LTC2943 Multicell Battery Gas Gauge with Temperature, Voltage and Current Measurement FEATURES DESCRIPTION n Measures Accumulated Battery Charge and Discharge The LTC 2943 measures battery charge state, battery volt- n 3.6V to 20V Operating Range for Multiple Cells age, battery current and its own temperature in portable Application product applications. The wide input voltage range allows n 14-Bit ADC Measures Voltage, Current and use with multicell batteries up to 20V. A precision coulomb Temperature counter integrates current through a sense resistor between n 1% Voltage, Current and Charge Accuracy the batterys positive terminal and the load or charger. n 50mV Sense Voltage Range Voltage, current and temperature are measured with an n High Side Sense internal 14-bit No Latency ADC. The measurements n General Purpose Measurements for Any Battery are stored in internal registers accessible via the onboard 2 Chemistry and Capacity I C/SMBus Interface. 2 n I C/SMBus Interface The LTC2943 features programmable high and low thresh- n Configurable Alert Output/Charge Complete Input olds for all four measured quantities. If a programmed n Quiescent Current Less Than 120A threshold is exceeded, the device communicates an alert n Small 8-Lead 3mm 3mm DFN Package using either the SMBus alert protocol or by setting a flag in the internal status register. The LTC2943 requires only APPLICATIONS a single low value sense resistor to set the measured n Power Tools current range. n Electric Bicycles L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n Portable Medical Equipment No Latency and PowerPath are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. n Video Cameras TYPICAL APPLICATION Total Charge Error vs Differential Sense Voltage 2.0 1A + V = 10V SENSE CHARGER LOAD 3.3V 1.5 1F 1.0 LTC2943 2k 2k 2k + 0.5 SENSE V DD ALCC R SENSE 0 50m P SDA SENSE 0.5 SCL + GND MULTICELL 1.0 LI-ION 1.5 2943 TA01a 2.0 0.1 1 10 100 V (mV) SENSE 2943 TA01b 2943fa 1 For more information www.linear.com/LTC2943 CHARGE ERROR (%)LTC2943 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Notes 1, 2) + Supply Voltage (SENSE ) ........................... 0.3V to 24V TOP VIEW SCL, SDA, ALCC Voltage .............................. 0.3V to 6V + + SENSE ...............(0.3V + V ) to (V + 0.3V) + SENSE SENSE SENSE 1 8 SENSE Operating Ambient Temperature Range GND 2 7 GND 9 LTC2943C ............................................... 0C to 70C GND 3 6 ALCC SCL SDA 4 5 LTC2943I ............................................40C to 85C Storage Temperature Range .................. 65C to 150C DD PACKAGE 8-LEAD (3mm 3mm) PLASTIC DFN T = 150C, = 100C/W JMAX JA EXPOSED PAD (PIN 9) PCB GND CONNECTION OPTIONAL ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC2943CDD PBF LTC2943CDD TRPBF LGCS 8-Lead (3mm 3mm) Plastic DFN 0C to 70C LTC2943IDD PBF LTC2943IDD TRPBF LGCS 8-Lead (3mm 3mm) Plastic DFN 40C to 85C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: