LTC2942
Battery Gas Gauge
with Temperature,
Voltage Measurement
Fea T Descrip T
n
Indicates Accumulated Battery Charge and
The LTC 2942 measures battery charge state, battery
Discharge
voltage and chip temperature in handheld PC and portable
n
High Accuracy Analog Integration
product applications. Its operating range is perfectly suited
n
ADC Measures Battery Voltage and Temperature
for single-cell Li-Ion batteries. A precision coulomb counter
n
Integrated Temperature Sensor
integrates current through a sense resistor between the
n
High Side Sense
batterys positive terminal and the load or charger. Battery
n
1% Voltage and Charge Accuracy
voltage and on-chip temperature are measured with an
n
50mV Sense Voltage Range
internal 14-bit No Latency ADC. The three measured
2
n
SMBus/I C Interface
quantities (charge, voltage and temperature) are stored in
2
n
Configurable Alert Output/Charge Complete Input
internal registers accessible via the onboard SMBus/I C
n
2.7V to 5.5V Operating Range
interface.
n
Quiescent Current Less than 100A
The LTC2942 features programmable high and low thresh-
n
Small 6-Pin 2mm 3mm DFN package
olds for all three measured quantities. If a programmed
threshold is exceeded, the device communicates an alert
using either the SMBus alert protocol or by setting a flag
a T
in the internal status register.
n
Low Power Handheld Products
n The LTC2942 requires only a single low value sense resis-
Cellular Phones
n tor to set the measured current range.
MP3 Players
n
Cameras L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
No Latency , ThinSOT and Bat-Track are trademarks of Linear Technology Corporation.
n
GPS
All other trademarks are the property of their respective owners.
Typical a T
Total Charge Error vs
Differential Sense Voltage
2.0
V + = 3.6V
SENSE
1.5
CHARGER LOAD
1.0
0.1F
+
SENSE
0.5
LTC2942
R
SENSE
AL/CC 100m
2
I C/SMBus 0
SDA
SENSE
TO HOST
SCL
0.5
+
GND 1-CELL
Li-Ion
1.0
2942 TA01a
1.5
2.0
0.1 1 10 100
V (mV)
SENSE
2942 TA01b
2942fa
1
CHARGE ERROR (%)
ion pplica
ions pplica
ion uresLTC2942
a Te m aximum r a T p in c F T
(Notes 1, 2)
+
Supply Voltage (SENSE ) ............................. 0.3V to 6V
TOP VIEW
SCL, SDA, AL/CC ......................................... 0.3V to 6V
+
6
SENSE 1 SENSE
+
SENSE .................................. 0.3V to (V + 0.3V)
SENSE
7
GND 2 5 AL/CC
Operating Ambient Temperature Range
LTC2942C ................................................ 0C to 70C SCL 3 4 SDA
LTC2942I.............................................. 40C to 85C
DCB PACKAGE
Storage Temperature Range ................... 65C to 150C
6-LEAD (2mm 3mm) PLASTIC DFN
T = 150C, = 120C/W
JMAX JA
EXPOSED PAD (PIN 7), DO NOT CONNECT
o r Der i n F T
Lead Free Finish
TAPE AND REEL (MINI) TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC2942CDCB#TRMPBF LTC2942CDCB#TRPBF LDVN 6-Lead (2mm 3mm) Plastic DFN 0C to 70C
LTC2942IDCB#TRMPBF LTC2942IDCB#TRPBF LDVN 6-Lead (2mm 3mm) Plastic DFN 40C to 85C
TRM = 500 pieces. *Temperature grades are identified by a label on the shipping container.
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on lead based finish parts.
For more information on lead free part marking, go to: