1.st7538 datasheet says c_minus should be connected to vdc and c_plus to sgnd. but in this demo board , things seems just opposite. then , which connection is right ?
2.As R14 is 1kohm, what's the best value of R12 ? can it be more than 10kohm? 3.are c17 an c18 right ? can they work stably as they being not equal?? thanks for your reply!! contact me : my msn :