SMM153
10-bit Digital Differential Voltage and Current Monitor
FEATURES & APPLICATIONS
•
Real-time power monitoring for “Green” systems
•
Differential Voltage Sensing of the DC-DC converter
output voltage
•
Supply-side current monitoring (10-bit ADC)
2
•
10-bit ADC readout of supply voltage over I C bus
•
Two programmable general purpose sensor inputs
(COMP1/2) – UV/OV with FAULT Output
•
Programmable glitch filters (COMP1/2)
•
Programmable internal COMP1/2 VREF: 0.5V or 1.25V
•
Operates from 2.7V to 5.5V supply
•
Current sensing from 4.0V to 15V supply
•
Programmable general-purpose inputs/outputs
•
General-purpose 256-Byte EEPROM with Write Protect
2
•
I C 2-wire serial bus for programming configuration and
monitoring status
•
28-lead 5x5 QFN package
INTRODUCTION
The SMM153 is a highly accurate power supply
voltage/current supervisor and monitor that allows real-
time power measurement for power-critical designs. The
part includes an internal voltage reference to accurately
monitor the supply to within ±1%. The SMM153 can read
the differential voltage of the supply and voltage drop of
the current sense resistor over the I
2
C bus using an on-
chip 10-bit ADC.
Two general purpose analog input pins are provided for
sensing under- or over-voltage conditions. A
programmable glitch filter associated with these inputs
allows the user to ignore spurious noise signals. A
FAULT# pin is asserted once either input set point is
exceeded. The
SMM153
also provides
four
programmable general-purpose inputs/outputs.
Using the I
2
C interface, a host system can communicate
with the SMM153 status register and utilize 256-bytes of
nonvolatile memory. The SMM153 operates from +2.7V
to +5.5V, however it can sense input current from an
input supply of +4.0V to +15V. The device is offered in
both commercial and industrial temperature ranges and
the package is a space-saving 5x5 QFN-28 one.
•
•
•
Applications
In-system test and control of Point-of-Load (POL)
Power Supplies for Multi-voltage Processors, DSPs
and ASICs
Routers, Servers, Storage Area Networks
TYPICAL APPLICATION
12VIN
2.7V-5.5V
R
S
CAPC
CS-
CS+
VDD
GND
VDD_CAP
COMP1
V1
Status
Output
COMP2
FAULT#
VREF
SDA
VIN
VOUT+
SEN+
I
2
C
Interface
SCL
A0-A2
WP
GPIO0
GPIO1
GPIO2
GPIO3
SMM153
CAPM+
VOUT-
SEN-
DC-DC Converter
CAPM-
VM+
VM-
Figure 1 – Application with the SMM153 used to Monitor a DC/DC Converter.
Notes: R
S
must be Kelvin sensed for maximum current sensing accuracy. This is an applications example only. Some components and values
are not shown.
© SUMMIT
Microelectronics, Inc. 2007 • 757 N. Mary Avenue • Sunnyvale CA 94085 • Phone 408 523-1000 • FAX 408 523-1266
http://www.summitmicro.com/
2134 3.0 1/20/2010
1
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
