# Manufacturing considerations

## Crystal trimming

For the DA1469x based devices with WiRa functionality enabled is it critically important to have the crystal 32MHz trimmed within 3 ppm.

## Antenna

### Radiation pattern

Antenna radiation pattern as a significant impact on the WiRa performance. It is highly important
to select an antenna with a balanced radiation pattern. It is possible to implement a suitable antenna as a chip ceramic and PCB trace antenna.

### Offset trimming

The board design will dictate the delay from the antenna to the antenna demodulator. This infers a static offset in the distance measurement. The
software can compensate for it and there's a parameter store in the configuration
partition of the flash to set it correctly. The board needs to be characterized in
order to allow the correct offset to be program in production.

## Battery

The battery profile needs to be correctly setup in the `custom_charging_profile.h` file to allow the charge current to be correctly.

## Device parameters

Please refer to the [Device parameters](additional_features.html#configuration-parameters) in order to setup correctly the non-volatile 
parameters during production.