Flip Flop D-Type Bus Interface Pos-Edge 3-ST 1-Element 20-Pin SOIC T/R

The ’HC374, ’HCT374, ’HC574, and ’HCT574 are octal D-type flip-flops with 3-state outputs and the capability to drive 15 LSTTL loads. The eight edge-triggered flip-flops enter data into their registers on the LOW to HIGH transition of clock (CP). The output enable (OE) controls the 3-state outputs and is independent of the register operation. When OE is HIGH\, the outputs are in the high-impedance state. The 374 and 574 are identical in function and differ only in their pinout arrangements.

Buffered Inputs

Common Three-State Output Enable Control

Three-State Outputs

Bus Line Driving Capability

Typical Propagation Delay (Clock to Q) = 15ns at V_CC = 5V, C_L = 15pF, T_A = 25°C

Fanout (Over Temperature Range)

• Standard Outputs...10 LSTTL Loads
• Bus Driver Outputs...15 LSTTL Loads

Wide Operating Temperature Range...–55°C to 125°C

Balanced Propagation Delay and Transition Times

Significant Power Reduction Compared to LSTTL Logic ICs

HC Types

• 2V to 6V Operation
• High Noise Immunity: N_IL = 30%, N_IH = 30% of V_CC at V_CC = 5V

HCT Types

• 4.5V to 5.5V Operation
• Direct LSTTL Input Logic Compatibility, V_IL = 0.8V (Max), V_IH = 2V (Min)
• CMOS Input Compatibility, I_l = 1µA at V_OL, V_OH