Datasheet

SN74S225
16 × 5 ASYNCHRONOUS FIRST-IN, FIRST-OUT MEMORY
WITH 3-STATE OUTPUTS
SDLS207B – SEPTEMBER 1976 – REVISED APRIL 1998
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
PARAMETER MEASUREMENT INFORMATION
t
PHZ
t
PLZ
0.3 V
t
PZL
t
PZH
LOAD CIRCUIT FOR 3-STATE OUTPUTS
From Output
Under Test
Test Point
R1 = 500 Ω
S1
C
L
(see Note A)
7 V
Open
1.3 V
1.3 V1.3 V
3.5 V
3.5 V
0.3 V
0.3 V
t
h
t
su
VOLTAGE WAVEFORMS
SET UP AND HOLD TIMES
Timing
Input
Data
Input
1.3 V 1.3 V
3.5 V
3.5 V
0.3 V
0.3 V
High-Level
Pulse
Low-Level
Pulse
VOLTAGE WAVEFORMS
PULSE DURATION
1.3 V1.3 V
1.3 V
1.3 V
3.5 V
0.3 V
Output
Control
Waveform 1
S1 Closed
(see Note B)
Waveform 2
S1 Open
(see Note B)
0 V
V
OH
V
OL
3.5 V
0.3 V
1.3 V
1.3 V
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES, 3-STATE OUTPUTS
R2 = 500 Ω
t
w
t
PZH
t
PZL
t
PHZ
t
PLZ
t
PLH
t
PHL
Open
Closed
Open
Closed
Open
Open
PARAMETER S1
t
en
t
dis
t
pd
t
PHL
t
PLH
t
PLH
t
PHL
Input
(see Note C)
Out-of-Phase
Output
1.3 V 1.3 V
1.3 V1.3 V
1.3 V 1.3 V
3.5 V
0.3 V
V
OL
V
OH
V
OH
V
OL
In-Phase
Output
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
NOTES: A. C
L
includes probe and jig capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. All input pulses are supplied by generators having the following characteristics: PRR ≤ 1 MHz, Z
o
= 50 Ω, t
r
≤ 2 ns, t
f
≤ 2 ns.
D. The outputs are measured one at a time with one transition per measurement.
Figure 1. Load Circuit and Voltage Waveforms