Battery #
- Voltage: 3.6V
- Chemistry: NiMH
- Cells: 3
- Size: AA
NTC (Thermistor) white cable #
- 22°C - 10kOhm
- 35°C - 6kOhm
- 5°C - 30kOhm
- MF58 10kOhm 3950K (Confirmed by Boxine)
Plug #
- JST PH 2mm 3pin
Cable Length for custom battery packs #
- Black: 17cm
- Red: 15cm
- White: 15cm
ADC Voltage Map #
| Box ID | User | voltage in V | ADC raw | charging | original battery | notes |
|---|---|---|---|---|---|---|
| B-Dev Blue | SciLor | 3.975 | 2701 | 0 | 1 | |
| B-Dev Blue | SciLor | 4.16 | 2824 | 0 | 1 | |
| B-Dev Blue | SciLor | 4.25 | 2882 | 0 | 1 | Max |
| B-Dev Blue | SciLor | 4.39 | 3188 | 1 | 1 | |
| B-Dev Blue | SciLor | 4.44 | 3195 | 1 | 1 | Max |
| Lila | SciLor | 3.686 | 2489 | 0 | 0 | |
| Lila | SciLor | 3.659 | 2478 | 0 | 0 | Shut Off Message |
| Lila | SciLor | 4.26 | 2870 | 0 | 0 | Max |
| Lila | SciLor | 4.47 | 3180 | 1 | 0 | Max |
| Red | SciLor | 3.641 | 2456 | 0 | 0 | |
| Red | SciLor | 3.540 | 2400 | 0 | 0 | Shut Off Message |
Voltage measurement TP38
from machine import Pin
from machine import ADC
p_charger = Pin('GP17', mode=Pin.IN)
p_charger.value()
adc = ADC()
p_battery = adc.channel(pin='GP5')
p_battery.value()
Voltage calculation #
From the data above following calculation can be used:
voltage = adc * 100/67690; //charger disconnected
voltage = adc * 100/71907; //charger connected
The OFW uses a slightly different formula:
voltage = ((adc * (40000/26173)) - 89) / 1000
adc = ((1000 * voltage) + 89) * (26173/40000)
The OFW uses the value 3,601v or adc=2297 as low battery voltage (0xE11). As shutoff voltage 3,299v / 3,300v or adc=2099/2100 are used (0xCE3/0xCE4).
Photos (Custom Battery Pack) #
Power supply #
- Voltage: 9V
- Current: 1.5A
- Plug 5.5x2.1mm (+9V inner side)
Photo #
