HD74HC93 Datasheet, PDF (5/8 Pages) Hitachi Semiconductor – 4-bit Binary Counter

HD74HC93
Test Circuit
VCC
Input
Pulse generator
Zout = 50 Ω
VCC
Output
A
B
R0(1)
R0(2)
QA
Output
C_L = 50 pF
QB
Output
C_L = 50 pF
QC
Output
C_L = 50 pF
QD
C_L = 50 pF
Note: C_L includes the probe and jig capacitance.
Waveforms
• Waveform – 1
Count
Down
QA
QB
QC
QD
tr
tf
90%
10%
50%
10%
tPHL (Measure at tn+2)
50%
tPLH (Measure at tn+1)
90%
50%
10%
tTHL
tPHL (Measure at tn+4)
90%
50%
10%
tTLH
tPLH (Measure at tn+2)
90%
50%
10%
90%
50%
10%
tTHL
tPHL (Measure at tn+8)
tTLH
tPLH (Measure at tn+4)
90%
50%
10%
90%
50%
10%
tTHL
tPHL (Measure at tn+16)
tTLH
tPLH (Measure at tn+8)
90%
50%
10%
50%
10%
90%
tTHL
tTLH
Notes: 1. Input waveform: PRR ≤ 1 MHz, Zo = 50 Ω, t_r ≤ 6 ns, t_f ≤ 6 ns
2. tn is reference bit time when all outputs are low.
V_CC
0V
VOH
VOL
VOH
VOL
VOH
VOL
VOH
VOL
Rev.2.00, Oct 06, 2005 page 5 of 7