1

S. Dhawan, O. Baker, H. Chen, R. Khanna, J. Kierstead, F. Lanni, D. Lynn, A. Mincer,

C. Musso S. Rescia, H. Smith, P. Tipton, M. Weber

Progress on DC-DC converters for SiTracker for SLHC

Yale University, New Haven, CT USABrookhaven National Laboratory, Upton, NY USA

Rutherford Appleton Laboratory, Chilton, Didcot, UKNational Semiconductor Corp, Richardson, TX, USA

New York University, New York, NY, USA

2

4088 Cables10 Chip Hybrid – SCT

Module for LHC

Counting House

3.5 V

20 Chip Hybrid – Si TrModule for Hi Luminosity

Cable Resistance = 4.5 Ohms

1.5 amps

2.4 amps

X 10 DC-DCPower

Converter

20 Chip Hybrid – Si TrModule for Hi Luminosity

1.3 V

1.3 V

2.4 amps

10.25 V

12.1V

14.08 V13 V

Power Delivery with Existing SCT Cables (total = 4088)Resistance = 4. 5 Ohms

0

10

20

30

40

50

60

70

80

90

100

3.5 V @ 1.5 amps 1.3 V @ 2.4 amps 1.3 V @ 2.4 ampswith x10 Buck

switcher. Efficiency90%

Voltage @ Load

Po

we

r E

ffic

ien

cy %

Efficiency

Voltage Drop = 6.75 V

Voltage Drop = 10.8V

0.24 ampsVoltage Drop = 1.08 V

Length of Power Cables = 140 Meters

3

Agenda

Learning from Commercial Devices Buck > Voltage, EMI Plug In Cards for ABCN2.5 Hybrids - Noise Tests @Liverpool

Require Radiation resistance & High Voltage operation Thin Oxide High Voltage with Thin Oxide ? DMOS, Drain Extension 12V @ 5 nm , 20V @ 7 nm

HEMT has no Oxide – Higher Voltage ? 200 Mrads 20V

4

Buck Regulator Efficiency after 100 Mrad dosage

40

45

50

55

60

65

70

75

80

0 1 2 3 4 5 6

Output Current Amps

Po

wer

Eff

icie

ncy

%

AfterExposure

BeforeExposure

Enpirion EN5360 Found out at Power Technology conference 0.25 µm Lithography Irradiated Stopped on St. Valentines Day 2007 No effects after 100 Mrads Noise tests at Yale, RAL & BNL. 20 µm Al is good shield for Air Coils All other devices failed, even other part numbers from Enpirion We reported @ TWEPP 2008 - IHP was foundry for EN5360 What makes Radiation Hardness ? Chinese Company Devices

5

ControllerLow Voltage

Power Stage Drivers

V reference

Pulse Width Controller

Buck Safety

Synchronous Buck Converter

Power Stage-High Volts

Control Switch 30 mΩ

Synch Switch20 mΩ

Control Switch: Switching Loss > I2

Synch Switch: Rds Loss Significant

Error Amp

100 ns

Synch

Control

900 ns

Control

Synch

Minimum Switch ON TimeLimits Max Frequency

500 ns 500 ns

Vout = 10%

Vout = 50%

80.5

78.4

75.2

Input Voltage (8-14 V)

Eff

icie

nc

y (

%)

6

Control Switch

EMI Antenna Loops

Current is switched from Q1 to Q2 with minimum Impedance change

Since the switching noise is generated primarily by the power stage of the supply, careful layout of the power components should take place before the small signal components are placed and routed. The basic strategy is to minimize the area of the loops created by the power components and their associated traces. In the synchronous buck converter shown above the input (source) loop #1 ideally consists of a DC current with a negligible AC ripple. Loop numbers 2 and 3 are the power switch loops. The current in these loops is composed of trapezoidal pulses with large peaks and fast edges (di/dt and dv/dt). The area of these loops will be determined primarily by how close together the power components, the inductor, and the capacitors Cin and Cout can be placed. The closer the components, the shorter the PCB traces connecting them, and therefore the smaller loop area.

Q2

Q1

Advice form a company application note

7

Load0.25 µm Technology Test ASIC 2.5 V @ ~ 3 amps. Actual 5 amps 0.13 µm Technology ASIC 1.3 V @ ?

Vin = 2.5 – 17 VVout = 2.5 / 1.3 V

Enable

Plug in Card – Power Yale Model 2151

GND

GND

Power Good

RequirementsVoltage Ratio > 8For Good Efficiency Iout >3 ampsAir Coil / MagneticsRadiation Hardness

Small Plug-in Card

Output VoltageTolerance +/- 5%

Absolute Max 10%For Long Lifetime

8

4 layersLayer1: Top Coil with no connection - ShieldLayer2: coil Connect in seriesLayer3: coil Connect in seriesLayer4: Bottom Coil with no connection- Shield

Spacing between Layer 2 & 3 = 14 mills ( 0.35 MM) Proximity EffectTop & Bottom can be more as there is no loss from these

Spiral Coils Resistance in mΩ

Top Bottom

3 Oz 57 46

10 mil Cu 19.4 17

Coupled InductorConnected in Series

Shielded Buck Inductor

Shielding Spiral – One end to GND

Shielding Spiral – One end to GND

9Yale University April 09, 2009 Model 2151_Max8654Yale University April 09, 2009

Power Out

Power INEnable / DisablePower Good Out

Kelvin points for Vin & Vout

10

MAX8654 with embedded coils (#12), external coils (#17) or Renco Solenoid (#2) Vout=2.5 V

0

10

20

30

40

50

60

70

80

90

100

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5Output current (amps)

Eff

icie

ncy (

%)

MAX #12, Vin = 11.9 V MAX #17, Vin = 11.8 V MAX #2, Vin = 12.0 V

PCB embedded Coil

Copper Coils

Solenoid

11Yale Model 2151a

Plug In Card: DC-DC Powering 2 Different ICs 3 Different Coils

Monolithic: 14V, 8A, 1.2MHzMultichip: 16V, 8A, 1.5MHz

Embedded 3 oz Cu Etched Cu Foils 0.25 mmSolenoid without Ferrite

Coil Board # Common Power Input Noise

Mode Choke To Dc_DC Electrons rms

Solenoid Max # 2 No 881

" " " 885

Copper Coil IR # 17 No Switching 666

" " Yes " 634

" " Yes Linear 664

Embedded Max 12 No Linear 686

" " Yes " 641

All Channels

Trimmed

" " Yes " 648

12

Sensor 1 cm from Coil

Shield 20 µm Al Foil Noise NO change with Plug in cardon top

Noise Same with Linear or DC - DC

13

Controller : Low Voltage

High Voltage: Switches –

LDMOS, Drain Extension, Deep Diffusion etc

>> 20 Volts HEMT GaN on Silicon, Silicon Carbide, Sapphire

Can We HaveHigh Radiation Tolerance & Higher Voltage Together ???

14

Thin Gate Oxide

Book ‘Ionizing Radiation Effects in MOS Oxides’ Author Timothy R. Oldham

Thin oxide implies lower operating voltage

15

High performance RF LDMOS transistors with 5 nm gate oxide in a 0.25 μm SiGe:C BiCMOS technology: IHP MicroelectronicsElectron Devices Meeting, 2001. IEDM Technical Digest. International2-5 Dec. 2001 Page(s):40.4.1 - 40.4.4

LDMOS StructureLaterally DiffusedDrain Extension

High Voltage / high FrequencyMain market. Cellular base stations

16

R. Sorge et al , IHP Proceedings of SIRF 2008 ConferenceHigh Voltage Complementary Epi Free LDMOS Module with 70 VPLDMOS for a 0.25 μm SiGe:C BiCMOS Platform

17

IBM Foundry Oxide Thickness

Lithography Process Operating Oxide

Name Voltage Thickness

nm

0.25 µm 6SF 2.5 5

3.3 7

0.13 µm 8RF 1.2 & 1.5 2.2

2.2 & 3.3 5.2

18

Company Device Process Foundry Oxide Time in Dose before Observation

Name/ Number Name Thickness Seconds Damage seen Damage Mode

Country nm

IHP ASIC custom SG25V GOD IHP, Germany 5 53 Mrad slight damage

XySemi FET 2 amps HVMOS20080720 China 7 52 Mrad minimal damage

XySemi XP2201 HVMOS20080720 China 7 In Development

XySemi XPxxxxHVMOS20080720 China 7

In Development Synch Buck

XySemi

XP5062

China

12.3

800

44 krad

loss of Vout regulation

TITPS54620 LBC5 0.35 µm 20 420 23 krad abrupt failure

IR IR3841 9 & 25 230 13 Krads loss of Vout regulation

Enpirion EN5365 CMOS 0.25 µm Dongbu HiTek, Korea 5 11,500 85 krad

Increasing Input Current,

Enpirion EN5382 CMOS 0.25 µm Dongbu HiTek, Korea 5 2000 111 Krads loss of Vout regulation

Enpirion EN5360 #2 SG25V (IHP) IHP, Germany 5 22 Days 100 Mrads Minimal Damage

Enpirion EN5360 #3 SG25V (IHP) IHP, Germany 5 10 Days 48 Mrads Minimal Damage

Non IBM Foundry ICs

19

For Higher Radiation Resistance Oxide Thickness is predominant Effect Others Epi Free processing is Good ? Oxide Processing is standard ?????

20

From China

21

XY Semi (VD = 12V)2 Amp FET- HVMOS20080720 Process

00.020.040.060.08

0.10.12

0 0.5 1 1.5

Vg (Volts)

Id (A

mps

)I

0 rad

1 Mrad

5.4 Mrad

33 Mrad

52 Mrad

IHP PMOS TransistorVG versus ID at selected Gamma Doses

0

0.2

0.4

0.6

0.8

1

0 0.5 1 1.5 2 2.5VG (Volts)

I D (m

A)

Pre-Irradiation

13 Mrad

22 Mrad

35 Mrad

53 Mrad

IHP NMOS Transistor

VG versus ID at Selected Gamma Doses

0

0.5

1

1.5

2

2.5

0 0.5 1 1.5 2 2.5

VG (Volts)

I D (

mA

)

Pre-irradiation

13 Mrad

22 Mrad

35 Mrad

22

Depletion ModeNormally ON

Enhancement ModeNormally OFF

23

GaN for Power Switching

24

RF GaN 20 Volts & 0.1 amp 8 pieces: Nitronex NPT 25015: GaN on Silicon Done Gamma, Proton & Neutrons 65 volts Oct 2009

2 pieces: CREE CGH40010F: GaN on siC

6 pieces: Eudyna EGNB010MK: GaN on siC Done Neutrons Switch GaN International Rectifier GaN on Silicon Under NDA

Gamma: @ BNLProtons: @ LansceNeutrons: @ U of Mass Lowell

Gallium Nitride Devices under Tests

Plan to Expose same device toGamma, Protons & Neutrons

25

Nitronex 25015 Serial # 1

0

0.02

0.04

0.06

0.08

0.1

0.12

-2.5 -2.3 -2.1 -1.9 -1.7 -1.5 -1.3 VGS Volts

ID A

mps 4.2 Mrad

0 rad

17.4 Mrad

26

Source

HEMTPulse

Generator0.1 – 2 MHz

50 % Duty Cycle

July 28. 2009 FET Setup for Proton Radiation Exposure @ LANSCE

.

~ 0.070 AmpsPower SupplyV out = 20

Drain

Gate

100

0 to -5 V

Powered FET

DMMDC mV

330 2 Watts 1 Ω

GND

50 ΩTerminator 2 Shorted

FETs

G

DS

Pomona Box

Reading = ~ 0.035 Amps@ 50% Duty Cycle

No change in the average current for 200 Mega rads

30 meter Coax

27

IR’s basic current GaN-on-Si based device structure is a high electron mobility transistor (HEMT), based on the presence of a two dimensional electron gas (2DEG) spontaneously formed by the intimacy of a thin layer of AlGaN on a high quality GaN surface as shown in Figure 1. It is obvious that the native nature of this device structure is a HFET with a high electron mobility channel and conducts in the absence of applied voltage (normally on). Several techniques have been developed to provide a built-in modification of the 2DEG under the gated region that permits normally off behavior.

Aside from providing high quality, reliable and a low-cost CMOS compatible device manufacturing process, the GaNpowIR technology platform also delivers dramatic improvements in three basic figures of merit (FOMs), namely specific on-resistance RDS(on), RDS(on)*Qg and efficiency*density/cost.

28Intel won’t disclose any details till product is announced

29

ConclusionsLearned from commercial Devices, Companies & Power conferences Can get high Radiation Tolerance & Higher VoltageHigh Frequency > Smaller Air coil > Less Material Goal: ~20 MHz Buck, MEM on Chip size 9 mm x 9mmPower SOC: MEMs Air Core Inductor on Chip Study Feasibility 48 / 300V Converters Irradiation: Run @ Max operating V & I.

Limit Power Dissipation by Switching duty cycleOnline Monitoring during irradiation for faster resultsYale Plug Cards can be loaned for EvaluationCollaborators are Welcome

30The End Neither it on Top of the World

Working on Power Supply Is not Glamorous