Power¶
v2 takes a single 5 V input on J5 pin 1 and generates the sensor rails
on-board. You never supply sensor voltages yourself.
5 V only
There is no wide-input regulator. J5 pin 1 feeds a 3.3 V LDO directly
through a series Schottky diode. Wiring a flight battery to it will destroy
the board.
Input¶
| Parameter | Value |
|---|---|
| Input voltage | 5 V nominal |
| Maximum | ~5.5 V — see the limit below |
| Connector | J5 pin 1 (JST GH 1.25 mm, 4-pin) — which pin, in a photo |
| Ranging current | Profile and load dependent; measure at the regulated 5 V input |
| Peak current | brief inrush at power-on as all eight sensors initialise |
| Protection | reverse polarity only (D2, SS14 Schottky in series) |
Where the limit comes from¶
The supply chain is short and has no headroom above 5 V:
U3 is a TLV75733 3.3 V LDO whose input is rated 5.5 V recommended,
6 V absolute maximum. Nothing upstream of it clamps or regulates — D2 is a
plain series diode that only blocks reverse polarity and drops roughly 0.3–0.4 V.
So the LDO sees very nearly whatever you apply to J5 pin 1.
U1 (TPS62130) is a wide-input buck, but it is not the input stage: it runs
from the 3.3 V rail to produce the sensors' 1.8 V. It does not protect the input.
There is no overvoltage protection
D2 blocks reverse polarity and nothing else — any positive voltage passes
straight through to a 6 V-max part. This is a known limitation of the current
revision and is on the list for the next one. Until then, feed J5 from a
regulated 5 V rail, and check with a meter before plugging in an unfamiliar
supply.
Powering it¶
| Situation | How |
|---|---|
| Bench | A USB-UART adapter's 5 V/VCC pin into J5 pin 1, with its TX/RX/GND on pins 2/3/4. One cable does power and data. |
| On a vehicle | A regulated 5 V rail from the flight-control unit or power module into J5 pin 1. |
Because J5 carries power and UART on the same connector, a single 4-wire lead
is all the integration needs. See Bring-up & Setup.
What the board provides¶
- Both sensor supplies (+3V3 and +1V8) are generated on-board and distributed through the eight sensor connectors.
J6pin 6 is +3V3. It is there so a debug probe can sense target voltage — do not use it to power the board.
Choosing a ranging profile¶
The 10 Hz / 10 ms candidate collects more light per measurement than the earlier 15 Hz / 5 ms experiment, at a longer frame interval. An 8×8 frame uses four sub-integrations:
| Profile | Exposure per frame | Calculated exposure duty |
|---|---|---|
| 15 Hz / 5 ms | 20 ms | 30% |
| 10 Hz / 10 ms candidate | 40 ms | 40% |
| 15 Hz / 10 ms | 40 ms | 60% |
Exposure duty is not total board power. Sensor processing, MCU activity, the UART stream, and losses in the input diode and 3.3 V LDO also contribute. Keep voltage, connected peripherals, and scene fixed when comparing input current/watts. Check reliable detections at known distances indoors and in daylight; dashboard frame rate alone does not establish range or accuracy.
The candidate's power and range have not yet been measured. Shortening integration can save power but makes weak reflections harder to detect. ST integration timing.