Johnny's homebuilt 8080 CPU corner (and other stuff, maybe)

 

Simple comparison between some different transistors, with and without a Baker Clamp (1N4148).

Note that the signal has gone through two transistors, so the actual delay per transistor is only half of what is shown.

 

Input signal is 1MHz, base resistor is 8K2 and collector resistor is 1K. As usual, the input diode is BAT42.

 

The goal here is to find a transistor with the smallest propagation delay.

Switching speed (high frequency) isn't that important. Propagation delay, however, is.

 

At the bottom you will find my new favourite transistor: KSP10

Yellow trace = Probe 1 Green trace = Probe 2

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