Rainbow Electronics DS2745 - Manual

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FEATURES
16-Bit Bidirectional Current Measurement
1.56 mV LSB, ±51.2mV Dynamic Range
104 mA LSB, ±3.4A Dynamic Range (RSNS =
15m W)
Current Accumulation Register Resolution
6.25 mVhr LSB, ±204.8mVh Range
0.417mAhr LSB, ±13.65Ah Range
(R
SNS
= 15m W)
11-Bit Voltage Measurement
4.88mV LSB, 0V to 5V Input Range
11-Bit Temperature Measurement
0.125ºC Resolution, -20ºC to +70ºC
Industry Standard I
2 C* Interface
Low Power Consumption:
Active Current:
70
mA typical, 100mA max
Sleep Current:
1
mA typical, 3mA max
BLOCK DIAGRAM
VDD
VIN
SCL
SNS VSS
SDA
Sense
DS2745
Li+
Protector
Fuel Gauge
Algorithm
µP
PACK-
COMM
PACK+
PIN CONFIGURATION
DESCRIPTION
The DS2745 provides current-flow, voltage, and
temperature measurement data to support battery-
capacity monitoring in cost-sensitive applications. The
DS2745 can be mounted on either the host side or
pack side of the application. Current measurement
and coulomb counting is accomplished by monitoring
the voltage drop across an external sense resistor,
voltage measurement is accomplished through a
separate voltage-sense input, and temperature
measurement takes place on-chip. A standard I
2 C
interface with software programmable address gives
the controlling microprocessor access to all data and
status registers inside the DS2745. A low-power sleep
mode state conserves energy when the cell pack is in
storage.
APPLICATIONS
Cellular
GPS
PDAs
Handheld Products
Table 1.
ORDERING INFORMATION
PART MARKING PIN-PACKAGE
DS2745U+ 2745 mMAX package
DS2745U+/T&R 2745 DS2745U+ in Tape-and-Reel
+Denotes lead-free package.
*I
2 C is a trademark of Philips Corp. Purchase of I 2 C components from Maxim Integrated Products, Inc., or one of its sublicensed Associated
Companies, conveys a license under the Philips I 2 C Patent Rights to use these components in an I 2 C system, provided that the system
conforms to the I 2 C Standard Specification as defined by Philips.
DS2745
Low-Cost I 2 C Battery Monitor
www.maxim-ic.com
mMAX
SDA
VDD
VIN
CTG
VSS
SNS
PIO
SCL
6
8
7
5
3
1
2
4
See Table 1 for Ordering Information.