LTC2942 Linear Technology, LTC2942 Datasheet
LTC2942
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LTC2942 Summary of contents
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... SMBus alert protocol or by setting a fl the internal status register. The LTC2942 requires only a single low value sense resis- tor to set the measured current range. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. No Latency Δ ...
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... SCL, SDA, AL/CC ......................................... –0. – SENSE .................................. –0. Operating Ambient Temperature Range LTC2942C ................................................ 0°C to 70°C LTC2942I.............................................. –40°C to 85°C Storage Temperature Range ................... –65°C to 150°C ORDER INFORMATION Lead Free Finish TAPE AND REEL (MINI) TAPE AND REEL ...
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... A CONDITIONS (Note 8) (Note 6) Extrapolated from Measurements at 5.5V and 2.7V (Note 8) (Note 6) V ≥ 2.8V (Note 8) SENSE + I = 3mA SENSE + IN (Note 8) www.DataSheet4U.com LTC2942 MIN TYP MAX UNITS 366 1.3 l 1.3 ±1 ±10 l ±1 ±4 ...
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... LTC2942 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER t Minimum Data Hold Time Input HD,DATI(MIN) t Data Hold Time Output HD,DATO t Data Output Fall Time of Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime ...
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... V (V) SENSE 3 = 85° –40°C –1 –2 –3 4.5 5.0 5.5 6.0 – (V) 2942 G07 www.DataSheet4U.com LTC2942 Total Charge Error vs Temperature 1.00 0.75 0.50 0.25 0 –0.25 –0.50 –0. –1.00 –50 25 6.0 –25 0 5.5 TEMPERATURE (°C) 2942 G02 Voltage Measurement ADC Total Unadjusted Error 85° ...
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... Negative Current Sense Input. Connect – SENSE to the positive battery terminal side of the sense resistor. The voltage between SENSE remain within ±50mV in normal operation. SENSE the input for the ADC in voltage measurement mode. LTC2942 ACCUMULATED COULOMB COUNTER CHARGE REGISTER REF CLK ...
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... OPERATION Overview The LTC2942 is a battery gas gauge device designed for use with single Li-Ion cells and other battery types with a terminal voltage at 2.7V to 5.5V. It measures battery charge and discharge, battery voltage and chip temperature. A precision coulomb counter integrates current through a sense resistor between the battery’s positive terminal and the load or charger ...
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... C and SMBus. The 7-bit 2 hard-coded I C address of the LTC2942 is 1100100. The LTC2942 is a slave-only device. Therefore the serial clock line (SCL input only while the serial data line (SDA) is bidirectional. The device supports I and fast mode. For more details refer to the I section ...
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... As soon as one of the three measured quantities exceeds the programmed limits, the corresponding bit A[4], A[3], A[2] or A[1] in the status register is set. Bit A[5] is set if the LTC2942’s accumulated charge registers (ACR) overfl ows or underfl ows. In these cases, the ACR stays at FFFFh or 0000h and does not roll over. ...
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... To achieve the specifi ed precision of the coulomb counter, the differential voltage between SENSE stay within ±50mV. For differential input signals up to ±300mV the LTC2942 will remain functional but the preci- sion of the coulomb counter is not guaranteed. The required value of the external sense resistor, R ...
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... LSB . q LSB INTERNAL (registers C, D). As the LTC2942 does not know the actual battery status at power-up, the accumulated charge register (ACR) is set to mid-scale (7FFFh). If the host knows the status of the battery, the accumulated charge (C[7:0]D[7:0]) can be either programmed to the correct value via I ...
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... Threshold Registers ( For each of the measured quantities (battery charge, volt- age and temperature) the LTC2942 features a high and a low threshold registers. At power-up, the high thresholds are set to FFFFh while the low thresholds are set to 0000h. ...
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... Figure 5. Read Protocol The master begins a read operation with a START condition followed by the seven bit slave address 1100100 and the R/W bit set to zero, as shown in Figure 6. The LTC2942 ...
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... The master initiates the ARA procedure with a START con- dition and the special 7-bit ARA bus address (0001100) followed by the read bit ( the LTC2942 is asserting the AL/CC pin in alert mode, it acknowledges and responds by sending its 7-bit bus address (1100100) and a 1. While ...
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... DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE www.DataSheet4U.com LTC2942 0.40 0.10 TYP 4 6 PIN 1 NOTCH R0 ...
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... GND COMMENTS 2.7V to 5.5V Operation, 14-Bit Δ∑-ADC, Pin Compatible with LTC2941-1 2.7V to 5.5V Operation, Pin Compatible with LTC2942 2.7V to 5.5V Operation, Pin Compatible with LTC2942-1 2.7V to 8.5V Operation, 10-Pin MSOP Package Simple ThinSOT Charger, No Blocking Diode, No Sense Resistor Needed Standalone, 4.7V ≤ Blocking Diode or External Power FET Required, ≤1.5A Charge Current Standalone Charger with Programmable Timer ...