SN74CBT16800 Datasheet, PDF (1/5 Pages) Texas Instruments – 20-BIT FET BUS SWITCH WITH PRECHARGED OUTPUTS

D 5-Ω Switch Connection Between Two Ports
D TTL-Compatible Input Levels
D B-Port Outputs Are Precharged by Bias
Voltage to Minimize Signal Distortion
During Live Insertion
D Package Options Include Plastic Thin
Shrink Small-Outline (DGG) and Thin Very
Small-Outline (DGV) Packages
description
The SN74CBT16800 provides 20 bits of
high-speed TTL-compatible bus switching. The
low on-state resistance of the switch allows
connections to be made with minimal propagation
delay. The device also precharges the B port to a
user-selectable bias voltage (BIASV) to minimize
live-insertion noise.
The device is organized as dual 10-bit bus
switches with separate output-enable (OE)
inputs. It can be used as two 10-bit bus switches
or one 20-bit bus switch. When OE is low, the
associated 10-bit bus switch is on and port A is
connected to port B. When OE is high, the switch
is open, the high-impedance state exists between
the two ports, and port B is precharged to BIASV
through the equivalent of a 10-kΩ resistor.
To ensure the high-impedance state during power
up or power down, OE should be tied to V_CC
through a pullup resistor; the minimum value of
the resistor is determined by the current-sinking
capability of the driver.
The SN74CBT16800 is characterized for
operation from –40°C to 85°C.
FUNCTION TABLE
(each 10-bit bus switch)
INPUT
OE
FUNCTION
L
A port = B port
A port = Z
H
B port = BIASV
SN74CBT16800
20-BIT FET BUS SWITCH
WITH PRECHARGED OUTPUTS
SCDS090 – MAY 1999
DGG OR DGV PACKAGE
(TOP VIEW)
BIASV ₁
1A1 ₂
1A2 ₃
1A3 ₄
1A4 5
1A5 6
1A6 7
GND 8
1A7 9
1A8 10
1A9 11
1A10 12
2A1 13
2A2 14
V_CC 15
2A3 16
GND 17
2A4 18
2A5 19
2A6 20
2A7 21
2A8 22
2A9 23
2A10 24
48 ^1OE
47 ^2OE
46 ^1B1
45 ^1B2
44 ^1B3
43 1B4
42 1B5
41 GND
40 1B6
39 1B7
38 1B8
37 1B9
36 1B10
35 2B1
34 2B2
33 2B3
32 GND
31 2B4
30 2B5
29 2B6
28 2B7
27 2B8
26 2B9
25 2B10
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCT PREVIEW information concerns products in the formative or
design phase of development. Characteristic data and other
specifications are design goals. Texas Instruments reserves the right to
change or discontinue these products without notice.
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Copyright © 1999, Texas Instruments Incorporated
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