HD74HC298 Datasheet | Hitachi Semiconductor

Description This circuit is controlled by the signals word select and clock. When the word select input is taken low word 1 (A 1, B1, C1 and D 1) is presented to the inputs of the flip-flops, and when word select is high word 2 (A 2, B 2, C2 and D2) is presented to the inputs of the flip-flops. The selected word is clocked to the output terminals on the negative edge of the clock pulse. Features - - - - - High Speed Operation: tpd (Clock to Q) = 19 ns typ (CL = 50 p F) High Output Current: Fanout of 10 LSTTL Loads Wide Operating Voltage: VCC = 2 to 6 V Low Input Current: 1 µA max Low Quiescent Supply Current: ICC (static) = 4 µA max Function Table Inputs Word Select L H X H Clock Outputs QA a1 a2 QA0 QB b1 b2 QB0 QC c1 c2 QC0 QD d1 d2 QD0 Pin Arrangement B2 A2 A1 Data inputs B1 C2 D2 D1 GND 1 2 3 4 5 6 7 8 A2 A1 B1 C2 D2 D1 B2 QA QB QC QD CK WS 16 VCC 15 QA 14 QB Outputs 13 QC 12 QD 11 Clock 10 Word select 9 Data input C1 C1 (Top view) DC Characteristics Ta = 25°C Item Input voltage Symbol VIH Ta = - 40 to +85°C Max - - - 0.5 1.35 1.8 - - - - - 0.1 0.1 0.1 0.33 0.33 ±1.0 40 µA µA I OL = 4 m A I OL = 5.2 m A Vin = VCC or GND Vin = VCC or GND, Iout = 0 µA V I OH = - 4 m A I OH = - 5.2 m A Vin = VIH or VIL I OL = 20 µA V Vin = VIH or VIL I OH = - 20 µA V Unit V Test Conditions VCC (V) Min Typ Max Min 2.0 4.5 6.0 1.5 - 3.15 - 4.2 - - - - - - - - - - 0.5 1.5 3.15 4.2 - VIL 2.0 4.5 6.0 - 1.8 - 1.9 4.4 5.9 4.13 5.63 - - - Output...