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Re: Once-over before sending off the PCB ?
Posted: Thu Jan 25, 2018 9:01 am
by eez-open
Sorry for misunderstanding about reset. C44 should be fine. If necessary you can increase it to 47 or 100 nF.
You can change default layers color. There is not a lots of choice but still you can manage to set something that is easier to follow. Select Display option, and use Change on layer that is selected.
Re: Once-over before sending off the PCB ?
Posted: Thu Jan 25, 2018 7:10 pm
by SpacedCowboy
Sorry for misunderstanding about reset. C44 should be fine. If necessary you can increase it to 47 or 100 nF.
And this is where my understanding breaks down :( I don't see how a capacitor that's not connected to a supply voltage can keep /MR high ?
[sigh] So I really ought to read the datasheet - "Driving the manual reset pin (MR) low asserts RESET.
MR is internally tied to VDD by a 90- kΩ pull-up resistor."
You can change default layers color. There is not a lots of choice but still you can manage to set something that is easier to follow. Select Display option, and use Change on layer that is selected.
Excellent, thank you :) That's good to know - I really ought to have looked! :)
Cheers
Simon
Re: Once-over before sending off the PCB ?
Posted: Thu Jan 25, 2018 10:43 pm
by eez-open
SpacedCowboy wrote:Sorry for misunderstanding about reset. C44 should be fine. If necessary you can increase it to 47 or 100 nF.
And this is where my understanding breaks down :( I don't see how a capacitor that's not connected to a supply voltage can keep /MR high ?
[sigh] So I really ought to read the datasheet - "Driving the manual reset pin (MR) low asserts RESET.
MR is internally tied to VDD by a 90- kΩ pull-up resistor."
Capacitor is here not to keep MR high but to filter possible noise. Pull-up is inside as you found.