HD74LS148 Datasheet, PDF (4/6 Pages) Hitachi Semiconductor – 8-line-to-3-line Octal Priority Encoders

HD74LS148
Testing Method
Test Circuit
4.5V
P.G.
Zout = 50Ω
Input
V_CC Output
RL ^{Load circuit 1}
EO
CL
EI
0
Output
1
GS
Same as Load Circuit 1.
2
Output
3
A0
Same as Load Circuit 1.
4
Output
5
A1
Same as Load Circuit 1.
6
Output
7
A2
Same as Load Circuit 1.
Notes: 1. C_L includes probe and jig capacitance.
2. All diodes are 1S2074(H).
Waveform
t_TLH
t_THL
90%
90%
3V
Input
1.3 V
1.3 V
10%
10%
0V
t_PLH
t_PHL
In phase output
1.3 V
t_PHL
1.3 V
t_PLH
V_OH
V_OL
Out of phase output
1.3 V
V_OH
1.3 V
V_OL
Note: Input pulse; t_TLH ≤ 15 ns, t_THL ≤ 6 ns, PRR = 1 MHz, duty cycle 50%
Rev.2.00, Feb.18.2005, page 4 of 5