Re: Simple transistor NOT gate

On Feb 4, 11:21 am, "Bob Monsen" <rcmon...@xxxxxxxxx> wrote:
Alan:
   Your transtor is saturating when on, and it is probably very slow to come
out of saturation. Try putting a diode from base to collector; that will
keep it from saturating. Here is the circuit:

VCC --------------------------.
                              |
                              |
                             .-.
                             | | 10k
                             | |
                             '-'
                              |
                              |
                    .--->|----o----- out
                    |         |
                    |         |
                    |         |
            1k      |         |
            ___     |       |/
 in -------|___|----o-------|
                            |>
                              |
                              |
GND --------------------------'
(created by AACircuit v1.28.6 beta 04/19/05www.tech-chat.de)

This trick is called a 'baker clamp' for some reason. The diode prevents the
transistor from saturating, thereby increasing the speed at which it can
turn off. This circuit probably won't do more than a few MHz, but you never
know.

Regards,
 Bob Monsen

Hi Bob,

Your circuit works like magic. I am going to read more about this
'baker clamp' diode. Was it mentioned in the AoE?

Thanks again for your help!

Allen
.

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