SMS66
Six-Channel Power Supply Supervisor and Cacsade Sequence Controller
FEATURES & APPLICATIONS
•
•
•
•
•
•
•
•
Very accurate monitor function – 5mV steps
Monitors and sequences up to six supplies
Programmable Power-on/-off sequencing
Monitors internal temperature sensor
Operates from 12V or 3.3V supply
Monitors 12V input and VDD
Monitors two general-purpose 10-bit ADC inputs
Programmable threshold limits (2 OV/2 UV) for
each monitored input
•
Programmable RESET, HEALTHY and FAULT
functions
•
4k-bit general purpose nonvolatile memory
•
I
2
C 2-wire serial bus for programming
configuration and monitoring status, including
10-bit ADC conversion results
Applications
•
Monitor and Sequence Distributed Power and
Point of Load Power Supplies
•
Multi-voltage Processors, DSPs, ASICs used in
Telecom, CompactPCI or server systems
Preliminary Information
1
(See Last Page)
INTRODUCTION
The SMS66 is a very accurate programmable power
supply supervisor that monitors and sequences. It
controls sequencing time and position of up to six
isolated or non-isolated distributed or POL DC/DC
converters. The monitor supervisory function has two
independent UV and OV settings for each supply and
can be set in 5mV steps. The SMS66 also sequences
the power supplies in any order using enable outputs
with programmable polarity.
The SMS66 monitors six power supply channels as
well as VDD, 12V input, two general-purpose analog
inputs and an internal temperature sensor using a 10-
bit ADC. The 10-bit ADC can measure the value on
any one of the input channels and output the
conversion data via the I
2
C bus.
Using the I
2
C interface, a host system can
communicate with the SMS66 status register,
optionally control Power-on/off, and utilize 4 K-bits of
nonvolatile memory.
SIMPLIFIED APPLICATIONS DRAWING
12VIN (+8V to +15V Range)
VDD (+2.7V to +5.5V Range)
12VIN
VDD
DC/DC
Converter A
VIN
Vout
2.5VIN
12V
3.3V
SDA
I
2
C
BUS
SCL
A2
PUP
A
External
or
Internal
TEMP
SENSOR
ON/OFF
AIN1
SMS66
VM
A
DC/DC
Converter F
VIN
Vout
µP/
DSP/
NPU/
FPGA
1.2VIN
External or
Internal
REFERENCE
VREF_OUT
VREF_ADC
HEALTHY
PUP
F
ON/OFF
RST
MR
VM
F
HEALTHY
RESET
DONE
Figure 1 – Applications Schematic using the SMS66 Controller to cascade sequence up to six DC/DC
Converters while also providing supervisory functions.
Note: This is an applications example only. Some pins, components and values are not shown.
© SUMMIT
Microelectronics, Inc. 2003 •
300 Orchard City Drive, #131 • Campbell CA 95006
• Phone 408 378-6461 • FAX 408 378-6596
2070 1.0 7/16/03
www.summitmicro.com
1
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
