AXP209 shutting down

[abhilashkgopinath]

Dear Experts,
    We designed based on A20 processor with AXP209. Now we are facing a problem related to power. We are using only ACin for powering.

When we power on with 5V to ACIN, we are getting 3V,1.3V, 2.8V, 1.2V & other voltages only for 100ms. After that all the voltages goes down to 0V except 1.3V LDO and we are getting VINT as 2.5 V and 1.2V on Bias pin.

Pressing the N_OE switch shows a small blip for same 100ms. We have done prototype for 5 NOS, all the boards are behaving same.

Any suggestions are welcome.

Regards,
Abhilash K Gopinath

[vijayboboe]

We are also facing the same problem. Any suggestions ?

[lase]

Hi, I had the same problem.

The reason was that I didn't use LDO2, LDO3, LDO4 so I didn't connect anything to LDO24IN and LDO3IN (these are all three enabled by default). After connecting these to IPSOUT it started working for me. I think AXP209 monitors the output of those LDOs and shuts down when it notices its voltage is not as configured.

Hope this helps someone!