Details

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BUY 74LS74 https://www.utsource.net/itm/p/12591918.html

Parameter	Symbol	Min	Typ	Max	Unit
Supply Voltage	VCC	4.75	5	5.25	V
Output High Voltage	VOH	2.7	-	VCC-0.5	V
Output Low Voltage	VOL	0	-	0.4	V
Input High Voltage	VIH	2	-	VCC	V
Input Low Voltage	VIL	0	-	0.8	V
Propagation Delay Time	tpd	-	22	34	ns
Setup Time	tsu	20	-	-	ns
Hold Time	th	5	-	-	ns
Maximum Clock Frequency	fMAX	-	14	20	MHz
Power Dissipation (per package)	PD	-	150	-	mW

Instructions for Using 74LS74:

1. Power Supply:

   • Connect V_CC to +5V and GND to 0V.
   • Ensure the supply voltage is within the specified range (4.75V to 5.25V) to avoid damage.

2. Pin Configuration:

   • Pin 1 (QA): Output of the first flip-flop.
   • Pin 2 (D1): Data input of the first flip-flop.
   • Pin 3 (CLK1): Clock input of the first flip-flop.
   • Pin 4 (CLR1): Active-low clear input of the first flip-flop.
   • Pin 5 (PR1): Active-low preset input of the first flip-flop.
   • Pin 6 (GND): Ground.
   • Pin 7 (PR2): Active-low preset input of the second flip-flop.
   • Pin 8 (CLR2): Active-low clear input of the second flip-flop.
   • Pin 9 (CLK2): Clock input of the second flip-flop.
   • Pin 10 (D2): Data input of the second flip-flop.
   • Pin 11 (QB): Output of the second flip-flop.
   • Pin 12 (V_CC): Power supply.
   • Pin 13 (QAB): Complement output of the first flip-flop.
   • Pin 14 (QBB): Complement output of the second flip-flop.

3. Operation:

   • Clock Input (CLK): The flip-flop changes state on the rising edge of the clock signal.
   • Preset (PR) and Clear (CLR): These inputs are active-low. When PR is low, the flip-flop sets the output to high. When CLR is low, the flip-flop sets the output to low.
   • Data Input (D): The data input determines the state of the flip-flop on the next clock pulse.
   • Setup and Hold Times: Ensure that the data and control signals meet the setup and hold time requirements relative to the clock edge to avoid metastability.

4. Propagation Delay:

   • The propagation delay time (t_pd) is the time it takes for the output to change after the clock edge. It typically ranges from 22ns to 34ns.

5. Power Dissipation:

   • The maximum power dissipation per package is 150mW. Ensure proper heat dissipation if operating at high frequencies or in high ambient temperatures.

6. Storage and Handling:

   • Store the IC in a static-protective bag to prevent electrostatic discharge (ESD) damage.
   • Handle the IC by the edges and avoid touching the pins directly.

7. Testing:

   • Before integrating the 74LS74 into a circuit, test its functionality using a simple test circuit to ensure it is working correctly.

By following these instructions, you can effectively use the 74LS74 dual D-type positive-edge-triggered flip-flop in your digital circuits.

(For reference only)