ATmega128RFA1
description
Transcript of ATmega128RFA1
![Page 1: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/1.jpg)
ATmega128RFA1
Power Measurement
![Page 2: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/2.jpg)
ATmega128RFA1
• SoC (uC and Transceiver)• Up to 16 MHz (i.e. almost 16 MIPS)• Voltage range: 1.8v to 3.6v• 16K bytes RAM• 128 K Flash• Zigbee compliant transceiver
![Page 3: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/3.jpg)
ATmega128RFA1
• Transceiver– TX Power up to 3.5 dBm (2.24 mW)– Speed -> 250 kb/s and 500 kb/s, 1 Mb/s, 2 Mb/s– Security -> AES (128 bits)– RX current -> 12.5 mA – TX current -> 14.5 mA (max output power)
![Page 4: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/4.jpg)
Power Control Features
• Power Reduction Registers– PRR0 (TWI, Timers, etc)– PRR1 (one bit to shutdown transceiver)– PRR2 (for disabling the four SRAM blocks)
• Watchdog Timer
• Brown-Out detect (BOD)
![Page 5: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/5.jpg)
Important Peripherals
• Timers• ADC• TWI (I2C) -> RTC wake up• WDT (wakeup or reliability enhancement)• Transceiver
![Page 6: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/6.jpg)
Sleep Current
• Power down mode (deep sleep)• All peripherals disabled– PRR0 = 0xFF– PRR1 = 0xFF
• WDT enabled
Current = 800 nA
![Page 7: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/7.jpg)
Sense & Send: Cycle Time
3.44 ms
![Page 8: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/8.jpg)
Sense & Send: TX Time
1.68 ms
![Page 9: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/9.jpg)
Sense & Send: Sense Current
4.2 mA
![Page 10: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/10.jpg)
Sense & Send: TX Current
15.6 mA
![Page 11: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/11.jpg)
Life Time Estimate
• Ampere Hour– Sense -> 2.05 x 10-6 mAH– Tx -> 7.28 x 10-6 mAH– Total (sense & send) -> 9.33 x 10-6 mAH
• In ‘one hour’– # of Tx -> 450– Sense & Send -> 4.1985 x 10-3 mAH– Sleep -> 2.88 x 10-6 mAH– Total (sense, send & sleep) -> 4.2 x 10-3 mAH
![Page 12: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/12.jpg)
Life Time Estimate
• For a battery of 200 mAH
– # of hours we get is
200/4.2 x 10-3
i.e. 47619 hrs
or about 5 years
![Page 13: ATmega128RFA1](https://reader036.fdocuments.in/reader036/viewer/2022062310/5681640d550346895dd5b3e7/html5/thumbnails/13.jpg)
Additional Possible Optimization
• Frequency scaling– Static– Dynamic
• Use of Real-Time Clock– Keep watchdog timer disabled in sleep mode
• RTC chip takes less current than the WDT– Wake up on RTC alarm interrupt
• More flexible (not just max of 8 sec)