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4013 D-Type Flip Flop

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Here is the symbol of a D Type Flip Flop.

D Type Flip Flop.gif 4013.gif

Data Latch

D Type Flip Flop Latch.gif

Frequency Divider

On the rising edge of the clock pulse, D is copied to Q.
Since NOT Q is connected to D, the data is inverted on each rising edge.
This has the effect of dividing the frequency by two.

D Type Flip Flop Counter 1.gif

Switch Debounce and a One Bit Counter - Build This

The two NAND gates are connected as a Bistable Flip Flop. This is used to debounce the switch pulses. The 4013 D Type Flip Flop is wired as a one bit binary counter. Each time the Bistable LED comes on (the rising edge), the counter LED changes state. This counter counts 0, 1, 0, 1, Etc.

For the Falstad Circuit Simulation, CTRL+Click One Bit Counter
In options, check European Resistors and uncheck Conventional Current.
Click the switch to clock the counter.

Alternatively view One_Bit_Counter.txt.
Save or copy the text on the web page. Import the saved or copied text into the Falstad simulator.

Here is the new HTML5 Simulator Site.

Divide by Two

This is a slightly odd circuit because two different families of logic chips are being used.

Debounce and Counter Circuit Photo

A Two Bit Counter - Build this if you have time.

Two Bit Counter




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