a
FEATURES
2-Wire Serial Interface
2.7 V to 5.5 V Single Supply
2.5 On Resistance
0.75 On-Resistance Flatness
100 pA Leakage Currents
Single 8-to-1 Matrix Switch ADG728
Dual 4-to-1 Matrix Switch ADG729
Power-On Reset
Small 16-Lead TSSOP Package
APPLICATIONS
Data Acquisition Systems
Communication Systems
Relay Replacement
Audio and Video Switching
Automatic Test Equipment
CMOS, Low-Voltage, 2-Wire
Serially-Controlled, Matrix Switches
ADG728/ADG729
FUNCTIONAL BLOCK DIAGRAMS
ADG728
S1
S1A
DA
S4A
D
S1B
DB
S8
INPUT SHIFT
REGISTER
RESET
SDA SCL A0
A1
SDA SCL A0
A1
S4B
INPUT SHIFT
REGISTER
ADG729
GENERAL DESCRIPTION
PRODUCT HIGHLIGHTS
The ADG728 and ADG729 are CMOS analog matrix switches
with a serially controlled 2-wire interface. The ADG728 is an
8-channel matrix switch, while the ADG729 is a dual 4-channel
matrix switch. On resistance is closely matched between switches
and very flat over the full signal range. These parts can operate
equally well as either multiplexers, demultiplexers or switch
arrays and the input signal range extends to the supplies.
The ADG728 and ADG729 utilize a 2-wire serial interface that
is compatible with the I
2
C鈩?interface standard. Both have two
external address pins (A0 and A1). This allows the 2 LSBs of
the 7-bit slave address to be set by the user. Four of each of the
devices can be connected to the one bus. The ADG728 also has
a
RESET
pin that should be tied high if not in use.
Each channel is controlled by one bit of an 8-bit word. This
means that these devices may be used in a number of different
con铿乬urations; all, any, or none of the channels may be on at
any one time.
On power-up of the device, all switches will be in the OFF con-
dition and the internal shift register will contain all zeros.
All channels exhibit break-before-make switching action pre-
venting momentary shorting when switching channels.
The ADG728 and ADG729 are available in 16-lead TSSOP
packages.
1. 2-Wire Serial Interface.
2. Single Supply Operation. The ADG728 and ADG729 are
fully speci铿乪d and guaranteed with 3 V and 5 V supply rails.
3. Low On Resistance 2.5
鈩?/div>
typical.
4. Any con铿乬uration of switches may be on at any one time.
5. Guaranteed Break-Before-Make Switching Action.
6. Small 16-Lead TSSOP Package.
I
2
C is a trademark of Philips Corporation.
REV. 0
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: //www.analog.com
Fax: 781/326-8703
漏 Analog Devices, Inc., 2000
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