HD74LS242 Datasheet, PDF (4/7 Pages) Hitachi Semiconductor – Quadruple Bus Transceivers(with three-state outputs)

HD74LS242
Testing Method
Test Circuit
4.5 V
Input
P.G.
Zout = 50 Ω
V_CC
GAB
R_L
Output _S1
1B ^S3
1A
GBA
C_L ^{5 kΩ}
S₂
Notes:
1. 2A-2B, 3A-3B, 4A-4B are identical to abobe load circuit.
2. C_L includes probe and jig capacitance.
3. S₃ is a input-output switch.
4. All diodes are 1S2074(H).
Waveforms 1
t_TLH
t_THL
3V
Input A
90 %
90 %
(or B)
10 %
1.3 V
t_PHL
1.3 V
10 %
0V
t_PLH
V_OH
Output B
(or A)
1.3 V
1.3 V
V_OL
Note: Input pulse: t_TLH ≤ 15 ns, t_THL ≤ 6 ns, PRR = 1 MHz, duty cycle 50%
Rev.3.00, Jul.15.2005, page 4 of 6