SMM665B
Six-Channel Active DC Output Controller, Monitor, Marginer and Sequencer
FEATURES & APPLICATIONS
•
Extremely accurate (±0.1%) Active
DC Output Control (ADOC
TM
)
•
Undervoltage Lockout function (UVLO)
•
ADOC
TM
Automatically adjusts supply output
voltage level under all DC load conditions
•
Monitors, controls, sequences and margins up
to six supplies from 0.3V to 5.5V with 1.25V Vref
Wide Margin/ADOC range from 0.3V to VDD
•
Programmable Power-on/-off sequencing
•
Monitors internal temperature sensor
•
Operates from any intermediate bus supply
from 8V to 15V and from 2.7V to 5.5V
•
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
•
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/Control Distributed and POL Supplies
•
Multi-voltage Processors, DSPs, ASICs used in
Telecom, CompactPCI or server systems
Preliminary Information
1
(See Last Page)
INTRODUCTION
The SMM665B 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
device actively controls up to six DC/DC converters
that use 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 SMM665B 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 8V to 15V or
from 5.5V to as low as 2.7V. The part 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 monitor
channels and output the data via the I
2
C bus. A host
system can communicate with the SMM665B status
register, optionally control Power-on/off, margining and
utilize 4K-bits of nonvolatile memory.
SIMPLIFIED APPLICATIONS DRAWING
12VIN (+8V to +15V Range)
3.3VIN (+2.7V to +5.5V Range)
12VIN
VDD
CAP
A
TRIM_CAP
A
DC/DC
Converter C, E
VIN
DC/DC
Converter A
Vout
TRIM
ON/OFF
2 of 6 DC-DC
Converters shown
VM
A
CAP
B
DC/DC
Converter D, F
VIN
DC/DC
Converter B
Vout
TRIM
ON/OFF
12V
3.3V
SDA
I
2
C
BUS
SCL
A2
External
or
Internal
TEMP
SENSOR
Environ
mental
SENSOR
External or
Internal
REFERENCE
2.5VIN
TRIM
A
PUP
A
AIN1
SMM665B
AIN2
VREF_CNTL
VREF_ADC
HEALTHY
TRIM_CAP
B
µP/
ASIC
1.2VIN
TRIM
B
PUP
B
RST
MR
VM
B
HEALTHY
RESET
READY
Figure 1 – Applications Schematic using the SMM665B Controller to actively control the output levels of
up to six 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:
2089 1.1 10/20/04
1
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
