鈩?/div>
(Enhanced-Performance Implanted
CMOS) Submicron Process
Useful for Jumperless Configuration of PC
Motherboard
Inputs Accept Voltages to 5.5 V
MUX OUT Signals are 2.5-V Outputs
NON-MUXED OUT Signal is a 3.3-V Output
Minimum of 1000 Write Cycles
Minimum of 10 Years Data Retention
Package Options Include Plastic
Small-Outline (D), Shrink Small-Outline
(DB), and Thin Shrink Small-Outline (PW)
Packages
D, DB, OR PW PACKAGE
(TOP VIEW)
I
2
C SCL
I
2
C SDA
OVERRIDE
MUX IN A
MUX IN B
MUX IN C
MUX IN D
GND
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
CC
WP
NON-MUXED OUT
MUX SELECT
MUX OUT A
MUX OUT B
MUX OUT C
MUX OUT D
description
This 4-bit 1-of-2 multiplexer with I
2
C input interface is designed for 3-V to 3.6-V V
CC
operation.
The PCA8550 is designed to multiplex four bits of data from parallel inputs or from I
2
C input data stored in a
nonvolatile register. An additional bit of register output also is provided, which is latched to prevent changes in
the output value during the write cycle. The factory default for the contents of the register is all low. These stored
values can be read from, or written to, using the I
2
C bus. The ability to control writing to the register is provided
by the write protect (WP) input. The override (OVERRIDE) input forces all the register outputs to a low.
This device provides a fast-mode (400 kbit/s) or standard-mode (100 kbit/s) I
2
C serial interface for data input
and output. The implementation is as a slave. The device address is specified in the I
2
C interface definition table.
Both of the I
2
C Schmitt-trigger inputs (SCL and SDA) provide integrated pullup resistors and are 5-V tolerant.
The PCA8550 is characterized for operation from 0擄C to 70擄C.
FUNCTION TABLE
INPUTS
MUX SELECT
L
L
OVERRIDE
L
H
OUTPUTS
MUX OUT
L
Nonvolatile
register
MUX IN
NON-MUXED
OUT
L
Nonvolatile
register
Latched
NON-MUXED
OUT鈥?/div>
H
X
鈥?The latched NON-MUXED OUT state is the value present on the
NON-MUXED OUT output at the time the MUX SELECT input
transitions from the low to the high state.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
EPIC is a trademark of Texas Instruments Incorporated.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright
漏
1999, Texas Instruments Incorporated
POST OFFICE BOX 655303
鈥?/div>
DALLAS, TEXAS 75265
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