UC Berkeley
DAC Student Design CompetitionDAC Student Design Competition
Shaker
15mahNiMH
< 200mvbias
1.0 - 1.4v
2.0 – 2.8v
chargepump
radio PA power enable
analog switch
0.65v
1.0vRadio digital power(GPIO pin)
MSP430uC
SPI serial IF
Wakeup
JTAG external IF
TPMSSensor
powerswitches
SPI VDD
Tx VDD
SPI serial IF
Tx datalevel
shifters
Interface
radio
RF
SPI pwr on/off
PA pwr on/off
SPI serial IF
Tx data
Sensor/Digital
shunt reg.
linearregulator
“Picocube: A 1cm3 Sensor Node Powered by Harvested Energy”Yuen-Hui Chee, Mike Koplow, Michael Mark, Nathan Pletcher, Mike Seeman, Fred Burghardt,
Dan Steingart, Jan Rabaey, Paul Wright, Seth Sanders
UC Berkeley
Cube AnatomyCube Anatomy
• Stacked PCBs
• 1cm square
uC boardtop/bottom
sensor board #1top/bottom
ona
dime
radio boardtop/bottom
switch/power boardtop/bottom
storage boardtop/blank bottomsensor board #2
top/bottom
radio COB die
UC Berkeley
Custom TechnologyCustom Technology
• Custom PicoCube Transmitter w/ FBAR– 10 kbps, 10 m range at 0
dBm– Supports FSK modulation,
but useful for OOK– Custom 200Ω antenna,
matching PA
• Power Management IC– 2 switched-capacitor
converters (0.7V, 2.1V)• 84% efficient
– Synchronous Rectifier• 88% efficient from shaker
– Ultra-low-power references and other circuitry