LTC1759CG Linear Technology, LTC1759CG Datasheet
LTC1759CG
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LTC1759CG Summary of contents
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... AC adapter is programmable to avoid overloading the adapter when simultaneously supplying load current and charging cur- rent. When supplying system load current, charging cur- rent is automatically reduced to prevent adapter overload. , LTC and LT are registered trademarks of Linear Technology Corporation. 15.8k 1k 0.033 LTC1759 ...
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... UV V 0.4V, All Connected Pins UV Charging 5.5V, Shorted Thermistor DD Not Charging 5.5V DD 2.465V V V BAT2 MAX R Tolerance = 1% SET U W INFORMATION TOP VIEW ORDER PART NUMBER 36 PGND 35 BGATE 34 GBIAS LTC1759CG 33 BOOSTC BAT1 30 SPIN 29 SENSE 28 PROG SET 25 V LIMIT 24 I LIMIT 23 BAT2 22 DCIN ...
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ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range ( DCIN = 18V 12.6V BAT1, 2 PARAMETER BOOST Pin Current V Threshold to Turn T ...
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LTC1759 ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range ( DCIN = 18V 12.6V BAT1, 2 PARAMETER Thermistor Decoder (Note 11) Combined Input Leakage ...
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ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range ( DCIN = 18V 12.6V BAT1, 2 PARAMETER Charger Timing Rise/Fall Time TGATE ...
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LTC1759 W U TYPICAL PERFOR A CE CHARACTERISTICS Charger Efficiency 100 16.8V 95 12. 20V IN 70 0.5 1.5 2.5 3.5 CHARGING CURRENT (A) 1759 G09 Current from Battery vs Battery Voltage (Does Not ...
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PIN FUNCTIONS Input Power-Related Pins UV (Pin 7): Charger Section Undervoltage Lockout Pin. The rising threshold is 6.7V with a hysteresis of 0.5V. Switching stops in undervoltage lockout. Connect this input to the input voltage source with ...
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LTC1759 PIN FUNCTIONS V (Pin 27): This is the control signal of the inner loop of C the current mode PWM. Switching starts at 0.9V. Higher V corresponds to higher charging current in normal C operation. A ...
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W BLOCK DIAGRA BAT1 – – SDB 5 + 1.3V ONE SYNC 4 SHOT AGND 92mV + CLP + 9 CL1 CLN – 10 COMP1 11 INTB 13 ...
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LTC1759 TEST CIRCUITS V C 75k 0.047 0.65V 10 Test Circuit 1 LTC1759 – CA2 REF PROG 300 SET + LT1006 – 20k Test Circuit 2 LTC1759 + VA – V ...
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U OPERATIO Overview (Refer to Block Diagram and Figure 10) The LTC1759 is composed of a battery charger section, a charger controller, two 10-bit DACs to control charger parameters, a thermistor decoder, limit decoder and an SMBus controller block. If ...
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LTC1759 U OPERATIO Table 1: Supported Charger Functions SMBus ADDRESS FUNCTION (7-BIT) ChargerSpecInfo() b0001_001 ChargerMode() b0001_001 ChargerStatus() b0001_001 ChargingCurrent() b0001_001 ChargingVoltage() b0001_001 AlarmWarning() b0001_001 LTCVersionFunction() b0001_001 OptionalMfgFunction3() b0001_001 OptionalMfgFunction2() b0001_001 OptionalMfgFunction1() b0001_001 1 Alert Response Address b0001_100 1 Read-byte format. ...
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U OPERATIO FUNCTION FIELD RESET_TO_ZERO Reserved ChargerStatus() CHARGE_INHIBITED MASTER_MODE VOLTAGE_NOTREG CURRENT_NOTREG LEVEL_3:LEVEL_2 CURRENT_OR VOLTAGE_OR THERM_OR THERM_COLD THERM_HOT POWER-ON WORD BIT RESET VALUE MAPPING (BINARY) ALLOWED VALUES 3 0 • 0 – Charging Value Unchanged • 1 – Set Charging Values ...
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LTC1759 U OPERATIO FUNCTION FIELD THERM_UR ALARM_INHIBITED POWER_FAIL BATTERY_PRESENT AC_PRESENT ChargingCurrent() CHARGING_CURRENT [15:0] ChargingVoltage() CHARGING_VOLTAGE [15:0] AlarmWarning() OVER_CHARGED_ ALARM TERMINATE_CHARGE_ ALARM RESERVED_ALARM1 OVER_TEMP_ALARM 14 POWER-ON WORD BIT RESET VALUE ALLOWED VALUES MAPPING (BINARY) 11 Value • 0 – Thermistor Indicates ...
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U OPERATIO FUNCTION FIELD TERMINATE_ DISCHARGE_ALARM Reserved REMAINING_ CAPACITY_ALARM REMAINING_TIME_ ALARM INITIALIZED DISCHARGING FULLY_CHARGED FULLY_DISHARGED ERROR LTCVersionFunction LTC_VERSION () SMBus Accelerator Pull-Ups Both SCL and SDA have SMBus accelerator circuits which reduce the rise time on systems with significant capaci- ...
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LTC1759 U OPERATIO The Charger Controller Block The LTC1759 charger operations are handled by the charger controller block. This block is capable of charging the selected battery autonomously or under host control. The charger controller can request communications with the ...
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U OPERATIO Table 3. Charger_Controller Functional Features # CONDITION 0 POWER_ON_RESET = 1 1 CHARGING_RESET_STATE = 1 AND the Battery Is Present AND AC_PRESENT = 1 AND INHIBIT_CHARGE = 0 AND Thermistor Is Ideal 2 CHARGING_RESET_STATE = 1 AND the ...
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LTC1759 U OPERATIO # CONDITION 12 CHARGING_CONTROLLED_STATE = 1 AND THERM_HOT Changes from AND THERM_UR = 0 13 CHARGING_CONTROLLED_STATE = 1 AND THERM_UR Changes from AND THERM_HOT = 1 14 CHARGING_CONTROLLED_STATE = 1 AND ...
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U OPERATIO The Thermistor Decoder Block This block measures the resistance of the battery’s ther- mistor and features high noise immunity at critical trip points. The low power standby mode supports all SMB charger reporting requirements when AC is not ...
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LTC1759 U OPERATIO When AC power is not available the thermistor block supports the following low power operating features: 1. Only the low power THERM_OR detection circuitry is kept alive to support battery present interrupts. 2. The ChargeStatus() read function ...
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U OPERATIO Table 7. V Trip Points and Ranges LIMIT NOMINAL EXTERNAL CHARGING RESISTOR VOLTAGE ( VOLTAGE RANGE VLIMIT LIMIT 0 V < 0.09V 2465mV < V VLIMIT VCCP < 8432mV 10k 1% 0.17V < V 2465mV ...
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LTC1759 U OPERATIO When wake-up is asserted to the current DAC block, the delta-sigma is then fixed at a value equal to 80mA, inde- pendent of the I setting. LIMIT Note: The external resistor connected to the I multiplied by ...
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U U APPLICATIONS INFORMATION Charge Termination Issues Batteries with constant current charging and voltage- based charger termination might experience problems with reductions of charger current caused by adapter limiting recommended that input limiting feature be defeated in such ...
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LTC1759 U U APPLICATIONS INFORMATION Step 1: Determine R . Using your chosen I SENSE your maximum charge current, calculate the sense resis- tor value and round to the nearest standard value. Any rounding error is made up by the ...
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U U APPLICATIONS INFORMATION voltage will be pulled down by the constant 30W load until it reaches a lower stable state where the switching regu- lators can no longer supply full load. This situation can be prevented by utilizing the ...
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LTC1759 U U APPLICATIONS INFORMATION below ground with the full battery potential, causing a potential for latch-up in any of the devices connected to the SMBus inputs. Therefore it is good design practice to protect the SMBus inputs as shown ...
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... R6 3.3V = 330k 5V = 680k Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights crude voltage level detector looking for voltage going below approximately one volt on the emitter ...
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... High Efficiency Constant-Current/Constant-Voltage Charger LT1511 Monolithic 3A Constant-Current/Constant-Voltage Charger LTC1694 SMBus Accelerator in SOT-23 Package LT1769 Monolithic 2A Constant-Current/Constant-Voltage Charger PowerPath is a trademark of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com 4A SMBus Smart Battery Charger ...