ltc2941-1 Linear Technology Corporation, ltc2941-1 Datasheet
ltc2941-1
Related parts for ltc2941-1
ltc2941-1 Summary of contents
Page 1
... The measured charge is stored in internal registers. An SMBus/I terface accesses and configures the device. The LTC2941-1 features programmable high and low thresholds for accumulated charge threshold is ex- ceeded, the device communicates an alert using either the SMBus alert protocol or by setting a flag in the internal status register ...
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... SCL, SDA, AL/CC ......................................... –0. – Sense Current (into SENSE ) ....................................±2A Operating Ambient Temperature Range LTC2941-1C ............................................. 0°C to 70°C LTC2941-1I .......................................... –40°C to 85°C Storage Temperature Range ..................... –65°C to 150° orDer inFormaTion Lead Free Finish TAPE AND REEL (MINI) TAPE AND REEL ...
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... Note 8: Value decreases if exposed pad is soldered to large copper area. See Power Dissipation section for more information SU, STA HD, DATO HD, STA HD, DATI REPEATED START CONDITION 2 Figure 1. Definition of Timing Bus LTC2941-1 MIN TYP MAX 0.3 • V 0.7 • V SENSE + SENSE + l 0 ...
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... LTC2941-1 Typical perFormance characTerisTics Total Charge Error vs Sense Current 1.00 0.75 0.50 0.25 0 –0.25 –0.50 –0. 2.7V SENSE + V = 4.2V SENSE + –1. 100 1000 |I | (mA) SENSE 29411 G01 Supply Current vs Supply Voltage 100 T = 25° –40° 85° 2.5 3.0 3.5 4.0 4.5 5.0 5 (V) SENSE 29411 G04 ...
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... Negative Current Sense Input. Connect – SENSE to the positive battery terminal. Current from/into this pin must not exceed 1A in normal operation. Exposed Pad (Pin 7): Do Not Connect. Soldering the exposed pad to adequate electrically isolated copper area is recommended for best thermal performance. LTC2941-1 29411f ...
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... SUPPLY R BOND + 12m SENSE SENSE BOND 50m – 12m SENSE 6 GND 2 ACCUMULATED BIDIRECTIONAL PRESCALER INTEGRATOR M REF CLK INTERNAL INTERNAL REFERENCE OSCILLATOR GENERATOR Figure 2. Block Diagram of the LTC2941-1 CC CHARGE AL AL/CC REGISTER 5 2 SCL SMBus SDA STATUS/ 4 CONTROL REGISTER 29411 F02 29411f ...
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... Overview The LTC2941 battery gas gauge device designed for use with single Li-Ion cells and other battery types with terminal voltages from 2.7V to 5.5V. A precision coulomb counter integrates current through an internal sense resis- tor between the battery’s positive terminal and the load or charger ...
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... I C and SMBus. The 7-bit 2 hard-coded I C address of LTC2941-1 is 1100100. The LTC2941 slave-only device. Therefore, the serial clock line (SCL) is input only while the data line (SDA) is bidirectional. The device supports I mode. For more details refer to the I Internal Registers ...
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... SUPPLY Power Down B[0] Programming the last bit B[0] of the control register to 1 sets the analog parts of the LTC2941-1 in power down and the current consumption drops typically below 1µA. All analog circuits are disabled while the values in the registers are retained. Note that any charge flowing while B[ not measured and the charge information below 1LSB of the accumulated charge register is lost ...
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... B[ Threshold Registers (E, F), (G, H) alert function BAT For battery charge, the LTC2941-1 features a high and a low threshold register. At power-up the high threshold is set to FFFFh while the low threshold is set to 0000h. Both thresholds can be programmed to a desired value via I ...
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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 LTC2941-1 is as- serting the AL/CC pin in alert mode, it acknowledges and responds by sending its 7-bit bus address (1100100) and a 1 ...
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... SCL ADDRESS START CONDITION Figure 5. Writing FCh to LTC2941-1 Control Register (B) Figure 6. Writing F001h to the LTC2941-1 Accumulated Charge Registers ( ADDRESS 1100100 S ADDRESS 1100100 Figure 8. Reading the LTC2941-1 Accumulated Charge Registers (C, D) Figure 9. LTC2941-1 Serial Bus SDA Alert Response Protocol ...
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... Voltage Drop Between SENSE and SENSE The LTC2941-1 is trimmed for an effective internal resis- tance of 50mΩ , but the total pin-to-pin resistance (R consisting of the sense resistor in series with pin and bond wire resistances, is somewhat higher. Assuming a sense ...
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... Figure 10). Put the bypass capacitor close to SENSE copper area on exposed pad for heat sinking. TO CHARGER/LOAD and GND. Provide adequate ELECTRICALLY ISOLATED HEAT SINK TO BATTERY LTC2941 CONNECTED TO EXPOSED PAD ONLY 2941 F10 Figure 10. Recommended Layout 29411f ...
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... ALL DIMENSIONS ARE IN MILLIMETERS 4. 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 LTC2941-1 0.40 0.10 TYP 4 6 PIN 1 NOTCH R0 ...
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... GND COMMENTS Pin Compatible with LTC2942 14-Bit ∆∑ ADC, Pin Compatible with LTC2941 14-Bit ∆∑ ADC, Pin Compatible with LTC2941-1 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 ...