4045
21-bit asynchronous binary counter with oscillator and reset input.
Only two 3% duty cycle outputs (180` out of phase) from the last counter stage
are available. Can be used to generate a 1Hz clock signal using a 2.097152MHz
crystal. P and N MOSFET source connections from the oscillator inverter are
brought out of the package to allow the use of source resistors, but usually
pS=VCC and nS=GND.
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Ich nehme an der Typ 4040 ist besser geeignet: Zähler 12 bit alle 12 herausgeführt