HD74HC668 Datasheet, PDF (9/14 Pages) Hitachi Semiconductor – Synchronous UP/Down Decade,4-bit binary Counter

HD74HC668/HD74HC669
AC Characteristics (C_L = 50 pF, Input t_r = t_f = 6 ns)
Ta = 25°C
Ta = –40 to
+85°C
Item
Maximum clock
Frequency
Symbol
f _max
V_CC (V)
2.0
4.5
Min Typ Max Min
——5 —
— — 27 —
Max Unit Test Conditions
4
MHz
21
6.0
— — 32 — 25
Propagation delay t_PLH
time
t _PHL
2.0
— — 200 — 250 ns Clock to Ripple carry out
4.5
— — 40 — 50
6.0
— — 34 — 43
t _PLH
2.0
— — 225 — 280 ns Clock to Q
t _PHL
4.5
— — 45 — 56
6.0
— — 38 — 48
t _PLH
2.0
— — 150 — 190 ns Enable T to Ripple carry out
t _PHL
4.5
— — 30 — 38
6.0
— — 26 — 33
t _PLH
2.0
— — 200 — 250 ns U/D to Ripple carry out
t _PHL
4.5
— — 40 — 50
6.0
— — 34 — 43
Pulse width
t_w
2.0
80 — — 100 — ns
4.5
16 — — 20 —
6.0
14 — — 17 —
Setup time
t _su
2.0
100 — — 125 — ns Data to Clock
4.5
20 — — 25 —
6.0
17 — — 21 —
t _su
2.0
150 — — 190 — ns Enable P, T to Clock
4.5
30 — — 38 —
6.0
26 — — 33 —
t _su
2.0
150 — — 190 — ns Loadk to Clock
4.5
30 — — 38 —
6.0
26 — — 33 —
t _su
2.0
150 — — 190 — ns U/D to Clock
4.5
30 — — 38 —
6.0
26 — — 33 —
9