On Fri, May 30, 2014 at 12:31 PM, Stéphane Goujet stephane.goujet@wanadoo.fr wrote:
On Fri, 30 May 2014, Luke Kenneth Casson Leighton wrote:
On Thu, May 29, 2014 at 11:20 PM, Stéphane Goujet stephane.goujet@wanadoo.fr wrote:
On Thu, 29 May 2014, Luke Kenneth Casson Leighton wrote:
BOM and schematic PDF are here, review appreciated.
I can get the BOM, but not the PDF : You don't have permission to access
sorted.
Thanks.
A few quick remarks:
*1* ACIN: should be renamed DCIN, I guess.
*2* PW_EN: when connected to U9 its wire has an output symbol. It should be an input symbol.
*3* PW_EN: not generated anywhere yet.
*4* resistors around U9: R53 and R54 have very high values (they are usually chosen around the range 10k-100k, not 100k-1M). Was there an advise to do so, or a reference design doing so ?
finally got round to looking at this, yes it's the reference design. the values are chosen to give the voltage required, there is a table (and a calculation) in the ref. design.
*5* RESET circuit: I do not quite understand it. First, because VCC-3V3 depends on PW_EN (U9 switching regulator). Second, because you seem to assert RESET (RESET#=0) when PW_EN==1: is this what you really want ? Third, because... what is RESET# used for ?
i'm going to remove it. poweroff will be "reset".