HD74HC243 Datasheet, PDF (5/7 Pages) Renesas Technology Corp – Quad. Bus Transceivers (with noninverted 3-state outputs)

HD74HC243
Test Circuit
VCC
Input
Pulse Generator
Zout = 50 Ω
VCC
GAB
Output
B or A
GBA
1 k Ω _S1
C_L =
50 pF
OPEN
GND
V_CC
A or B
TEST
t_PLH / t _PHL
t_ZH/ t _HZ
t_ZL / t _LZ
S1
OPEN
GND
V_CC
Waveforms
Note : 1. C_L includes probe and jig capacitance.
• Waveform – 1
Input A or B
tr
10 %
90 %
50 %
t_PLH
tf
90 %
50 %
10 %
t_PHL
Output B or A
50 %
10 %
90 %
90 %
50 %
10 %
t_TLH
t_THL
• Waveform – 2
tf
tr
GAB
or
GBA
90 %
50 %
10 %
t_ZL
10 %
90 %
50 %
t_LZ
Waveform - A
Waveform - B
50 %
t_ZH
50 %
10 %
t_HZ
90 %
V_CC
GND
V_OH
V_OL
V_CC
GND
V_OH
V_OL
V_OH
V_OL
Notes : 1. Input waveform : PRR ≤ 1 MHz, duty cycle 50%, t_r ≤ 6 ns, t_f ≤ 6 ns
2. Waveform– A is for an output with internal conditions such that the
output is low except when disabled by the output control.
3. Waveform– B is for an output with internal conditions such that the
output is high except when disabled by the output control.
4. The output are measured one at a time with one transition per measurement.
Rev.2.00 Jan 31, 2006 page 5 of 6