SMM151_10 Datasheet, PDF (1/24 Pages) Summit Microelectronics, Inc. – Single-channel Voltage/Current Monitors and Voltage Marginers

SMM151/152
Single-channel Voltage/Current Monitors and Voltage Marginers
FEATURES & APPLICATIONS
INTRODUCTION
• Capable of margining supplies with trim inputs using
either positive or negative trim pin control
• Wide Margin range of 0.3V to VDD with internal
reference
• Differential Voltage Sensing of the DC-DC converter
output voltage
• Supply-side current monitoring (10-bit ADC)
• 10-bit ADC readout of supply voltage over I²C bus
• Margining Controlled Via:
I²C Command
Input Pins (M_UP, M_DN)
• 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 I/Os (SMM152)
• General Purpose 256-Byte EEPROM with Write Protect
• I²C 2-wire serial bus for programming configuration and
monitoring status
• 28-lead 5x5 QFN
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
The SMM151/152 are highly accurate power supply
voltage/current supervisors and monitors with provisions for
voltage margining of the monitored supply. The parts include
an internal voltage reference to accurately monitor and margin
the supply to within ±1%. The SMM151/152 have the capability
to margin over a wide range from 0.3V to VDD using the
internal reference and can read the differential voltage of the
supply and voltage drop of the current sense resistor over the
I²C bus using an on-chip 10-bit ADC. The margin levels are set
using the I²C serial bus. The devices initiate margining via the
I²C bus or by using the M_UP or M_DN inputs. Once the pre-
programmed margin target voltage is reached, the
SMM151/152 hold the converter at this voltage until receiving
an I²C command or de-asserting the margin input pin. When
the SMM151/152 are not margining, the TRIM output pin is
held in a high impedance state allowing the converter to
operate at its nominal set point.
Two general purpose 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 SMM152 also provides four
programmable general-purpose inputs/outputs.
Using the I²C interface, a host system can communicate with
the SMM151/152 status register and utilize 256-bytes of
nonvolatile memory.
4.0V-15V
R_S
2.7V-5.5V
Margin
Commands
Status
Outputs
I²C
Interface
CAPC
CS-
CS+
MUP
MDN
FAULT#
READY
SDA
SCL
A0-A2
WP
(GPIO0)
(GPIO1)
(GPIO2)
(GPIO3)
VDD
GND VDD_CAP
COMP1
V1
SMM151
(SMM152)
COMP2
VREF
TRIM
CAPM+
CAPM-
VM+
VM-
VIN _VOUT+
SEN+
TRIM
VOUT-
SEN-
DC-DC Converter
Figure 1 – Application with the SMM151/152 used to Monitor and Margin 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 [phone] • FAX [phone]
http://www.summitmicro.com/
2131 3.0 1/20/2010
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