DS2746 Datasheet, PDF (1/17 Pages) Vishay Siliconix – Low-Cost 2-Wire Battery Monitor with Ratiometric A/D Inputs

19-4632; 5/09
www.maxim-ic.com
GENERAL DESCRIPTION
The DS2746 provides system-side battery capacity
monitoring in cost-sensitive applications. Voltage,
bidirectional current, and accumulated current
measurement data is provided to the host processor
over a 2-wire interface. Offset bias and offset
blanking features greatly enhance the accuracy of
the coulomb counter. In addition, the DS2746 has
two auxiliary A/D inputs to sample the pack
identification resistor, thermistor, or other voltage
source. The results are reported as a ratiometric
fraction of the supply voltage eliminating error related
to the supply. The DS2746 reduces the total power
consumption of the measurement circuit by enabling
the resistor dividers, through the V_OUT pin, only while
measurements are made. When the system is
inactive, a low power sleep mode reduces current
consumption while maintaining the coulomb count.
The tiny 3mm × 3mm TDFN package consumes only
9mm² of PCB space.
APPLICATIONS
2.5G/3G Wireless Handsets
PDA/Smartphones
Digital Still and Video Cameras
Handheld Computers and Terminals
TYPICAL OPERATING CIRCUIT
DS2746
Low-Cost 2-Wire Battery Monitor
with Ratiometric A/D Inputs
FEATURES
 14-Bit Bidirectional Current Measurement
- 6.25V LSB, ±51.2mV Dynamic Range
- 416.7A LSB, ±3.4A Range (R_SNS = 15m)
 Current Accumulation Register Resolution
- 6.25Vhr LSB, 409.6mVh Range
- 417Ahr LSB, 27.31Ah Range
 11-Bit Battery Voltage Measurement
- 2.44mV LSB, 0V to 4.5V Input Range
- ±10mV Accuracy at 3.6V Input
 Two 11-Bit Aux Input Voltage Measurements
- Ratiometric Inputs Eliminate Supply Error
- VOUT drives Dividers, Reduces Power
- ±8 LSB Accuracy
 Low Power Consumption:
- Active Current: 70A typical, 100A max
- Sleep Current: 1A typical, 3A max
ORDERING INFORMATION
PART
DS2746G+
DS2746G+T&R
TEMP RANGE
-20ºC to +70ºC
-20ºC to +70ºC
PIN-PACKAGE
10-Pin 3mm×3mm
TDFN
DS2746G+ in Tape-
and-Reel
+ Denotes lead(Pb)-free/RoHS-compliant package.
PIN CONFIGURATION
TOP VIEW
3mm × 3mm TDFN
Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata.
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