M74HC390B1R屬于集成電路（IC）的計數(shù)器除法器。由意法半導(dǎo)體集團制造生產(chǎn)的M74HC390B1R計數(shù)器，除法器計數(shù)器和除法器 IC 是數(shù)字邏輯器件，可對輸入發(fā)生的邏輯轉(zhuǎn)換進行計數(shù)，然后使用多個并行輸出重新發(fā)送累加的計數(shù)，和/或生成單個輸出信號轉(zhuǎn)換，從而對應(yīng)用某些整數(shù)數(shù)量輸入信號轉(zhuǎn)換進行響應(yīng)。除了簡單的事件計數(shù)，它們還可用于各種頻率合成應(yīng)用。

DESCRIPTION

The M54/74HC390 is a high speed CMOS DUAL DECADE COUNTER fabricated in silicon gate C2MOS technology. It has the same high speed performance of LSTTL combined with true CMOS low power consumption.

This dual decade counter contains two independent ripple carry counters. Each counter is composed of a divide-by-two and divide-by-five counter. The divide-by-two and divide-by-five counters can be cascaded to form dual decade, dual biquinary, or various combinations up to a single divide-by-100 counter.

■ HIGH SPEED fMAX = 84 MHz (TYP.) AT VCC = 5 V

■ LOW POWER DISSIPATION ICC = 4 μA (MAX.) AT TA = 25 °C

■ HIGH NOISE IMMUNITY VNIH = VNIL = 28 VCC (MIN.)

■ OUTPUT DRIVE CAPABILITY 10 LSTTL LOADS

■ SYMMETRICAL OUTPUT IMPEDANCE |IOH| = IOL = 4 mA (MIN.)

■ BALANCED PROPAGATION DELAYS tPLH = tPHL

■ WIDE OPERATING VOLTAGE RANGE VCC (OPR) = 2 V TO 6 V

■ PIN AND FUNCTION COMPATIBLE WITH 54/74LS390