There are four types of clock triggering that determine when a sequential circuit responds to input changes: negative level triggering, positive level triggering, positive edge triggering, and negative edge triggering. Negative level triggering occurs when a flip flop is triggered at the negative/low level of the clock pulse. Positive level triggering occurs when a flip flop is triggered at the positive/high level of the clock pulse. Positive edge triggering occurs when the output responds to input changes only at the rising edge of the clock pulse. Negative edge triggering occurs when the output responds to input changes only at the falling edge of the clock pulse.

1. CLOCK TRIGGERING
Amshal Ejaz
20-Arid-1669

2. CLOCK
Clock signal:
Clock signal is a periodic signal and its ON time and OFF time need not be the same.
We can represent the clock signal as a square wave, when both its ON time and OFF
time are same. This clock signal is shown in the following figure.
High low

3. TRIGGERING:
• The process of applying clock to any sequential circuit is
known as triggering.
• The number of cycle per second is called frequency.
• Time required for number of cycle completing in one second.

4. FOUR TYPE OF CLOCK TRIGGERING
1) Negative level triggering
2) Positive level triggering
3) Positive edge triggering
4) Negative edge triggering

5. NEGATIVE LEVEL TRIGGERING
If the flip flop is triggered at the negative level of the clock
pulse, then it is said to be negative/low level triggering.

6. POSITIVE LEVEL TRIGGERING
If the flip flop is triggered at the positive level of the
clock pulse, then it is said to be a positive/high level
triggering.

7. POSITIVE EDGE TRIGGERING
When the output responds to the change in the input only at the
positive edge of the clock pulse, then the clock pulse is said to be
a positive edge triggered.

8. NEGATIVE EDGE TRIGGERING
When the output responds to the change in the input only at
the negative edge of the clock pulse, then the clock pulse is
said to be a negative edge triggered.