Is there anyone out there who has expert knowledge of upc1237 ?



Can the upc1237 be driven by 50 volts AC (which is rectified to 70 VDC as Vcc).

According to the datasheet formulas, for the above voltages, R ac should be 32k ohms and R vcc should be 19k ohms.  Since pin 8 has a shunt regulator, in theory, it should work.  But before I connect such voltages and blow up the chip, I wanted to be absolutely sure.

Has anyone ACTUALLY ever used those high voltage values ?

I already have this available on the power supply and did not want to get another transformer and rectify it.

Thanks
128x128cakyol
Thanks,

You are right.  It is probably much safer to go with maybe an external 24 volt transformer giving about rectified 35 VDC.  This way, I can keep the capacitors at lower voltages (hence a bit cheaper) anyway.

Thanks

I’m not an expert, but I think those upc1237 currently available in the market are come from Taiwan, according to their data sheet, the absolute max Vcc rating is 60V. Maybe drop the voltage to 25 to 45V using zener diodes is a safer way to go.

http://www.unisonic.com.tw/datasheet/UPC1237.pdf