continuation of transistor flip flop design page 2

Now, next I build a two input "NAND" gate.

No design calculations here, just put it together, and through trial and error, pick the right resistor values, that work properly with the rest of the circuit.

I found that the 100K base resistors works fine for activating the "NAND" gate,
also by putting the 470K pull up resistor at the output, keeps the output more stable, from false triggering.

The 270K was used to represent the input impedance of the flip flop, so as to determine the right choice of component values, for the "NAND" gate.


1572204813678.png


Now by combining "NAND" gates and an inverter, at the input, to the flip flop, it now changes the flip flop from a (RS flip flop) to a (DATA flip flop), also known as a (D-flip flop).

First here is a logic diagram of a D-flip flop.


1572204819908.png


Now my design uses "NAND" gates due to the inversion process at the inputs of the flip flops, however the results are still the same in the performance of it acting as a D-flip flop.

Here is the schematic: using my choice of components, to perform the same function, as a D-flip flop.


1572204826861.png


Here is a video demo. of it working as a "D-flip flop"

"
"

The green LED's on top are the outputs, and the data and clock inputs are connected to the pushbutton switches.


next will be combining two of these D-flip flops, to make one complete "master-slave flip flop",
which is the main type used for all data handling.

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