74LS74 Dual D-Type Flip-Flop

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The 74LS series of integrated circuits (ICs) was one of the most popular logic families of transistor-transistor logic (TTL) logic chips. 74LS series is a bipolar, low-power Schottky IC. 74LS74 Dual D-Type Flip-Flop contains two independent D-type positive-edge-triggered flip-flops. A low level at the preset or clear inputs sets or resets the outputs regardless of the levels of the other inputs. When preset and clear are inactive (high), data at the D input meeting the setup time requirements are transferred to the outputs on the positive-going edge of the clock pulse. Clock triggering occurs at a voltage level and is not directly related to the rise time of the clock pulse. Following the hold-time interval, data at the D input may be changed without affecting the levels at the outputs.

74LS74 Features

  • Two Independent Negative Edge Triggered JK Flip-Flops
  • Standard Pin Arrangement
  • Fast Switching Times
  • Operating Temperature up to 70°C
  • Standard TTL Switching Voltages

74LS74 Specifications

Supply Voltage4.75 – 5.25Vdc
Maximum Clock Frequency40Mhz
Power Dissipation2mW/gate @100kHz
Minimum Output Current8mA
Propagation Delay10nS
Fan Out (TTL Loads)20

74LS74 Pinout Diagram

74LS74 Pin Description

Pin NoPin NameDescription
1CDClock Pin
2DD Flip Flop Pin
3CPClear Pin
4SDSerial Data Pin
5Q1The output logic level Q1
6Q1′The output logic level Q1′
7GNDGround
8Q2′The output logic level Q2′
9Q2The output logic level Q2′
10SD Serial Data Pin
11CP Clear Pin
12D D Flip Flop Pin
13CD Clock Pin
14VCCPositive Supply

74LS74 Circuit

Applications

  • Create delay-lines

74LS74 Alternative Equivalent

74LS273, 74LS373

Download 74LS74 Dual D-Type Flip-Flop Datasheet from the link given below.