WS82C55A
Timing Waveforms (Continued)
A0-A1,
CS
A0-A1,
CS
tWA (8)
tRA (2)
tAW (7)
tAR (1)
tRR (3)
DATA
BUS
RD
tDW (10)
tWD (11)
(4) tRD
tDF (5)
DATA
BUS
WR
VALID
HIGH IMPEDANCE
tWW (9)
FIGURE 30. WRITE TIMING
FIGURE 31. READ TIMING
AC Test Circuit
AC Testing Input, Output Waveforms
V1
INPUT
OUTPUT
VIH + 0.4V
VOH
1.5V
1.5V
R1
OUTPUT FROM
DEVICE UNDER
TEST
VIL - 0.4V
VOL
TEST
POINT
AC Testing: All AC Parameters tested as per test circuits. Input RISE and
FALL times are driven at 1ns/V.
R2
C1
(SEE NOTE)
TEST CONDITION DEFINITION TABLE
TEST CONDITION
V1
R1
R2
C1
NOTE: Includes STRAY and JIG Capacitance
1
2
3
1.7V
523Ω
2kΩ
Open
1.7kΩ
Open
150pF
50pF
50pF
V
CC
1.5V
750Ω
Burn-In Circuits
DIP40L
WS82C55A-5
F6
F7
F8
1
2
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
F11
F12
F13
3
F9
F4
F3
F14
F2
4
5
F5
6
7
GND
F0
F15
F11
8
F1
F10
F6
9
F12
F13
F14
F15
F11
F12
10
11
12
13
14
15
16
17
18
19
20
F7
F8
F9
V
CC
F10
F6
F13
F14
F15
F11
F12
C1
F7
F8
F9
F10
NOTES:
1. V
= 5.5V ± 0.5V
CC
2. VIH = 4.5V ± 10%
3. VIL = -0.2V to 0.4V
4. GND = 0V
21