HD74HC298 Quad. 2-input Multiplexers (with storage) 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 pF) 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 Outputs QA QB QC QD L a1 b1 c1 d1 H a2 b2 c2 d2 QA0 QB0 QC0 QD0 Word Select X Clock H HD74HC298 Pin Arrangement Data inputs B2 1 16 VCC A2 2 A2 A1 3 B1 B2 QA 15 QA A1 QB 14 QB 4 B1 QC 13 QC C2 5 C2 QD 12 QD D2 6 D2 D1 7 D1 GND 8 Outputs CK 11 Clock WS 10 Word select C1 9 (Top view) 2 Data input C1 HD74HC298 DC Characteristics Ta = –40 to +85°C Ta = 25°C Item Symbol VCC (V) Min Typ Max Min Max Unit Input voltage VIH 2.0 1.5 — — 1.5 — V 4.5 3.15 — — 3.15 — 6.0 4.2 — — 4.2 — 2.0 — — 0.5 — 0.5 4.5 — — 1.35 — 1.35 6.0 — — 1.8 — 1.8 2.0 1.9 2.0 — 1.9 — 4.5 4.4 4.5 — 4.4 — 6.0 5.9 6.0 — 5.9 — 4.5 4.18 — — 4.13 — I OH = –4 mA 6.0 5.68 — — 5.63 — I OH = –5.2 mA 2.0 — 0.0 0.1 — 0.1 4.5 — 0.0 0.1 — 0.1 6.0 — 0.0 0.1 — 0.1 4.5 — — 0.26 — 0.33 I OL = 4 mA 6.0 — — 0.26 — 0.33 I OL = 5.2 mA VIL Output voltage VOH VOL Test Conditions V V V Vin = VIH or VIL I OH = –20 µA Vin = VIH or VIL I OL = 20 µA Input current Iin 6.0 — — ±0.1 — ±1.0 µA Vin = VCC or GND Quiescent supply current I CC 6.0 — — 4.0 40 µA Vin = VCC or GND, Iout = 0 µA — 3 HD74HC298 AC Characteristics (CL = 50 pF, Input tr = tf = 6 ns) Ta = –40 to +85°C Ta = 25°C VCC (V) Min Typ Max Min Max Unit Test Conditions Propagation delay t PLH 2.0 — — 170 — 215 ns Clock to Q time 4.5 — 19 34 — 43 6.0 — — 29 — 37 2.0 80 — — 100 — ns Clock 4.5 16 10 — 20 — 6.0 14 — — 17 — 2.0 150 — — 190 — 4.5 30 16 — 38 — 6.0 26 — — 33 — 2.0 5 — — 5 — 4.5 5 –5 — 5 — 6.0 5 — — 5 — Item Pulse width Setup time Hold time Symbol t PHL tw t su th Output rise/fall t TLH 2.0 — — 75 — 95 time t THL 4.5 — 5 15 — 19 6.0 — — 13 — 16 — — 5 10 — 10 Input capacitance 4 Cin ns ns ns pF Unit: mm 19.20 20.00 Max 1 7.40 Max 9 6.30 16 8 1.3 0.48 ± 0.10 2.54 Min 5.06 Max 2.54 ± 0.25 0.51 Min 1.11 Max 7.62 + 0.13 0.25 – 0.05 0° – 15° Hitachi Code JEDEC EIAJ Weight (reference value) DP-16 Conforms Conforms 1.07 g Unit: mm 10.06 10.5 Max 9 1 8 1.27 *0.42 ± 0.08 0.40 ± 0.06 0.10 ± 0.10 0.80 Max *0.22 ± 0.05 0.20 ± 0.04 2.20 Max 5.5 16 0.20 7.80 +– 0.30 1.15 0° – 8° 0.70 ± 0.20 0.15 0.12 M *Dimension including the plating thickness Base material dimension Hitachi Code JEDEC EIAJ Weight (reference value) FP-16DA — Conforms 0.24 g Unit: mm 9.9 10.3 Max 9 1 8 0.635 Max *0.42 ± 0.08 0.40 ± 0.06 0.15 *0.22 ± 0.03 0.20 ± 0.03 1.27 0.11 0.14 +– 0.04 1.75 Max 3.95 16 0.10 6.10 +– 0.30 1.08 0° – 8° 0.67 0.60 +– 0.20 0.25 M *Dimension including the plating thickness Base material dimension Hitachi Code JEDEC EIAJ Weight (reference value) FP-16DN Conforms Conforms 0.15 g