Closed hartytp closed 4 years ago
Maybe add a schematic annotation/design variant for 60Hz?
if we load both outputs with 50Ohm, we end up with 1W The comparator already has hysteresis, I added a DNP capacitor Right, I meant LV125 which works at 5V and is capable of driving 100Ohm loads. I added a 47uF cap to the output buffer supply + FB. Not worth increasing the BOM with a tantalum cap.
@gkasprow Aren’t there already tantalum caps after the rectifier (not that it matters, I’m happy either way).
It’s 500mW max isn’t it since it’s 2.5V AC into 100 ohm in two channels?
Anyway I’m happy to move to manufacture when you are.
Thanks for the nice work on this :)
Yes, 500mW dissipates on the load. Add the LDO efficiency :)
Oops!
Oh, OK, I asumed permanent state H. Of course we have 50% duty cycle.
For anyone following: the plan is to get TS to produce a batch shortly. Contact Greg/Pawel if you're interested...
the plan is to get TS to produce a batch shortly
Will you post a final design for review or do you need to get this off yesterday (not a huge deal but always good to have more eyes)?
can you add a suitable AC/AC adaptor with the right connector to the schematic/BOM so we make sure all users use the same part (less work to debug than if everyone picks their own!)
Good idea but you need one for each region. This one looks readily available in the US. It has a 2.1x5.5mm plug as suggested. It's 11mm long - does that length work?
I've definitely seen those wall wart transformers put out higher than specified voltage under light load. Looks like the regs can take 36V which should be plenty, but might be worth selecting caps with a similar rating if you didn't already.
the schematics are in the repo
Will you post a final design for review or do you need to get this off yesterday (not a huge deal but always good to have more eyes)?
There is no mad rush, but I need to keep things moving through my to do list for sanity's sake...
I've definitely seen those wall wart transformers put out higher than specified voltage under light load. Looks like the regs can take 36V which should be plenty, but might be worth selecting caps with a similar rating if you didn't already.
Yes, good point. @gkasprow are you happy that the OpAmp circuit will still function happily if the voltage comes out a bit high?
Good idea but you need one for each region. This one looks readily available in the US. It has a 2.1x5.5mm plug as suggested. It's 11mm long - does that length work?
The 722RA you are using mates with the S760 which is 9.5mm long, so this will work.
the schematics are in the repo
Does IC8 need a 10nF decoupling cap? Other than that, I didn't see anything else.
we don't want the voltage to rise to 35V - the LDOs won't dissipate that much of power. Let's keep the capacitors as they are now.
looking at https://github.com/sinara-hw/Line_trigger/issues/2#issuecomment-695365925
I'm not going to look at the active filter topology / component selection in detail. The transfer function you posted looked sensible.
Otherwise, looks good to me! Let's get it made :)