SMM766
Six-Channel Active DC Output Controller, Monitor, Marginer and Sequencer with Sequence-Link
Preliminary Information
1
(See Last Page)
FEATURES & APPLICATIONS
•
Extremely accurate (±0.2%) Active
DC Output Control (ADOC™)
•
Sequence-Link™ provides sequencing of up to
48 channels
•
ADOC automatically adjusts supply output
voltage level under all DC load conditions
•
Monitors, controls, and margins up to 6
supplies from 0.3V to 5.5V with 1.25V Vref
•
Programmable power-on/-off sequencing
•
Operates from any intermediate bus supply
from 6V to 14V and from 2.7V to 5.5V
•
Monitors 12V input VDD and temperature sensor
•
Wide margin/ADOC range from 0.3V to VDD
•
Monitors two general-purpose 10-bit ADC inputs
•
I
2
C 2-wire serial bus for programming
configuration and monitoring status, including
10-bit ADC conversion results
•
2 programmable Under Voltage (UV) and Over
Voltage (OV) threshold limits for each of 11
monitored inputs
•
2k-bit general purpose nonvolatile memory
Applications
•
Monitor/control distributed and POL supplies
•
Multi-voltage processors, DSPs, ASICSs used in
telecom, CompactPCI or server systems
INTRODUCTION
The SMM766 is an Active DC Output power supply
Controller (ADOC
TM
) that monitors, margins, and
cascade sequences. The ADOC feature is unique and
maintains extremely accurate settings of system
supply voltages to within ±0.2% under full load. The
SMM766 actively controls up to 6 DC/DC converters
and can be linked with up to 7 other Sequence-Link™
devices to accommodate sequencing of up to 48
channels. Control of the DC-DC converters is
accomplished through the use of a Trim or Regulator
VADJ/FB pin to adjust the output voltage. For system
test, the part also controls margining of the supplies
using I
2
C commands. It can margin supplies with
either positive or negative control within a range of
0.3V to VDD, depending on the specified range of the
converter. The SMM766 also intelligently sequences
or cascades the power supplies on and off in any
order using enable outputs with programmable
polarity. It can operate off any intermediate bus supply
ranging from 6V to 14V or from 5.5V to as low as 2.7V.
The part monitors 6 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 monitor channels and output the data via
the I
2
C bus. A host system can communicate with the
SMM766 status register, margining and utilize 2K-bits
of nonvolatile memory.
SIMPLIFIED APPLICATIONS DRAWING
12VIN (+6V to +14V Range)
3.3VIN (+2.7V to +5.5V Range)
12VIN
VDD
CAP
A
TRIM_CAP
A
SDA
SCL
A2
SEQ_LINK
External
or
Internal
TEMP
SENSOR
TRIM
A
PUP
A
VM
A
CAP
B
TRIM_CAP
B
AIN2
HEALTHY
VREF
MR#
2 of 6 DC-DC
Converters shown
DC/DC
Converter D, F
VIN
DC/DC
Converter B
Vout
TRIM
ON/OFF
12V
DC/DC
Converter C, E
VIN
DC/DC
Converter A
Vout
TRIM
ON/OFF
3.3V
To additional Sequence-
Link devices
I
2
C
BUS
2.5VIN
SMM766
AIN1
µP/
ASIC
1.2VIN
Environmental
SENSOR
External or
Internal
REFERENCE
TRIM
B
PUP
B
RST#
VM
B
HEALTHY
RESET#
READY
Figure 1 – Applications schematic using the SMM766 controller to actively control the output levels of up
to 6 DC/DC converters while also providing power-on/off, cascade sequencing and output margining.
Note: This is an applications example only. Some pins, components and values are not shown.
© SUMMIT
Microelectronics, Inc.
2004 • 1717 Fox Drive • San Jose CA 95131 • Phone 408 436-9890 • FAX 408 436-9897
The Summit Web Site can be accessed by “right” or “left” mouse clicking on the link:
http://www.summitmicro.com/
2086 2.1 12/13/2005
1
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
