74ABT853 Datasheet, PDF (7/7 Pages) NXP Semiconductors – 8-bit transceiver with 9-bit parity checker/ generator and flag latch 3-State

Philips Semiconductors
8-bit transceiver with 9-bit parity checker/
generator and flag latch (3-State)
Product specification
74ABT853
TYPICAL PROPAGATION DELAYS VERSUS LOAD FOR OPEN COLLECTOR OUTPUTS
18
16
14
12
t_PLH
10
8
6
4
t_PHL
2
0
0
100
200
300
400
500
600
Load resistor (Ω)
NOTE:
When using Open-Collector parts, the value of the pull–up resistor greatly affects the value of the t_PLH. For example, changing the specified pull-up resistor value from
500Ω to 100Ω will improve the t_PLH over 300% with only a slight change in the t_PHL. However, if the value of the pull-up resistor is changed, the user must make certain
that the total I_OL current through the resistor and the total I_IL’s of the receivers does not exceed the I_OL maximum specification.
SA00241
TEST CIRCUIT AND WAVEFORM
V_CC
V_IN
V_OUT
R_X
PULSE
GENERATOR
D.U.T
R_T
C_L
R_L
Test Circuit for 3-State Outputs
SWITCH POSITION
TEST SWITCH
t_PLZ
t_PZL
All other
closed
closed
open
LOAD VALUES
OUTPUT R_X V_X
ERROR 100Ω V_CC
All other 500Ω 7.0V
90%
V_X
NEGATIVE
PULSE
POSITIVE
PULSE
10%
V_M
10%
t_W
V_M
10%
t_THL (t_F)
t_TLH (t_R)
90%
V_M
90%
V_M
t_W
V_M = 1.5V
Input Pulse Definition
90%
AMP (V)
0V
t_TLH (t_R)
t_THL (t_F)
AMP (V)
10%
0V
DEFINITIONS
R_L = Load resistor; see AC CHARACTERISTICS for value.
C_L = Load capacitance includes jig and probe capacitance;
see AC CHARACTERISTICS for value.
R_T = Termination resistance should be equal to Z_OUT of
pulse generators.
FAMILY
74ABT
INPUT PULSE REQUIREMENTS
Amplitude Rep. Rate
t_W
t_R
t_F
3.0V
1MHz
500ns 2.5ns 2.5ns
SA00242
1995 Sep 06
7