IDT54/74FCT157T/AT/CT/DT, IDT54/74FCT257T/AT/CT/DT- 2257T/AT/CT
FAST CMOS QUAD 2-INPUT MULTIPLEXER
MILITARY AND COMMERCIAL TEMPERATURE RANGES
TEST CIRCUITS AND WAVEFORMS
TEST CIRCUITS FOR ALL OUTPUTS
SWITCH POSITION
Test
Switch
VCC
7.0V
Open Drain
Disable Low
Closed
500
Ω
Ω
Enable Low
VOUT
VIN
Open
Pulse
Generator
All Other Tests
DEFINITIONS:
CL= Load capacitance: includes jig and probe capacitance.
D.U.T.
2537 lnk 11
50pF
500
T
R
RT = Termination resistance: should be equal to ZOUT of the Pulse
C
L
Generator.
2537 drw 04
SET-UP, HOLD AND RELEASE TIMES
PULSE WIDTH
3V
DATA
1.5V
0V
INPUT
LOW-HIGH-LOW
t
H
tSU
1.5V
PULSE
3V
1.5V
0V
TIMING
INPUT
ASYNCHRONOUS CONTROL
tW
t
REM
PRESET
CLEAR
ETC.
3V
1.5V
0V
HIGH-LOW-HIGH
PULSE
1.5V
SYNCHRONOUS CONTROL
PRESET
3V
2537 drw 06
1.5V
0V
CLEAR
tSU
t
H
CLOCK ENABLE
ETC.
2537 drw 05
PROPAGATION DELAY
ENABLE AND DISABLE TIMES
ENABLE
DISABLE
3V
1.5V
0V
3V
SAME PHASE
CONTROL
INPUT
1.5V
0V
INPUT TRANSITION
t
PLH
t
t
PHL
PHL
t
PZL
tPLZ
VOH
OUTPUT
3.5V
1.5V
3.5V
1.5V
OUTPUT
NORMALLY
LOW
SWITCH
CLOSED
VOL
t
PLH
0.3V
0.3V
VOL
3V
1.5V
0V
tPZH
tPHZ
OPPOSITE PHASE
INPUT TRANSITION
VOH
OUTPUT
NORMALLY
HIGH
SWITCH
OPEN
1.5V
0V
2537 drw 07
0V
2537 drw 08
NOTES:
1. Diagram shown for input Control Enable-LOW and input Control Disable-
HIGH
2. Pulse Generator for All Pulses: Rate ≤ 1.0MHz; tF ≤ 2.5ns; tR ≤ 2.5ns
6.6
6
IDT [ INTEGRATED DEVICE TECHNOLOGY ]
