how to find out the output of d flip flop

[vead]

when the value of flip flop input are known how to find out the flip flop output I want to find out the output of d flip flop

truth table

--------|------
D Clk Qn| Qn+1
--------|------
0 0 |
0 1 |
1 0 |
1 1 |


how to find out Qn ?
how to find out Qn+1?

 

[Tunelabguy]

You need to expand your truth table to include the value of CLK before and after a transition. Qn does not matter when deciding what Qn+1 will be. Qn+1 will be the same as D whenever CLK goes through a transition from 0 to 1, provided that value of D remained constant during the setup and hold times around the CLK transition. And Q will remain in that state until the next 0 to 1 transition on CLK. (Note: some D flip-flops use the opposite transition of CLK, from 1 to 0.)

 

[BradtheRad]

The link below will open an interactive simulation of a D flip-flop (master-slave configuration).

Click the single input (L or H) at extreme left. Watch to see at what time the output changes.

https://tinyurl.com/kwl4pgu

This is one of the circuits included in Falstad's animated simulator. Free to download and use at:

www.falstad.com/circuit

 

[vead]

if clock=1
--------------
D Clk |Qn
--------------
0 1 | 0
1 1 | 1

and if clock=0
D Clk |Qn
--------------
0 0 | 0
1 0 | 0

check out table if i am wrong correct me

 

[BradtheRad]

If we look closely at your table, it appears the same as an 'AND' gate's.

The D flip-flop is a clocked device. Its gates are configured to wait until a clock transition, to change state.

These scope traces demonstrate its behavior. Your truth table must show the same responses.