74F776 Datasheet, PDF (9/12 Pages) NXP Semiconductors – Pi-bus transceiver

Philips Semiconductors
Pi–bus transceiver
Product specification
74F776
AC WAVEFORMS (Continued)
OEA
V_M
V_M
OEA
V_M
V_M
t_PZH
t_PHZ
V_OH -0.3V
An
V_M
0V
SF00429
t_PZL
t_PLZ
An
V_M
V_OL +0.3V
SF00430
Waveform 3. 3-state output enable time to high level and output
disable time from high level
Waveform 4. 3-state output enable time to low level and output
disable time from low level
Notes to AC waveforms
For all waveforms, V_M = 1.5V.
The shaded areas indicate when the input is permitted to change for predictable output performance.
TEST CIRCUIT AND WAVEFORMS
SWITCH POSITION
TEST SWITCH
t_PLZ, t_PZL closed
V_CC
All other open
V_IN
V_OUT
R_L
PULSE
D.U.T.
GENERATOR
R_T
C_L R_L
Test circuit for 3–State outputs on A port
V_CC
7.0V
V_IN
PULSE
GENERATOR
V_OUT
R_U
D.U.T.
R_T
C_D
7.0V
90%
NEGATIVE
PULSE
t_w
V_M
10%
t_{THL (}t_f )
V_M
10%
t_{TLH (}t_r )
90%
AMP (V)
low V
POSITIVE
PULSE
10%
t_{TLH (}t_r )
90%
V_M
t_w
t_{THL (}t_f )
90%
V_M
AMP (V)
10%
low V
Input pulse definition
INPUT PULSE REQUIREMENTS
family
amplitude Low V ^VM rep. rate
t_w
t_TLH
A port 3.0V 0.0V 1.5V 1MHz 500ns 2.5ns
B port 2.0V
1.0V 1.0V 1MHz 500ns 4.0ns
t_THL
2.5ns
4.0ns
Test circuit for outputs on B port
DEFINITIONS:
R_L =
C_L =
R_U =
C_D =
R_T =
Load resistor; see AC electrical characteristics for value.
Load capacitance includes jig and probe capacitance; see AC electrical characteristics for value.
Pull up resistor; see AC electrical characteristics for value.
Load capacitance includes jig and probe capacitance; see AC electrical characteristics for value.
Termination resistance should be equal to Z_OUT of pulse generators.
SF00431
December 19, 1990
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