topic Re: PSWITCH left unconnected and DCDC issue in i.MX Processors

PSWITCH left unconnected and DCDC issue

dgotfroi — Mon, 28 Apr 2014 11:33:14 GMT

Hello all,

I use a IMX28 with an external +5V power supply. I don't have any battery connected.

So, can I leave PSWITCH unconnected or do I have to tie it to GND or other ?

Second question, since I don't use a battery, do I need to connect something to "Battery", "DCDC_BATT" and "VDD4P2" ?

I followed the schematic of the evaluation board and my shematic looks like that :

But "VBAT" is leave unconnected, so can I remove C1 to C10, R1 to R4, D1 and L1 ?

Many thanks

Re: PSWITCH left unconnected and DCDC issue

victorien — Mon, 28 Apr 2014 13:04:29 GMT

You can find the best way to supply your board on this document http://cache.freescale.com/files/32bit/doc/app_note/AN4199.pdf?fasp=1&WT_TYPE=Application%20Notes&WT_VENDOR=FREESCALE&WT… chapter 4

Re: PSWITCH left unconnected and DCDC issue

dgotfroi — Mon, 28 Apr 2014 13:17:55 GMT

Many thanks for this very useful answer.

And what about PSWITCH ?

Re: PSWITCH left unconnected and DCDC issue

victorien — Mon, 28 Apr 2014 13:44:36 GMT

If you need the recovery boot, you need to keep the same schematic as Evaluation Board. But if you don't use recovery and always supply to VDD5V, I thinks the best connection is to tie it to GND

Re: PSWITCH left unconnected and DCDC issue

dgotfroi — Mon, 28 Apr 2014 14:20:49 GMT

Many thanks for all. I had my answer :smileyhappy:.