EMC1702 Datasheet, PDF (1/57 Pages) SMSC Corporation – High-Side Current-Sense and Dual 1°C Temperature Monitor

EMC1702
High-Side Current-Sense and Dual
1°C Temperature Monitor
PRODUCT FEATURES
Datasheet
General Description
The EMC1702 is a combination high-side current sensing
device with precision temperature measurement. It
measures the voltage developed across an external sense
resistor to represent the high-side current of a battery or
voltage regulator. It also measures the source voltage and
uses these measured values to present a proportional
power calculation. The EMC1702 contains additional bi-
directional peak detection circuitry to flag instantaneous
current spikes with programmable time duration and
magnitude threshold. Finally, the EMC1702 includes an
external diode channel for temperature measurement as
well as an internal diode for ambient temperature
measurements.
The temperature measurement includes advanced features
such as Resistance Error Correction (REC), Beta
Compensation (to support CPU diodes requiring the
BJT/transistor model including 45nm and 65nm
processors), and automatic diode type detection.
Both current sensing and temperature monitoring include
two tiers of protection: one that can be masked and causes
the ALERT pin to be asserted, and the other that cannot be
masked and causes the THERM pin to be asserted.
Applications
„ Notebook and Desktop Computers
„ Industrial
„ Power Management Systems
„ Embedded Applications
Features
„ High-side current sensor
— Bi-directional current measurement
— Measures source voltage and indicates power ratio
— 1% current measurement accuracy
— Integrated over 82ms to 2.6sec with 11-bit resolution
— 3V to 24V bus voltage range
„ Independent hardware set instantaneous current peak
detector
— Software controls to program time duration and
magnitude threshold
„ Power supply options
— Bus or separately powered for low voltage operation
„ Wide temperature operating range: -40°C to +85°C
„ One external temperature monitor
— 1°C accuracy (20°C < T_DIODE < 110°C) with 0.125°C
resolution
— Ideality factor setting
— Support for 45nm and 65nm CPU diodes requiring the
BJT/transistor model w/ beta compensation
— Determines external diode type and optimal settings
— Resistance Error Correction
„ Internal temperature monitor
— ±1°C accuracy (-5°C < T_A < 85°C)
„ ALERT and THERM outputs for temperature, voltage,
and out-of-current limit reporting
„ SMBus 2.0 interface
— Pin-selectable SMBus Address
— Block Read and Write
„ Available in a 12-pin 4mm x 4mm QFN RoHS Compliant
Package
Block Diagram
Peak
Detection
DP
External
Temp
Current Limits
DN
Diode
Analog
13 - 15 bit
Σ Δ ADC
Current Registers
Mux
Internal
Temp
Diode
Configuration
11 - 15 bit
Σ Δ ADC
Power Register
Voltage and
Temp Registers
Voltage and
Temp Limits
SMBus
Slave
Protocol
ADDR_SEL
SMCLK
SMDATA
ALERT
THERM
SMSC EMC1702
DATASHEET
Revision 1.2 (09-27-10)