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FSTU3257
AC Electrical Characteristics
Note 7: This parameter is guaranteed by design but is not tested. The bus switch contributes no propagation delay other than the RC delay of the typical On
resistance of the switch and the 50pF load capacitance, when driven by an ideal voltage the source (zero output impedance).
Capacitance (Note 8)
Note 8: T
A
= +25°C, f = 1 MHz, Capacitance is characterized but not tested.
Undershoot Characteristic (Note 9)
Note 9: This is intended to characterize the device’s protective capabilities by maintaining output signal integrity during an input transient voltage undershoot
event.
FIGURE 1.
Device Test Conditions Transient
Input Voltage (V
IN
) Waveform
Symbol Parameter
T
A
= −40 °C to +85°C,
Units Conditions
C
L
= 50pF, RU = RD = 500Ω
Figure
V
CC
= 4.5 – 5.5V V
CC
= 4.0V
No.
Min Max Min Max
t
PHL
,t
PLH
Prop Delay Bus to Bus (Note 7) 0.25 0.25
ns V
I
= OPEN
Figures
2, 3
Prop Delay, Select to Bus A 7.0 30.0 35.0
t
PZH
, t
PZL
Output Enable Time, Select to Bus B 7.0 30.0 35.0
ns
V
I
= 7V for t
PZL
Figures
2, 3
Output Enable Time, OE to Bus A, B 7.0 30.0 35.0 V
I
= OPEN for t
PZH
t
PHZ
, t
PLZ
Output Disable Time, Select to Bus B 1.5 8.4 9.8
ns
V
I
= 7V for t
PLZ
Figures
2, 3
Output Disable Time, Output Enable Time, OE
to Bus A, B 1.5 8.8 9.8 V
I
= OPEN for t
PHZ
Symbol Parameter Typ Max Units Conditions
C
IN
Control Pin Input Capacitance 3 pF V
CC
= 5.0V
C
I/O
A Port
Input/Output Capacitance
7.5 pF
V
CC
, OE = 5.0V
B Port 5.5 pF
C
I/O
ON State Input/Output Capacitance ON State (A or B Port) 14 pF V
CC
= 5.0V Switch ON
Symbol Parameter Min Typ Max Units Conditions
V
OUTU
Output Voltage During Undershoot 2.5 V
OH
− 0.3 V Figure 1
Parameter Value Units
V
IN
See Waveform V
R
1
- R
2
100K Ω
V
TRI
11.0 V
V
CC
5.5 V
