20.09.2005, 08:55 PM
Hi guys,
sorry, my deutsch is much worse vs english.It's only one forum about 8939, which i found today. I've try to evaluate TDA8939TH/N1C (N4D5W9 HSE04391X), and slightly disappointed about Ii(bias)which claimed in the TDA8939_1.pdf <10uA , but in my case the input bias 20 times bigger! I used symmetrical supply +/-25V, and it seems each of the comparators inputs have pull-down resistors around 120KOhm (connected to the Vssa, and my Ohm-meter shows 123Kohm too). Anyone has noticed too? Well, it would be great, if someone will make measurement of the impedance between #1 and #2 pins etc, and report here. Thank you!
BTW, Philips answered today: There have not been any changes to the device..
sorry, my deutsch is much worse vs english.It's only one forum about 8939, which i found today. I've try to evaluate TDA8939TH/N1C (N4D5W9 HSE04391X), and slightly disappointed about Ii(bias)which claimed in the TDA8939_1.pdf <10uA , but in my case the input bias 20 times bigger! I used symmetrical supply +/-25V, and it seems each of the comparators inputs have pull-down resistors around 120KOhm (connected to the Vssa, and my Ohm-meter shows 123Kohm too). Anyone has noticed too? Well, it would be great, if someone will make measurement of the impedance between #1 and #2 pins etc, and report here. Thank you!
BTW, Philips answered today: There have not been any changes to the device..