CMOS, Low-Voltage, 2-Wire
Serially-Controlled, Matrix Switches
a
ADG728/ADG729
FEATURES
2-Wire Serial Interface
FUNCTIONAL BLOCK DIAGRAMS
2.7 V to 5.5 V Single Supply
2.5 ⍀ On Resistance
ADG728
ADG729
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
S1
S1A
S4A
DA
DB
D
Small 16-Lead TSSOP Package
S1B
S4B
APPLICATIONS
S8
Data Acquisition Systems
Communication Systems
Relay Replacement
Audio and Video Switching
Automatic Test Equipment
INPUT SHIFT
REGISTER
INPUT SHIFT
REGISTER
RESET
SDA SCL A0 A1
SDA SCL A0 A1
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.
1. 2-Wire Serial Interface.
2. Single Supply Operation. The ADG728 and ADG729 are
fully specified and guaranteed with 3 V and 5 V supply rails.
3. Low On Resistance 2.5 Ω typical.
4. Any configuration of switches may be on at any one time.
5. Guaranteed Break-Before-Make Switching Action.
6. Small 16-Lead TSSOP Package.
The ADG728 and ADG729 utilize a 2-wire serial interface that
is compatible with the I2C™ 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
configurations; 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.
I2C is a trademark of Philips Corporation.
REV. 0
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