产品介绍

M74HC191 4 Bit Synchronous Binary Up/Down Counter

The M74HC191 is an high speed CMOS 4-BIT SYNCHRONOUS UP/DOWN COUNTER fabricated with silicon gate C2MOS technology.

State changes of the counter are synchronous with the LOW-to-HIGH transition of the Clock Pulse Input.

An asynchronous parallel load input overrides counting and loads the data present on the DATA inputs into the flip-flops, which makes it possible to use the circuits as programmable counters. A count enable input serves as the carry/borrow input in multi-stage counters. Control input, Down/ Up, determines whether a circuit counts up or down. A MAX/MIN output and a Ripple Clock output provide overflow/underflow indication and make possible a variety of methods for generating carry/borrow signals in multi-stage counter applications.

All inputs are equipped with protection circuits against static discharge and transient excess voltage

技术特性

• HIGH SPEED :
  • fMAX = 61 MHz (TYP.) at VCC = 6V
• LOW POWER DISSIPATION:
  • ICC =4µA(MAX.) at TA=25 °C
• HIGH NOISE IMMUNITY:
  • VNIH = VNIL = 28 % VCC (MIN.)
• SYMMETRICAL OUTPUT IMPEDANCE:
  • |IOH| = IOL = 4mA (MIN)
• BALANCED PROPAGATION DELAYS:
  • tPLH tPHL
• WIDE OPERATING VOLTAGE RANGE:
  • VCC (OPR) = 2V to 6V
• PIN AND FUNCTION COMPATIBLE WITH 74 SERIES 191

M74HC191 订购信息

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