19-1306; Rev 0; 10/97
EVALUATION KIT
AVAILABLE
Serial-to-Parallel/Parallel-to-Serial Converters and
Load-Switch Controllers with SMBus Interface
________________General Description
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鈩?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 碌MAX
package.
____________________________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
3碌A Supply Current
o
+2.7V to +5.5V Supply Range
o
Space-Saving, Low-Cost 10-Pin 碌MAX Package
MAX1661/MAX1662/MAX1663
______________Ordering Information
PART
MAX1661EUB
MAX1662EUB
MAX1663EUB
TEMP. RANGE
-40掳C to +85掳C
-40掳C to +85掳C
-40掳C to +85掳C
PIN-PACKAGE
10 碌MAX
10 碌MAX
10 碌MAX
__________________Pin Configuration
TOP VIEW
V
CC
1
I/O1
2
3
4
5
10
ALERT
9
SMBCLK
SMBDATA
SMBSUS
ADD
________________________Applications
Power-Plane Switching
Point-of-Load Power-Bus Switching
Notebook and Subnotebook Computers
Desktop Computers
Smart Batteries
I/O2
I/O3
GND
MAX1661
MAX1662
MAX1663
8
7
6
碌MAX
Typical Operating Circuits appear at end of data sheet.
______________________________________________________________Selector Guide
PART
x
MAX1661
POWER-ON-
RESET STATE
Outputs Low
INTENDED
APPLICATION
N-Channel MOSFETs
SMBus ADDRESS
ADDRESS PIN
GND
High-Z
V
CC
GND
High-Z
V
CC
GND
High-Z
V
CC
ADDRESS
0100000
0111100
1001000
0100001
0111101
1001001
0100010
0111110
1001010
MAX1662
Outputs High
(high-Z state)
Outputs High
(high-Z state)
P-Channel MOSFETs
MAX1663
P-Channel MOSFETs
SMBus is a trademark of Intel Corp.
________________________________________________________________
Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 408-737-7600 ext. 3468.