Hi
- I have custom board with nrf52832. I have lion batery and 3.3V ldo for powering device. I attached shematic.
- For preventing lion battery decreasing below 3V, i used a 3.1V voltage detector ic. This detector (STM1061N31WX6F) makes LDO enable pin logic low so everything stops. Here i have 1Mohm pullup resisor.
- Detector ic disable ldo 3.1V and re eanble 3.3V. If i load bottloader code detector ic still working same but nrf52832 hangs. Everything is fine without adding bootloader code.
- I dont have problem loading apk over mobile with dfu, its ok.
- I have 50 circuits for preproduction. I have 50 product.
- When i load softdevice and load "bootloader_secure_ble". I can see DFU_Targ with mobile but when i click no service appear.
- When i rise batery voltage starts working, I can see services. But this happen with different batery voltages with different products. One 4V, another 3.8V, another 4.3V. But start to see 3.3V ldo output with battery voltage 3.3V.
- I short pullup resistor of LDO enable, load apk over mobile device and leave shorting pullup (1Mohms), device hangs. Nothing advertise.
- My apk is modified "ble_app_uart ". I add pwm, adc, low power mode and some other things. They all fine.
Its something very strange but i cant find what differs with starting device with "ble_app_uart " or with "bootloader_secure_ble".
Is there any difference for Power on Reset of DC DC conveter or do you have any idea.
Thanks
Ferhat
