed 8-Channel MultiplexersProvide the Single Channel LTC1096 with 16 Analog Inputs

1

2

3

4

5

6

7

8

CH0

CH1

CH2

CH3

CH4

CH5

CH6

CH7

16

15

14

13

12

11

10

9

LTC1390S0

S1

S2

S3

S4

S5

S6

S7

V+

D

V–

DATA2

DATA1

CS

CLK

GND

1

2

3

4

8

7

6

5

LTC1096

VCC

CLK

DOUT

VREF

CS

+IN

–IN

GND

1

2

3

4

5

6

7

8

CH8

CH9

CH10

CH11

CH12

CH13

CH14

CH15

16

15

14

13

12

11

10

9

LTC1390S0

S1

S2

S3

S4

S5

S6

S7

V+

D

V–

DATA2

DATA1

CS

CLK

GND

5V

5V

–5V

0.1µF

0.1µF

0.1µF

0.1µF

0.1µF

R

C

OPTIONAL ADC INPUT FILTER

CLK

CS

DATAAN62 F21

Application Note 62

AN62-16

Figure 23. 12-Bit LTC1296 Data Acquisition System Strain Gauge with Bridge-Driver-Power Shutdown

CH0

CH1

CH2

CH3

CH4

CH5

CH6

CH7

COM

DGND

–

+

RB 5.1k

R2 1.2M

R1 10k

1/4 LT1014

R2 1.2M

C2 1µF

350Ω STRAIN GAUGE BRIDGE

5V

47µF

1N4148

MPU

LTC1296

VCC

SSO

CLK

CS

DOUT

DIN

REF+

REF–

AGND

V–THREE ADDITIONAL STRAIN GAUGE INPUTS CAN BE ACCOMMODATED USING THE OTHER AMPLIFIERS IN THE LT1014

AN62 F23

74HC04

+

2N3906

3Ω

INPUT RANGE ±2.60V

LTC1282

AIN

AGND

VREF

10µF

AN62 F25

LT1019A-2.5

VIN

GND

VOUT

5VVDD

VSS

+

3V

–3V

Figure 24. LTC1282 3V Analog-to-Digital Converterwith Full-Scale Adjust

VREF(OUT) ≥ 1.25V

3Ω

INPUT RANGE ±1.033VREF(OUT)

–

+LT1006

10µF

AN62 F24

LTC1282

AIN

AGND

VREF

VDD

VSS

3V

–3V

Figure 25. Ultra-Low Full-Scale Drift LTC12823V Analog-to-Digital Converter

Figure 26. Ultra-Low Full-Scale Drift LTC1273 3V Analog-to-Digital Converter

3Ω

INPUT RANGE ±2.583V

LTC1273

AIN

AGND

VREF

10µF

AN62 F26

LT1019A-2.5

VIN

GND

VOUT

5VVDD

VSS

+

5V

–5V

AN62-17

Application Note 62

+

–

DIFFERENTIAL INPUTS COMMON-MODE RANGE

0V TO 5V

VCC

CLK

DOUT

CS/SHDN

1

2

3

4

6

5

3

8

7

6

5

2

7

1

4

LTC1286

VREF

+IN

–IN

GND

IN

HEATER

NC*

GND

OUT

TRIM

TEMP

NC*

SERIAL DATA LINK

*INTERNALLY CONNECTED; DO NOT CONNECT EXTERNALLY

0.1µF

NC

0.1µF

0.1µF MPU (e.g. 8051)

P1.4

P1.3

P1.2

AN62 F27

5V

LT1019-2.5

1.5M100k

Figure 27. “Tiny” LTC1286 12-Bit Differential-Input Data Acquisition System (In SO Package)and “Tiny” LT1019-2.5 Reference Occupies Only 0.47IN2 Including Reference and Power SupplyBypass Components

8 ANALOG INPUTS

CS

DIN

CLK

DOUT

LTC1296 µP

AN62 F28

Figure 29. LTC1090* to Intel 8051 Microcontroller HardwareSerial Interface

Figure 28. LTC1296 to Microcontroller HardwareSerial Interface

P1.1

P1.2

P1.3

P1.4

ALE

LTC1090 8051

DOUT

DIN

SCLK

CS

ACLK

AN62 F29

8 ANALOG INPUTS

Figure 30. LTC1090* to Motorola MC68HC05C4 MicrocontrollerHardware Serial Interface

8 ANALOG INPUTS

CS

SCLK

DIN

DOUT

C0

SCK

MOSI

MISO

LTC1090 MC68HC05C4

AN62 F30

8 ANALOG INPUTS

LTC1090 HD63705

CS

SCLK

DIN

DOUT

C0

CK

TX

RX

AN62 F31

Figure 31. LTC1090* to Hitachi HD63705 MicrocontrollerHardware Serial Interface

HARDWARE MICROCONTROLLER INTERFACES

*Increase resolution from 10 bits to 12 bits with the pin compatible LTC1290.

Application Note 62

AN62-18

Figure 36. Multiple LTC1095s Sharing One Three-Wire Serial Interface

2 1 0

SERIAL DATA

MPU

3-WIRE SERIAL INTERFACE TO OTHER PERIPHERALS OR LTC1095s

OUTPUT PORT

AN62 F36

3

3

CSLTC1095

6 CHANNELS

3

CSLTC1095

6 CHANNELS

3

CSLTC1095

6 CHANNELS

6 ANALOG INPUTS

MUX ADDRESS

A/D RESULT

CS

CLK

DOUT

DIN

P1.4

P1.3

P1.2LTC1095 8051

AN62 F34

6 ANALOG INPUTS

CS

CLK

DIN

DOUT

C0

SCK

MOSI

MISO

LTC1095 MC68HC05C4

AN62 F35

Figure 34. LTC1095 to Intel 8051 Microcontroller HardwareSerial Interface

Figure 35. LTC1095 to Motorola MC68HC05C4 MicrocontrollerHardware Serial Interface

MUX ADDRESS

A/D RESULT

CS

CLK

DOUT

DIN

CH0

CH1

P1.4

P1.3

P1.2LTC1091 8051

AN62 F32

CS

SCLK

DIN

DOUT

C0

SCK

MOSI

MISO

LTC1091 MC68HC05C4

AN62 F33

CH0

CH1

Figure 32. LTC1091* to Intel 8051 Microcontroller HardwareSerial Interface

Figure 33. LTC1091* to Motorola MC68HC05C4 MicrocontrollerHardware Serial Interface


AN62-19

Application Note 62

2 1 0

SERIAL DATA

MPU


OUTPUT PORT

AN62 F37

3

3

CSLTC1290

8 CHANNELS

3

CSLTC1290

8 CHANNELS

Figure 37. Multiple LTC1290s Sharing One Three-Wire Serial Interface

2 1 0

SERIAL DATA

MPU


OUTPUT PORT

AN62 F38

3

3

CSLTC1094

8 CHANNELS

3

CSLTC1094

8 CHANNELS

3

CSLTC1094

8 CHANNELS

3, 14, 25, 36

EPM5064

CLK

33

23

34

35

AN62 F39

VCC

+– DATA

1 37 38 39 40 41 42 44

9-13, 21, 31, 32, 43

CLK

B7

B0

ENA

–IN

GND

VCC

CLK

DOUT

+IN

CS

1

2

3

4

8

7

6

5

LTC1196

VREF

1µF

RESERVE PINS OF EPM5064: 2, 4-8,15-20, 22, 24, 26-30

DATA

CLK

12-BIT COUNTER

CSENA

EN

CLK B0-B7

8-BIT SHIFT REGISTER

8

CSENA

CLK

DATA

B0-B7

Figure 39. Interfacing the LTC1196 to the Altera EPM5064 PLD

Figure 38. Multiple LTC1094s* Sharing One Three-Wire Serial Interface


Application Note 62

AN62-20

Figure 41. LTC1094 Analog-to-Digital Converter RS232 Serial Interface Using the LT1180A Dual Driver/Receiver

PC SERIAL INTERFACE CIRCUITS

Figure 40. SNEAK-A-BIT Circuit for the LTC1090: 11-Bit Resolution from a 10-Bit ADC

VCC

ACLK

SCLK

DIN

DOUT

CS

REF+

REF–

V–

AGND

CHO

CH1

CH2

CH3

CH4

CH5

CH6

CH7

COM

DGND

LTC1090

SCK

MOSI

MISO

C0

MC68HC05C4

9V

–5V

2MHz CLOCK

0.1µF

10µFLT1201-5

OTHER CHANNELS OR SNEAK-A-BIT

INPUTS

VIN –5V TO 5V

AN62 F40

+

+

+

+

+

1 2 3 4 5 6 7 8 9

10

20 19 18 17 16 15 14 13 12 11

LTC1094

LT1180A

LT1021-5

2N3906

+

1Ω

220Ω

R 400k

C 200pF

10Ω

4.7µF

10µF

10µF

1µF

1µF

NC

NC

4.7µF

ON/OFF5V

5V (NOTE 2)

AN62 F41

DATA OUT

CLOCK IN

A/D DATA IN

6 2

+

+

D1 1N752A

4

10k

(NOTE 1) 10k

(NOTE 3)

1µF

ANALOG INPUTS

±5V RANGE

1 2 3

4 5

6

7 8 9

18 17 16 15 14 13 12 11 10

= CLEAN ANALOG GROUND

= LOGIC GROUND

NOTE 1: 10k CURRENT LIMIT RESISTORS CAN BE REMOVED IF THE INPUTS ARE GUARANTEED NOT TO EXCEED THE LT1094’s SUPPLY VOLTAGES. NOTE 2: DRIVER OUTPUTS CAN BE PARALLEL FOR GREATER CURRENT DRIVE. NOTE 3: SELECT RC = 4tCLOCK, MINIMIZE C. NOTE 4: CONNECT THE CLEAN ANALOG GROUND AND THE LOGIC GROUND TOGETHER AT ONLY ONE POINT.

AN62-21

Application Note 62

VCC

ACLK

SCLK

DIN

DOUT

CS

REF+

REF–

V–

AGND

CHO

CH1

CH2

CH3

CH4

CH5

CH6

CH7

COM

DGND

2

3

7

LTC1290

D

↑CLK

GND

5

6

74C74

8 ANALOG INPUTS

0V TO 5V

R6 100k

2174C14

R1 22k

C1 50pF

10k

6 2

INPUT 7.2V TO 40V

V+ (UNREGULATED)

4

1110

CLR

56

1

14, 13, 12, 11, 10, 4

R7 1Ω

R2 50k

VREF 5V

C4 47µF

VREF

+

C2 150µF

RS232 POWERED OPTION (LTC1090 ONLY)

+

Q

Q

1312

89

34

R3 50k

4 (DTR)

7 (RTS)

8 (CTS)

5 (GND)

LT1021-5f0SC ≅ 300kHz

D1 1N4148

D2

SCLK

DIN

DOUT

COM1 INPUT STATUS REGISTERMSB B7 X

B6 X

B5 X

B4 CTS

B3 X

B2 X

B1 X 3FE

LSB B0 X AN62 F42

COM1 OUTPUT CONTROL REGISTERMSB B7 X

B6 X

B5 X

B4 X

B3 X

B2 X

B1 RTS 3FC

LSB B0

DTR

Figure 42. LTC1290 to IBM PC Serial Port

PARALLEL INTERFACE CIRCUITS

DATA BUS

AN62 F44

ADDRESS BUS

D0

D11

R/W

DTACK

AS

A1A23

MC68000

ADDRESS DECODEEN

D0/8

D11

RD

BUSYCS

HBEN

LTC1272 LTC1273 LTC1275 LTC1276

ANALOG FRONT-END CIRCUITRY AND ADDITIONAL PINS OMITTED FOR CLARITY

DATA BUS

AN62 F43

ADDRESS BUS

D0

D7

RD

WAIT

MREQ

A0A15

Z80 8085A

ADDRESS DECODEEN

D0/8

D7

RD

BUSYCS

HBEN


LTC1272 LTC1273 LTC1275 LTC1276

A0

Figure 43. LTC1272/LTC1273/LTC1275/LTC1276 to 8085A/ Z80Microprocessor Hardware Parallel Interface

Figure 44. LTC1272/LTC1273/LTC1275/LTC1276 to MC68000Microproessor Hardware Parallel Interface

Application Note 62

AN62-22

DATA BUS

AN62 F46

PORT ADDRESS BUS

D0

D11

DEN

PA0PA2

TMS32010

ADDRESS DECODEEN

D0/8

D11

RD

CS

HBEN

LTC1272 LTC1273 LTC1275 LTC1276


DATA BUS

AN62 F45

ADDRESS BUS

D0

D16

R/W

READY

IS

A1A16

TMS320C25

ADDRESS DECODEEN

D0/8

D11

RD

BUSYCS

HBEN

LTC1282


REFERENCE CIRCUITS

DATA BUS

AN62 F47

ADDRESS BUS

D0

D15

IS

A0A16

TMS320C25

ADDRESS DECODEEN

D0D11 SAMPLE

CLOCKCONVST

BUSY

RD

CS

READY

LTC1278


Figure 46. LTC1272/LTC1273/LTC1275/LTC1276 to TMS32010DSP Processor Parallel Interface

Figure 45. LTC1282 to TMS320C25 DSP ProcessorParallel Interface

Figure 47. LTC1278 to TMS320C25 DSP Processor Parallel Interface

Figure 49. Battery-Powered LT1004-2.52.5V Voltage Reference

9V

VOUT 2.500V ±20mV TC (TYP) = 20ppm/°C 8-BIT (±2LSB) INITIAL ACCURACY 11-BIT TYPICAL ACCURACY OVER 0°C TO 70°C TEMPERATURE RANGE

LT1004-2.5

AN62 F49

300k

Figure 48. LT1034-2.5 2.5V Voltage Reference

5V

VOUT 2.500V ±40mV TC (TYP/MAX) = 20/40ppm/°C 8-BIT (±4LSB) INITIAL ACCURACY 10-BIT ACCURACY OVER 0°C TO 70°C TEMPERATURE RANGE

LT1034-2.5

AN62 F48

50k

AN62-23

Application Note 62

RLVIN


AN62 F51

(8-PIN PACKAGE)

FGND

COLLREF

SGND

V+

LT1431

RLVIN


AN62 F50

(3-PIN PACKAGE)

ANODE

CATHODEREF

LT1431Z

Figure 51. LT1431 2.5V Voltage Reference(8-Pin Package)

Figure 50. LT1431Z 2.5V Voltage Reference(3-Pin Package)

RLVIN

VOUT 5.00V ±50mV 8-BIT (±2.5LSB) TYPICAL ACCURACY

AN62 F52

FGND

COLLREF

RMID

RTOP

SGND

V+

LT1431

Figure 52. LT1431Z 5V Voltage Reference(8-Pin Package)

VOUT 5.00V ±2.5mV TC (TYP/MAX) = 2/5ppm/°C 11-BIT (±1LSB) INITIAL ACCURACY 14-BIT ACCURACY OVER 0°C TO 70°C TEMPERATURE RANGE

AN62 F54

TRIM

R2 50k

R1 27k1N4148

OUTIN

GND

LT1021-5

5V TO 35V

VOUT 2.500V ±5mV TC (TYP/MAX) = 15/25ppm/°C 9-BIT (±1LSB) INITIAL ACCURACY 10-BIT ACCURACY OVER 0°C TO 70°C TEMPERATURE RANGE

LT1009

AN62 F55

3.6k

10k* TRIM

DOES NOT AFFECT TEMPERATURE COEFFICIENT. ±5% TRIM RANGE

*

Figure 55. LT1009 2.5V Voltage Referencewith ±5% Trim Range

ADJUSTABLE REFERENCES

Figure 53. LT1027 12-Bit Accurate 5V Voltage Reference Supplying InputVoltages to the LTC1290’s VREF and VCC Pins

22µF

TO µC

8V TO 40V

ANALOG INPUTS

AN62 F53

10k

VOUT

VTRIMGND

VIN

LT1027

SCLK ACLK DOUT

DIN CS

CHO CH1 CH2 CH3 CH4 CH5 CH6 CH7 COM

LTC1290

+2.2µF

+

VCC

REF+

REF–

AGND

DGND

V–

*

±1mV TC (TYP/MAX) = 1/2ppm/°C (LT1027A, B) 12-BIT (±1LSB) INITIAL ACCURACY 15-BIT ACCURACY OVER 0°C TO 70°C TEMPERATURE RANGE

*

Figure 54. LT1021-5 Adjustable 5V Voltage Reference

Application Note 62

AN62-24

APPENDIX A

Analog-to-Digital Converter Selection GuideTOTAL MAXIMUM

PART RESOLU- UNADJUSTED SAMPLE VOLTAGE SUPPLY PKGS IMPORTANTNUMBER DESCRIPTION TION ERROR RATE SUPPLY CURRENT AVAIL FEATURES

LTC1090C,M 10-Bit, Serial I/O, A/D 10 Bits ±0.5LSB (LTC1090A) 35ksps 5V, 2.5mA J, N, S 10-Bit ADC with Built-In 8-ChannelConverter with 8-Channel Over Full 10V, Analog MUX and Sample-and-Hold.Multiplexer. Full Duplex Temperature Range or Compatible with All Microprocessors’Serial Interface. ±5V Serial Ports. Software Configuable

Bipolar or Unipolar Operation.Full Duplex Serial I/O.

LTC1091C,M 10-Bit, 8-Pin Serial I/O, 10 Bits ±0.5LSB (LTC1091A) 31ksps 5V 3.5mA J8, N8 10-Bit ADC with Built-In 2-ChannelA/D Converter with Over Full or Analog MUX and Sample-and-Hold.2-Channel Analog Multiplexer. Temperature Range 10V Compatible with All Microprocessors’

Serial Ports. Unipolar Operation.LTC1092C,M 10-Bit, 8-Pin, A/D Converter 10 Bits ±0.5LSB (LTC1092A) 38ksps 5V 2.5mA J8, N8 Separate Reference Pin Allows Reduced

with Serial Output. Over Full or Span (Down to 220mV) Operation.Temperature Range 10V Unipolar ADCs Are Performed on a

Differential Input Pair. Compatiblewith All Microprocessors’ Serial Ports.

LTC1093C,M 10-Bit, Serial I/O, A/D 10 Bits ±0.5LSB (LTC1093A) 26ksps 5V, 2.5mA J, N, S 1-Bit ADC with Built-In 6-Channel AnalogConverter with 6-Channel Over Full 10V, MUX and Sample-and-Hold. CompatibleMultiplexer. Temperature Range or with All Microprocessors’ Serial Ports.

±5V Software Configurable Bipolar orUnipolar Operation. Half DuplexSerial I/O.

µPOWER SO-8 3V OR 5V

FAST SO-8 3V OR 5V

DYNAMIC

DYNAMICDC MONITORING

5V POWERED

3V POWERED

3V POWERED

3V POWERED

5V POWERED

5V POWERED

LTC1096 – 1 CHANNEL LTC1098 – 2 CHANNEL

LTC1283 – 8 CHANNEL

LTC1090 – 8 CHANNEL LTC1091 – 2 CHANNEL LTC1092 – 1 CHANNEL LTC1093 – 6 CHANNEL LTC1094 – 8 CHANNEL LTC1095 – WITH REFERENCE

LTC1286 – 1 CHANNEL LTC1290 – 8 CHANNEL LTC1291 – 2 CHANNEL LTC1292 – 1 CHANNEL LTC1293 – 6 CHANNEL LTC1294 – 8 CHANNEL LTC1296 – 8 CHANNEL LTC1297 – 1 CHANNEL LTC1298 – 2 CHANNEL

LTC1272 – 250ksps 7572 UPGRADE LTC1273 – 300ksps 0V TO 5V INPUT LTC1275 – 300ksps ±2.5V INPUT LTC1276 – 300ksps ±5V INPUT LTC1278 – 500ksps/400ksps ±2.5V OR 0V TO 5V INPUT LTC1279 – 600ksps ±2.5V OR 0V TO 5V INPUT

LTC1285 – 1 CHANNEL LTC1287 – 1 CHANNEL LTC1288 – 2 CHANNEL LTC1289 – 8 CHANNEL

LTC1282 – 140ksps

LTC1196 – 1Msps LTC1198 – 750ksps 2-CHANNEL

MULTIPLEXEDMULTIPLEXED

WITH SHUTDOWN

COMPLETE HIGH SPEED

LT574A SECOND SOURCE

8-BIT 10-BIT 12-BIT

AN62 AF01

AN62-25

Application Note 62

TOTAL MAXIMUMPART RESOLU- UNADJUSTED SAMPLE VOLTAGE SUPPLY PKGS. IMPORTANT

NUMBER DESCRIPTION TION ERROR RATE SUPPLY CURRENT AVAIL. FEATURESLTC1094C,M 10-Bit, Serial I/O. A/D 10 Bits ±0.5LSB (LTC1094A) 26ksps 5V, 2.5mA J, N 10-Bit ADC with Built-In 8-Channel

Converter System with Over Full 10V, Analog MUX and Sample-and-Hold.8-Channel Multiplexer. Temperature Range or Compatible with All Microprocessors’

±5V Serial Ports. Software ConfigurableBipolar or Unipolar Operation.Half Duplex Serial I/O.

LTC1095C,M 10-Bit, Serial I/O, A/D 10 Bits ±0.15% FSR 26ksps 7.2V 3.7mA J 10-Bit ADC with Built-In 6-ChannelConverter with 6-Channel to Analog MUX, Sample-and-Hold, andMultiplexer and 5V Buried 10V 5V Buried Zener Reference. CompatibleZener Reference. with All Microprocessors’ Serial Ports.

Software Configurable Bipolar orUnipolar Operation. Half DuplexSerial I/O.

LTC1096C 8-Bit, 16µs, Micropower, 8 Bits ±0.5LSB (LTC1096A) 33ksps 3V 180µA, N8, S8 Single Differential Input, Sample-and-Sampling A/D Converter with Over Full to 3µA Hold with Single-Ended Inputs.Serial I/O and Differential Temperature Range 9V During Ultra-Low Power, Automatic Power-Input. Shutdown Down Mode.

LTC1098C 8-Bit, 16µs, Micropower, 8 Bits ±0.5LSB (LTC1098A) 33ksps 3V 230µA, N8, S8 2-Channel Multiplexer, Sampling ADC.Sampling A/D Converter with Over Full to 3µA Ultra-Low Power, Automatic Power-Serial I/O and 2-Channel MUX. Temperature Range 9V During Down Mode.

ShutdownLTC1099C,M 8-Bit, 2µs A/D Converter with 8 Bits ±1LSB 256ksps 5V 15mA J, N, S Built-in Sample-and-Hold Allows Direct

Built-in Sample-and-Hold. Over Full Conversion of 5VP-P Signals up toParallel Output. Temperature Range 156kHz. Pin Compatible with

ADC0820 and AD7820.LTC1196C 8-Bit, 8-Pin, Serial I/O, 600ns, 8 Bits ±0.5LSB 1Msps 3V 10mA N, S 8-Bit ADC with Built-In Sample-and-

1MHz, Sampling A/D Over Full to Hold. Compatible with All Micro-Converter with Automatic Temperature Range 6V processors’ Serial Ports. Full DuplexPower-Down. Serial I/O.

LTC1198C 8-Bit, 8-Pin, Serial I/O, 600ns, 8 Bits ±0.5LSB 750ksps 3V 10mA, N, S 8-Bit ADC with Built-In Sample-and-750kHz, Sampling A/D Over Full to 3µA Hold. Compatible with All Micro-Converter with 2-Channel Temperature Range 6V During processors’ Serial Ports. Full DuplexAnalog MUX and Automatic Shutdown Serial I/O. 2-Channel Analog MUXPower-Down. and Automatic Power-Down.

LTC1272C,M 12-Bit, 3µs, 250ksps 12 Bits ±0.5LSB Linearity, 250ksps 5V 30mA J, N, S Single Supply 12-Bit ADC with Built-InSampling A/D Converter with ±1LSB Differential (111ksps Sample-and-Hold and 250kspsParallel Output. Single 5V Nonlinearity, and ±4LSB also Conversion Rate. Built-In 2.42VSupply. Input Range: Offset Error Over Full available) Reference. Plug-In Upgrade for AD7572.0V ≤ VIN ≤ 5V. Temperature Range. Operates with or without –15V Supply

±10LSB Full-Scale Required by AD7572. Error. 72dB SINAD

and –82dB THD at fIN = 10kHz.

LTC1273C,M 12-Bit, 2.7µs, 300ksps 12 Bits ±0.5LSB Linearity, 300ksps 5V 25mA J, N, S Single Supply 12-Bit ADC with Built-InSampling A/D Converter with ±0.75LSB Differential Sample-and-Hold, Internal Clock,Parallel Output. Single 5V Nonlinearity, and ±4LSB and 300ksps Conversion Rate.Supply. Input Range: Offset Error Over Built-In 2.42V Reference.0V ≤ VIN ≤ 5V. Full Temperature

Range. ±10LSBFull-Scale Error. 70dB

SINAD and – 74dBTHD at fIN = 150kHz.

LTC1275C 12-Bit, 2.7µs, 300ksps, 12 Bits ±0.5LSB Linearity, 300ksps ±5V 25mA N, S Split Supply 12-Bit ADC with Built-InSampling A/D Converter with ±0.75LSB Differential Sample-and-Hold, Internal Clock, Parallel Output. Split ±5V Nonlinearity, and ±4LSB and 300ksps Conversion Rate. Supply. Input Range: Offset Error Over Built-In 2.42V Reference.– 2.5V ≤ VIN ≤ 2.5V. Full Temperature

Range. 70dB SINAD and –74dB THD at

fIN = 150kHz. ±10LSB Full-Scale Error.

Application Note 62

AN62-26


NUMBER DESCRIPTION TION ERROR RATE SUPPLY CURRENT AVAIL. FEATURESLTC1276C 12-Bit, 2.7µs, 300ksps 12 Bits ±0.5LSB Linearity, 300ksps ±5V 25mA N, S Split Supply 12-Bit ADC with Built-In

Sampling A/D Converter with ±0.75LSB Differential Sample-and-Hold, Internal Clock,Parallel Output. Split ±5V Nonlinearity, and ±4LSB and 300ksps Conversion Rate.Supply. Input Range: Offset Error Over Built-In 2.42V Reference.– 5V ≤ VIN ≤ 5V. Full Temperature

Range. 70dB SINADand – 74dB THD at

fIN = 150kHz. ±10LSB Full-Scale Error.

LTC1278C,I 12-Bit, 1.6µs, 500ksps 12 Bits ±1LSB Linearity, 500ksps 5V 30mA, N, S Single or Split Supply 12-Bit ADC withSampling A/D Converter with ±1LSB Differential (400ksps or 3mA Built-In Sample-and-Hold, InternalParallel Output. Input Range Nonlinearity, and ±6LSB also ±5V During Clock, and 500ksps Conversion Rate.with Split ±5V Supply: Offset Error Over available) Shutdown Built-In 2.42V Reference. Guaranteed– 2.5V ≤ VIN ≤ 2.5V; Full Temperature 70dB SINAD and –78 THD at 100kHzwith 5V Supply: Range. 70dB SINAD Input Frequency Over Temperature.0V ≤ VIN ≤ 5V. and – 74dB THD at

fIN = 250kHz. ±15LSB Gain Error.

LTC1279C,I 12-Bit, 1.4µs, 600ksps 12 Bits ±1LSB Linearity, 600ksps 5V 20mA, N, S Single or Split Supply 12-Bit ADC withSampling A/D Converter with ±1LSB Differential or 3mA Built-In Sample-and-Hold, Internal Clock,Parallel Output. Input Range Nonlinearity, and ±6LSB ±5V During and 600ksps Conversion Rate.with 5V Supply: Offset Error Over Shutdown Built-In 2.42V Reference. Guaranteed0V ≤ VIN ≤ 5V; with Split ±5V Full Temperature 70dB SINAD and –78dB THD at 100kHzSupply: – 2.5V ≤ VIN ≤ 2.5V. Range. 70dB SINAD Input Frequency Over Temperature.

and – 74dB THD atfIN = 300kHz. ±15LSB

Gain Error.LTC1282C 12-Bit, 6µs, 140ksps 12 Bits ±0.5LSB Linearity, 140ksps 3V 8mA N, S Single or Split Supply 12-Bit ADC with

Sampling A/D Converter with ±0.75LSB Differential or a 2.7V Guaranteed Minimum SupplyParallel Output. Input Range Nonlinearity, and ±4LSB ±3V Voltage. Complete with Sample-and-with Single 3V Supply: Offset Error Over Hold, Internal Clock and a 25ppm/°C0V ≤ VIN ≤ 2.5V; Full Temperature 1.2V Reference.with Split ±3V Supply: Range. 69dB SINAD – 1.25V ≤ VIN ≤ 1.25V. and – 77dB THD at

fIN = 70kHz. ±10LSBFull-Scale Error.

LTC1283C 10-Bit, 44µs, 3.3V or ±3.3V 10 Bits ±0.5LSB Linearity and 15ksps 3.3V 350µA N, S 3.3V or ±3.3V Supply 10-Bit ADC withSampling A/D Converter with ±0.5LSB Offset Error or Built-In Sample-and-Hold. 10-BitSerial Output. Input Range Over Full ±3.3V Unipolar or 9-Bit + Sign Bipolar Serialwith Split ±3.3V Supply: Temperature Range. Output. Compatible with All Micro-– 2.5V ≤ VIN ≤ 2.5V; with 3.3V processors’ Serial Ports. Full DuplexSupply: 0V ≤ VIN ≤ 2.5V. Serial I/O.

LTC1285C 12-Bit, 8-Pin Serial I/O, 12 Bits ±2LSB Linearity, 7.5ksps 3V 320µA, N, S 12-Bit ADC with Built-In Sample-and-160µA (Typ) 3V Sampling A/D ±0.75LSB Differential 3µA Hold. Operates on 3V Supply Voltage.Converter with Automatic Nonlinearity, ±3LSB During Compatible with All Microprocessors’Power-Down and Differential Offset, and ±8LSB Full- Shutdown Serial Ports. Automatic Power-Down.Analog Input. Scale Error Over Full

Temperature Range.LTC1286C,I 12-Bit, 8-Pin Serial I/O, 12 Bits ±2LSB Linearity, 12.5ksps 5V 500µA, N, S 12-Bit ADC with Built-In Sample-and-

250µA (Typ) Sampling A/D ±0.75LSB Differential to 3µA Hold. Compatible with All Micro-Converter with Automatic Nonlinearity, ±3LSB 9V During processors’ Serial Ports. AutomaticPower-Down. Offset, and ±8LSB Shutdown Power Down.

Full-Scale ErrorOver Full

Temperature Range.LTC1287C,I 12-Bit, 33µs, 3.3V Sampling 12 Bits ±0.5LSB Linearity, 30ksps 2.7V 5mA J, N, 12-Bit ADC with Built-In Sample-and-

A/D Converter with Serial ±3LSB Offset, and to Hold. Guaranteed Operation on a 2.7V Output. Input Range with ±0.5LSB Full-Scale 3.3V Supply. Compatible with All Micro- 3.3V Supply: 0V ≤ VIN ≤ 3.3V. Error Over Full processors’ Serial Ports.

Temperature Range.

AN62-27

Application Note 62


NUMBER DESCRIPTION TION ERROR RATE SUPPLY CURRENT AVAIL. FEATURESLLTC1288C 12-Bit, 8-Pin, Serial I/O, 12 Bits ±2LSB Linearity, 6.6ksps 3V 390µA, N, S 12-Bit ADC with Built-In Sample-and-

210µA (Typ) 3V Sampling A/D ±0.75 Differential 3µA Hold. Operates on 3V Supply Voltage.Converter with Automatic Nonlinearity, ±3LSB During Compatible with All Microprocessors’Power-Down, Differential Offset, and ±8LSB Full- Shutdown Serial Ports. Automatic Power-Down.Analog Input and 2-Channel Scale Error Over Full 2-Channel Multiplexer.Multiplexer. Temperature Range.

LTC1289C,I 12-Bit, 40µs, 3.3V or ±3.3V, 12 Bits ±0.5LSB Linearity, 25ksps 2.7V 5mA, J, N, S 12-Bit ADC with Built-In Sample-and-Sampling A/D Converter with ±1.5LSB Offset, and to 10µA Hold and 8-Channel MUX.8-Channel MUX and Serial ±0.5LSB Full-Scale 3.3V During Guaranteed Operation on a 2.7VOutput. Input Range with Error Over Full or Shutdown Supply. Compatible with All Micro-Split ±3.3V Supply: Temperature Range. ±2.7V processors’ Serial Ports. Automatic– 3.3V ≤ VIN ≤ 3.3V; with 3.3V to Power-Down. Supply: 0V ≤ VIN ≤ 3.3V. ±3.3V

LTC1290C,I,M 12-Bit, 8-Pin Serial I/O, 12 Bits ±0.5LSB Linearity, 50ksps 5V 12mA J, N, S 12-Bit ADC with Built-In 8-ChannelA/D Converter with 8-Channel ±1.5LSB Offset, and or Analog MUX and Sample-and-Hold.Multiplexer. Full Duplex ±0.5LSB Full-Scale ±5V Compatible with All Microprocessors’Serial Interface. Error Over Full Serial Ports. Software Configurable

Temperature Range. Bipolar or Unipolar Operation. FullDuplex Serial I/O.

LTC1291C,I,M 12-Bit, 12µs, 5V, Sampling 12 Bits ±0.5LSB Linearity, 54ksps 2.7V 12mA, J, N 12-Bit ADC with Built-In Sample-and-A/D Converter with Serial ±3LSB Offset, and to 10µA Hold. Compatible with All Micro-Output. Input Range: ±1LSB Full-Scale 3.3V During processors’ Serial Ports. Automatic0V ≤ VIN ≤ 5V. Error Over Full or Shutdown Power-Down.

Temperature Range. ±3.3VLTC1292C,I,M 12-Bit, 8-Pin A/D Converter 12 Bits ±0.5LSB Linearity, 60ksps 5V 12mA J, N 12-Bit ADC, Unipolar Conversion of

Serial Output. ±3LSB Offset, and Single Differential Input. Separate±0.5LSB Full-Scale Reference Pin Allows Reduced Span.

Error Over Full Compatible with All Microprocessors’Temperature Range. Serial Ports.

LTC1293C,I,M 12-Bit, Serial I/O, 12 Bits ±0.5LSB Linearity, 46ksps 5V 12mA J, N 12-Bit ADC with Built-In 6-ChannelA/D Converter System with ±3LSB Offset, and or MUX and Sample-and-Hold.6-Channel Multiplexer. ±0.5LSB Full-Scale ±5V Compatible with All Microprocessors’

Error Over Full Serial Ports. Software ConfigurableTemperature Range. Bipolar or Unipolar Operation.

Full Duplex Serial I/O.LTC1294C,I,M 12-Bit, Serial I/O, 12 Bits ±0.5LSB Linearity, 46ksps 5V 12mA J, N 12-Bit ADC with Built-In 8-Channel

A/D Converter System with ±3LSB Offset, and or MUX and Sample-and-Hold.8-Channel Multiplexer. ±0.5LSB Full-Scale ±5V Compatible with All Microprocessors’

Error Over Full Serial Ports. Software ConfigurableTemperature Range. Bipolar or Unipolar Operation.

Half Duplex Serial I/O.LTC1296C,I,M 12-Bit, Serial I/O, 12 Bits ±0.5LSB Linearity, 46ksps 5V 12mA, J, N 12-Bit ADC with Built-In 8-Channel

A/D Converter System with ±3LSB Offset, and or 10µA MUX and Sample-and-Hold.8-Channel Multiplexer. ±0.5LSB Full-Scale ±5V During Compatible with All Microprocessors’

Error Over Full Shutdown Serial Ports. Software ConfigurableTemperature Range. Bipolar or Unipolar Operation.

Programmable Power-Down Includes aSystem Shutdown Output.

LTC1297C,I,M 12-Bit, 20µs, 5V, Sampling 12 Bits ±0.5LSB Linearity, 20ksps 5V 12mA, J, N 12-Bit ADC with Built-In Sample-and-A/D Converter with Differential ±3LSB Offset, and 10µA Hold. Compatible with All Micro-Input and Serial Output. ±1LSB Full-Scale During processors Serial Ports. AutomaticInput Range with 5V Supply: Error Over Full Shutdown Power-Down.0V ≤ VIN ≤ 5V. Temperature Range.

LTC1298C,I 12-Bit, 8-Pin, Serial I/O, 12 Bits ±2LSB Linearity, 11.1ksps 5V 640µA, N, S 12-Bit ADC with Built-In Sample-and-340µA (Typ) Sampling A/D ±0.75LSB Differential to 3µA Hold and 2-Channel MUX. CompatibleConverter with Automatic Nonlinearity, 9V During with All Microprocessors Serial Ports.Power-Down. ±3LSB Offset, and Shutdown Automatic Power-Down.

±8LSB Full-ScaleError Over Full

Temperature Range.

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

Application Note 62

AN62-28

TOTAL MAXIMUMPART RESOLU- UNADJUSTED SETTLING VOLTAGE SUPPLY PKGS. IMPORTANT

NUMBER DESCRIPTION TION ERROR TIME SUPPLY CURRENT AVAIL. FEATURES

LTC1257C,I 12-Bit, Serial I/O, 8-Pin 12 Bits ±0.5LSB DNL, 6µs 5V 600µA N, S 12-Bit DAC with Cascadable Serial I/O,D/A Converter. Cascadable ±3.5LSB INL (±1/2LSB) to at Built-In Reference, and Voltage Output.Serial I/O. Internal 2.048V 15.5V VCC = 5V Wide Supply Range of 5V to 15.5V.Reference. Voltage Output. Space Saving SO-8 Package.

LINEAR TECHNOLOGY CORPORATION 1994

LT/GP 1094 10K • PRINTED IN USA

Digital-to-Analog Converter Selection Guide

T.C. *LT1034B-1.2 *LT1034-1.2 *LT1004-1.2 *LM385B-1.2 *LM385-1.2

ACCURACY *LT1004-1.2 *LT1034B-1.2 *LT1034-1.2 *LM385B-1.2 *LM385-1.2

VOLTAGE REFERENCES Listed by Temperature Drift (T.C.) and Initial Accuracy

1.25V OUTPUT

T.C. LT1019C-4.5

ACCURACY LT1019C-4.5

T.C. LTZ1000 LM399A LM399 LM329A LM329B LM329C

ACCURACY LM329A LTZ1000 LM329B LM329C LM329D LM399A

T.C. LT1021C-10 LT1031C LT581K LT1019-10 LT1031D LT581J REF-01E LT1021B-10 LT1021D-10 LT1031B REF-01H REF-01C

ACCURACY LT1021B-10 LT1031B-10 REF-01E LT1031C LT581K LT1019-10 LT1021C-10 LT1021D-10 LT1031D REF-01H LT581J REF-01C

T.C. LT1027C-5 LT1027D-5 LT1027E-5 LT1021C-5 LT1019-5 LT1029A REF-02E REF-02H LT1021B-5 LT1021D-5 LT1029 REF-02C REF-02D

ACCURACY LT1027C-5 LT1021B-5 LT1027D-5 LT1027E-5 REF-02E LT1019-5 LT1021C-5 LT1021D-5 LT1029A REF-02H LT1029 REF-02C REF-02D

T.C. LT1019C-2.5 LT1009C-2.5 LT580M LT1034B-2.5 LT580L *LT1004C-2.5 LT1034-2.5 LT580K *LM385B-2.5 LM336B-2.5 *LM385-2.5 LM336-2.5

ACCURACY LT580M LT1019C-2.5 LT1009-2.5 LT580L LT1034-2.5 LT580K *LT1004C-2.5 *LM385B-2.5 *LM385-2.5 LT580J LM336B-2.5 LM336-2.6

T.C. LT1021B-7 LT1021D-7 LT1034

ACCURACY LT1021B-7 LT1021D-7 LT1034

7V OUTPUT4.5V OUTPUT

AN62 BF01*Micropower

6.9V TO 6.95V OUTPUT

10V OUTPUT

5V OUTPUT

2.5V OUTPUT

APPENDIX B

Linear Technology Corporation1630 McCarthy Blvd., Milpitas, CA 95035-7487(408) 432-1900 FAX: (408) 434-0507 TELEX: 499-3977

Documents

AN62 - Data Acquisition Circuit Collectioncds.linear.com/docs/en/application-note/an62.pdfAN62-1 Application Note 62 October 1994 Data Acquisition Circuit Collection Kevin R. Hoskins