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________________General Desc ription
The MAX1661/MAX1662/MAX1663 serial-to-parallel/
parallel-to-serial converters are intended to control external
power MOSFETs in power-plane switching applications.
These small, low-cost devices can be used on a system
motherboard to control point-of-load switching from a 2-
wire SMBus serial interface. Each device has three high-
voltage open-drain outputs that double as TTL-level logic
inputs, giving them bidirectional capabilities. The I/O pins
can withstand +28V, so they can control battery voltage-
distribution switches in notebook computers.
The MAX1661 is intended for driving N-channel MOSFETs
and its outputs are low upon power-up. The MAX1662/
MAX1663 are intended for P-channel MOSFETs, and their
outputs are high-impedance upon power-up. This ensures
that the MOSFETs are off at power-up, so the system can
enforce power-plane sequencing.
The
SMBSUS
control input selects control data between
two separate data registers. This feature allows the system
to select between two different power-plane configurations
asynchronously, eliminating latencies introduced by the
serial bus. Other features include thermal-overload and
overcurrent protection, ultra-low supply current, and both
hardware and software interrupt capabilities. These
devices are available in the space-saving 10-pin μMAX
package.
________________________Applic ations
Power-Plane Switching
Point-of-Load Power-Bus Switching
Notebook and Subnotebook Computers
Desktop Computers
Smart Batteries
____________________________Features
o
Performs Serial-to-Parallel and Parallel-to-Serial
Conversions
o
Three General-Purpose Digital Input/Output Pins
(withstand +28V)
o
SMBus 2-Wire Serial Interface
o
Supports
SMBSUS
Asynchronous Suspend Mode
o
3μA Supply Current
o
+2.7V to +5.5V Supply Range
o
Space-Saving, Low-Cost 10-Pin μMAX Package
M
________________________________________________________________ Maxim Integrated Products
1
1
2
3
4
5
10
9
8
7
6
ALERT
SMBCLK
SMBDATA
SMBSUS
I/O3
I/O2
I/O1
V
CC
MAX1661
MAX1662
MAX1663
μ
MAX
TOP VIEW
ADD
GND
__________________Pin Configuration
19-1306; Rev 0; 10/97
PART
MAX1661
EUB
MAX1662
EUB
MAX1663
EUB
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
TEMP. RANGE
PIN-PACKAGE
10 μMAX
10 μMAX
10 μMAX
EVALUATION KIT
AVAILABLE
Serial-to-Parallel/Parallel-to-Serial Converters and
Load-Switch Controllers with SMBus Interface
______________Ordering Information
Typical Operating Circuits appear at end of data sheet.
SMBus is a trademark of Intel Corp.
PART
POWER-ON-
RESET STATE
INTENDED
APPLICATION
SMBus ADDRESS
ADDRESS PIN
GND
High-Z
V
CC
GND
High-Z
V
CC
GND
High-Z
V
CC
ADDRESS
0100000
0111100
1001000
MAX1661
Outputs Low
N-Channel MOSFETs
MAX1662
Outputs High
(high-Z state)
P-Channel MOSFETs
0100001
0111101
1001001
MAX1663
Outputs High
(high-Z state)
P-Channel MOSFETs
0100010
0111110
1001010
______________________________________________________________S elec tor Guide