About
The Battery Shield powers your OpenMV Cam from a 1.8V to 5.5V source connected using a standard 2.1mm DC barrel jack. This is perfect for powering your OpenMV Cam from three alkaline batteries in series using a standard battery holder with a 2.1mm DC plug. Two alkaline batteries in series also work, although the full capacity of both batteries cannot be used completely before the battery shield shuts down.
You may attempt to use four alkaline batteries in series; however, the fully charged voltage of four alkaline batteries in series may slightly exceed the onboard buck/boost converter's maximum allowed voltage. Proceed with caution.
The shield also features a wide voltage range 6-36V input, which is robust to reverse voltage and features robust transient surge protection. Use this input to power your OpenMV Cam from 12/24V power supplies without having to worry about damaging your camera. The wide range voltage supply outputs 5.6V on VIN via an ideal OR'ing diode so that you can power your OpenMV Cam from multiple shields with OR'ing diodes (e.g. all of our dual header column shields). This input can be used at the same time as the 1.8V to 5.5V input.
The shield also features a robust 0-6V ADC input (AIN) connected to the 1.8V to 5.5V DC barrel jack, which outputs 0-2.8V to your OpenMV Cam on P6 for measuring the attached battery voltage. The input is robust to reverse voltage. If you don't need the ADC input, you can disconnect it from P6, too.
This shield is compatible with all OpenMV Cam models.
Note that the 1.8V to 5.5V input directly powers your OpenMV Cam via its RAW pin, which bypasses the onboard battery charger. The battery shield is designed to draw microamps of current in operation, allowing you to deploy an OpenMV Cam to run for years on alkaline batteries while your OpenMV Cam is in deep sleep (e.g. see the OpenMV Cam RT1062, which draws ~30uA in deep sleep).
Applications
This shield is perfect for customers who need to power their OpenMV Cam from intrinsically safe voltage sources (e.g., not LiPos, which may explode/catch fire).
Why make the battery shield? We were asked to! The battery shield has found a home powering OpenMV Cams from batteries for years, deployed in industrial facilities!
Specs
- PWR (6V-36V) - Reverse Voltage Tolerant (up to -36V) - provides VIN with 5.6V - up to 600mA Draw
- BAT (1.8V-5.5V) - Reverse Voltage Tolerant (up to -5.5V) - provides RAW with 3.5V - up to 800mA Draw
- All external interfaces have robust transient voltage protection
The external pin header is designed to grab 20-24 gauge solid core wire and not fail due to vibration. Once you hook up a circuit using this shield, you can be sure it will not come apart. Please use a flat head 1.0-2.0mm screwdriver to release the spring lock headers if you need to remove a wire.
If you want to use this shield with the stranded wire, we recommend using 22-24 gauge ferrules (here) crimped (here) to your wires before inserting them into the shield.
Power Consumption
- < 1µa @ 3.3V from your OpenMV Cam's 3.3V rail
- ~8µa from the DC battery source
