Datasheet
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Electrical Characteristics
(1)
Switching Characteristics
SN74CB3T3257
4-BIT 1-OF-2 FET MULTIPLEXER/DEMULTIPLEXER
2.5-V/3.3-V LOW-VOLTAGE BUS SWITCH WITH 5-V-TOLERANT LEVEL SHIFTER
SCDS149 – OCTOBER 2003 – REVISED MARCH 2005
over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP
(2)
MAX UNIT
V
IK
V
CC
= 3 V, I
I
= –18 mA –1.2 V
V
OH
See Figures 3 and 4
I
IN
Control inputs V
CC
= 3.6 V, V
IN
= 3.6 V to 5.5 V or GND ± 10 µ A
V
I
= V
CC
– 0.7 V to 5.5 V ± 20
V
CC
= 3.6 V,
I
I
Switch ON, V
I
= 0.7 V to V
CC
– 0.7 V –40 µ A
V
IN
= V
CC
or GND
V
I
= 0 to 0.7 V ± 5
I
OZ
(3)
V
CC
= 3.6 V, V
O
= 0 to 5.5 V, V
I
= 0, Switch OFF, V
IN
= V
CC
or GND ± 10 µ A
I
off
V
CC
= 0, V
O
= 0 to 5.5 V, V
I
= 0 10 µ A
V
I
= V
CC
or GND 20
V
CC
= 3.6 V, I
I/O
= 0,
I
CC
µ A
Switch ON or OFF, V
IN
= V
CC
or GND
V
I
= 5.5 V 20
∆ I
CC
(4)
Control inputs V
CC
= 3 V to 3.6 V, One input at V
CC
– 0.6 V, Other inputs at V
CC
or GND 300 µ A
C
in
Control inputs V
CC
= 3.3 V, V
IN
= V
CC
or GND 3 pF
A port 7
C
io(OFF)
V
CC
= 3.3 V, V
I/O
= 5.5 V, 3.3 V, or GND, Switch OFF, V
IN
= V
CC
or GND pF
B port 5
V
I/O
= 5.5 V or 3.3 V 6
A port
V
CC
= 3.3 V,
V
I/O
= GND 16
C
io(ON)
Switch ON, pF
V
I/O
= 5.5 V or 3.3 V 4
V
IN
= V
CC
or GND
B port
V
I/O
= GND 16
I
O
= 24 mA 5 8
V
CC
= 2.3 V, TYP at V
CC
= 2.5 V,
V
I
= 0
I
O
= 16 mA 5 8
r
on
(5)
Ω
I
O
= 64 mA 5 7
V
CC
= 3 V,
V
I
= 0
I
O
= 32 mA 5 7
(1) V
IN
and I
IN
refer to control inputs. V
I
, V
O
, I
I
, and I
O
refer to data pins.
(2) All typical values are at V
CC
= 3.3 V (unless otherwise noted), T
A
= 25 ° C.
(3) For I/O ports, the parameter I
OZ
includes the input leakage current.
(4) This is the increase in supply current for each input that is at the specified TTL voltage level, rather than V
CC
or GND.
(5) Measured by the voltage drop between A and B terminals at the indicated current through the switch. ON-state resistance is determined
by the lower of the voltages of the two (A or B) terminals.
over recommended operating free-air temperature range (unless otherwise noted) (see Figure 2 )
V
CC
= 2.5 V V
CC
= 3.3 V
FROM TO
± 0.2 V ± 0.3 V
PARAMETER UNIT
(INPUT) (OUTPUT)
MIN MAX MIN MAX
t
pd
(1)
A or B B or A 0.15 0.25 ns
t
pd(s)
S A 1 9.5 1 7 ns
S B 1 9 1 7.5
t
en
ns
OE A or B 1 9 1 7.5
S B 1 7 1 7.5
t
dis
ns
OE A or B 1 6 1 8
(1) The propagation delay is the calculated RC time constant of the typical ON-state resistance of the switch and the specified load
capacitance, when driven by an ideal voltage source (zero output impedance).
5