i have ic tester (gw instk gut-6600) that give pass to both ics as 4066 and fail both ics as 4016 and tested more than one new 4016.I do not the reason?
"Both" suggests you have two ICs. If both pass with tester set "4066" and both fail with tester set "4016", this suggests they are both 4066 type. Or do you mean that if you (1) set tester to "4016" and (2) put in a "known" 4016 and next a "known" 4066, BOTH fail?? Do you question working of tester or ICs here??