Genome wrote:

"Eeyore" wrote in message
Genome wrote:

However, I did work out an equation for the gain of your compound
differential pair that seems fairly close to the mark.....

Bpnp = 05 Av = 56.9dB
Bpnp = 10 Av = 60.6dB +3.7dB
Bpnp = 20 Av = 64.4dB +3.8dB
Bpnp = 40 Av = 67.8dB +3.4dB
Bpnp = 80 Av = 70.5dB +2.7dB

That looks, more or less, like the gain depends on Beta in the manner
suggested.

You reckon the beta is 5 ? Try an average figure of around 200.

Those numbers look way out anyway.


I suppose that's why I stepped it from 5 to 80.

Of course you'll ignore anything in an effort to try and prove how good you
think others should think you are.

Next time you edit a post to suit yourself try and get it right. You should
have removed the figures for Bnpn 5.

What are you rambling on about now ?


The numbers come from an LTspice simulation but I suppose quoting them gives
you a chance to criticise once more in your never ending effort to prove how
good we should think you are.

Perhaps you should change your nym.....

Perhaps you should look at this data sheet for a BC549 ? Minimum beta @ 2mA is
*420* !

Graham