...
| Module | 3.3V Rail Max Required Current (mAhmA) | 5V Rail Max Required Current (mAhmA) | 7.2V Battery Max Required Current (mAhmA) |
|---|---|---|---|
| Backplane | 0 | 0 | 60 |
| Power | 0 | 0 | 945 (from calculation below) |
| Autopilot | 0 | 500 | 1000 |
| Radio | 565 | 0 | 0 |
| Sensor | 400 | 100 | 0 |
| Total | 965 | 600 | 2005 |
...
Assume 90% step down efficiency
Power = (965mAh 965mA * 3.3V + 600mAh 600mA * 5V) * 1.1 = 6,803mWh803mW
Amp-hours Amperage = 6,803mWh 803mW / 7.2V = 945mAh 945mA
2022 Backplane & Future-proofing
| Module | 3.3V Rail Max Required Current (mAhmA) | 5V Rail Max Required Current (mAhmA) | 7.2V Battery Max Required Current (mAhmA) |
|---|---|---|---|
| Backplane | 0 | 0 | 60 |
| Power | 0 | 0 | 2212 (from calculation below) |
| Autopilot | 0 | 500 | 1000 |
| Radio | 565 | 0 | 0 |
| Sensor | 400 | 100 | 0 |
| Future Board(s) Allotment | 1000 | 1000 | 1000 |
| Total | 1965 | 1600 | 4272 |
...
Assume 90% step down efficiency
Power = (1965mAh 1965mA * 3.3V + 1600mAh 1600mA * 5V) * 1.1 = 15,933mWh933mW
Amp-hours = 15,933mWh 933mW / 7.2V = 2,212mAh212mA
Takeaways
- Battery shall be able to handle 4,272mAh 272mA transient power draw @ 7.2V
- Battery shall be able to handle 3,272mAh 272mA continuous power draw @7.2V
- 5V circuitry shall be able to supply 1600mAh1600mA
- 3.3V circuitry shall be able to supply 1965mAh1965mA
- All traces shall be rated for their appropriate current requirements
- 3.3V → 1965mAh 1965mA max
- 5V → 1600mAh 1600mA max
- 7.2V → 4272mAh 4272mA max