LEDC with open drain outputs
Thankyouverymuchfortheadvice.Withthe`pinMode(...)`IalreadydidthisonenESP32quiteatimenow(ayear).
...theESDprotectionwilllimityourGPIOvoltagetoabitabove3.3V...Icouldmeasure4,85Vwithmyoscilloscope,seesnapshot:-Rpu=10kOhmonGPIO33onanESP32S2(Olimexboard):PWMpulseOpendrainto5Vpwm_pulse.png(85.44KiB)Viewed6135timesDidIruintheESDprotection?Ijustfoundthethread:"Opendrainoutputmaxvoltage"[1]wherethisisalsomentioned.
SinceIamcurious:
IcouldnotfindthespecsofthemaximumratingsofGPIOsdirectlyoroftheESDprotectioninthetechnicalreferencemanual[2]anddatasheet[3]fortheESP32-S2lookingtoElectricalspecifications.Sopleasecanyouhintmetoit?
ButIfoundin"ReliabilityQualifications"at[4]"Latch-up(Over-voltagetest)with1.5×VDDmax,
whichwouldbe3.6V*1.5=5,4Vasmaximumrating,soIcouldworkwith5V,
Iwouldbenicetoknow,soIcanchangesafelymydesign.
mfgwinfried
[1]viewtopic.php?f=12&t=18477&p=68827&hilit=Open+Drain[2]https://www.espressif.com/sites/default...ual_en.pdf[3]https://www.espressif.com/sites/default...eet_en.pdf[4]https://www.espressif.com/sites/default..._en.pdf#40