
SMM605
1
(See Last Page)
Six-Channel Supply Voltage Marginer and Active DC Output Controller (ADOC
TM
)
Preliminary Information
SUMMIT
Microelectronics, Inc. 2003
1717 Fox Drive San Jose CA 95131 Phone 408 436-9890 FAX 408 436-9897
www.summitmicro.com
2064 1.1 9/16/03
1
FEATURES & APPLICATIONS
Extremely accurate (±0.1% Typ.) Active
DC Output Control (ADOC
TM
)
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
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
) 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.
SIMPLIFIED APPLICATIONS DRAWING
TRIM
B
VM
B
TRIM_CAP
B
CAP
B
TRIM
A
VM
A
TRIM_CAP
A
CAP
A
SMM605
μ
P/
ASIC
V
R
R
M
3.3VIN (+2.7V to +5.5V Range)
RESET
READY
HEALTHY
1
12VIN (+6V to +14V Range)
2.5VIN
1.2VIN
12V
SDA
SCL
I
2
C
BUS
3.3V
A2
VREF_CNTL
VIN
TRIM
Vout
DC/DC
Converter A
VIN
TRIM
Vout
DC/DC
Converter B
External or
Internal
REFERENCE
DC/DC
Converter C, E
DC/DC
Converter D, F
2 of 6 DC-DC
Converters shown
S
POWER GOOD
VDD_CAP
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.