Counter Dual 4-Bit Binary UP 16-Pin SOIC T/R

The CD74HC4518 is a dual BCD up-counter. The ’HC4520 and CD74HCT4520 are dual binary up-counters. Each device consists of two independent internally synchronous 4-stage counters. The counter stages are D-type flip-flops having interchangeable CLOCK and ENABLE lines for incrementing on either the positive-going or the negative-going transition of CLOCK. The counters are cleared by high levels on the MASTER RESET lines. The counter can be cascaded in the ripple mode by connecting Q3 to the ENABLE input of the subsequent counter while the CLOCK input of the latter is held low.

Positive or Negative Edge Triggering

Synchronous Internal Carry Propagation

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