| ??? 09/22/05 15:08 Read: times |
#101395 - Fan-out specification Responding to: ???'s previous message |
Jan said:
No, it is not, unless you specify the manufacturer.
The most common value is 0.3V. It depends more on Fan-out specification, than on manufacturer: Taking into consideration a Fan-out of ten 74TTL-loads, the low-voltage noise margin of 74TTL-family is 400mV. The same with 74LS-chips: Refering to a Fan-out of ten 74LS-loads, the low-voltage noise margin of 74LS-family is 400mV. A word to 'hair-picking': You CAN have success with your diode solution. But for a professional this is not a real option. A professional has (painfully) learned over decades of designing, that there's absolutely no gain in reducing the noise margins! And a professional for this reason does not want to discuss any further such solutions, where the noise margins are reduced somehow, because he (painfully) has learned that he cannot trust these 'solutions', when he urgently need to trust them. A professional insists on having all the noise margin the manufacturer of chips delivers. And the professional gets fired if his project fails because of a not professional like design solution... So, Jan, please don't feel offended by my insistence! As I said, I will not comment on the topic itself any more. Why that? Let the discussion go on... I accept your point-of-view, if you accept mine. Kai |
