SMM605
Six-Channel Supply Voltage Marginer and Active DC Output Controller (ADOC
TM
)
FEATURES & APPLICATIONS
•
Extremely accurate (±0.1% Typ.) Active
DC Output Control (ADOC
TM
)
Preliminary Information
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(See Last Page)
INTRODUCTION
The SMM605 actively controls the output voltage level
of up to six DC/DC converters that use a ‘Trim’ or
‘VADJ/FB’ pin to adjust the output. An Active DC
Output Control (ADOC
TM
) feature is used during
normal operation to maintain extremely accurate
settings of supply voltages and, during system test, to
control margining of the supplies using the industry
standard I
2
C 2-wire data bus commands.
Total
accuracy with a ±0.1% external reference is ±0.2%,
and ±0.5% using the internal reference. The device
can margin supplies with either positive or negative
trim pin control within a range of 0.35V to VDD. The
SMM605 supply can range from 2.7V to 5.5V or 6V to
14V to accommodate any intermediate bus supply.
The voltage settings (margin high/low and
nominal) are programmed into nonvolatile memory.
The I
2
C bus is used to enable margin high, margin low,
ADOC or normal operation. When margining, the
SMM605 will check the voltage output of the converter
and make adjustments to the trim pin via a feedback
loop to bring the voltage to the margin setting. A
margining status register is set to indicate that the
system is ready for test.
•
Six channel control of DC/DC converters
•
ADOC Automatically adjusts supply output
voltage level under all DC load conditions
•
Capable of margining supplies with trim inputs
using either positive or negative trim pin control
•
Wide Margin/ADOC range from 0.35V to VDD
•
Uses either an internal or external VREF
•
Operates from any intermediate bus supply
from 8V to 15V and from 2.7V to 5.5V
•
Programmable START and READY pins
•
General Purpose 4k EEPROM with Write Protect
•
I
2
C 2-wire serial bus for programming
configuration and monitoring status.
•
48 lead TQFP package
Applications
•
Monitor/Control Distributed and POL Supplies
•
Multi-voltage Processors, DSPs, ASICs used in
Telecom, CompactPCI or server systems
SIMPLIFIED APPLICATIONS DRAWING
12VIN (+6V to +14V 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
12V
3.3V
SDA
I
2
C
BUS
SCL
A2
VDD_CAP
2.5VIN
TRIM
A
2 of 6 DC-DC
Converters shown
VM
A
CAP
B
SMM605
DC/DC
Converter D, F
VIN
DC/DC
Converter B
Vout
TRIM
TRIM_CAP
B
µP/
ASIC
1.2VIN
External or
Internal
REFERENCE
VREF_CNTL
TRIM
B
START
READY
RST
MR
VM
B
HEALTHY
RESET
READY
POWER GOOD
Figure 1 – Applications Schematic using the SMM605 Controller to actively control and margin the output
levels of up to six DC/DC Converters.
Note: This is an applications example only. Some pins, components and values are not shown.
© SUMMIT
Microelectronics, Inc. 2003
• 1717 Fox Drive • San Jose CA 95131 • Phone 408 436-9890 • FAX 408 436-9897
2064 1.1 9/16/03
www.summitmicro.com
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