51822 Consuming More power than 51422

[Harsha]

HI, I am facing some serious issue in 51822. It consumes more power than 51422 on a same custom board. I am using same software for both with s130. Surprisingly the 51422 consumes 1.15 mA in system power off whereas the 51822 consumes just 2uA in power off in same circuit. I have no clue on whats happening,

Kindly help. I am using external lf crystal as clock source.

I wonder if with the same circuit (custom board) and with the same firmware, NRF51422 will consume more power (at least 10 times) than NRF51822. Please clarify.

[Leon Woestenberg]

One or two years ago I noticed that our devices had to be power-cycled after programming with Segger, otherwise they drew a lot of power (and drained three parallel CR2032 batteries in about 30 days. - these where beacons)

I think this had to do with the JTAG component in the nRF still drawing power after programming its internal FlashROM.

You could at least verify this and report back here.

[Harsha]

I don't think thats an issue in this case. The same custom board works fine with 51822.

[MartinBL]

When we see a mysterious increase in current of ~1mA the first suspect is the issue that Leon mentions. After programming the chip stays in debug mode and needs a power cycle to exit it. I agree with you that it is unlikely since it works on a 51822, but it is worth to investigate before ruling it out.

I can't think of any reason why nRF51822 should draw more power than nRF51422 so could it be a hardware issue? A short circuit on your PCB maybe? A bad solder joint? Have you tried both chips on the same board?

By the way, in your original post you write both that nrf51822 draws more power than nr51422 and vice versa. Which is it?

[Harsha]

Hi Martin, In the original post that was a typo. So I changed it. Can you tell me how to bring the chip out of debug mode?. I tried all possible ways. Also I dont think there is a hardware issue. I have around 40 pcbs. All pcbs consumes same power with 51422. Expecting your reply.

[MartinBL]

I have never heard of problems like this. This case sound similar and turned out being a hardware issue. What chip revisions do you have? What does the markings on the chips say?

Can you create a support request on mypage and upload your code and schematics?