lt3651-4.1 Linear Technology Corporation, lt3651-4.1 Datasheet
lt3651-4.1
Related parts for lt3651-4.1
lt3651-4.1 Summary of contents
Page 1
... The LT3651 is available in a 5mm × 6mm 36-pin QFN package. TO SYSTEM LOAD 22μ 1μF 6.5μH WÜRTH 744314650 1N5819 SENSE 24mΩ BAT + NTC 100μF BATTERY 365142 TA01a LT3651-4.1/LT3651-4.2 Efficiency, Power Loss 3.9 BAT LOSS ...
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... LT3651-4.1/LT3651-4.2 ABSOLUTE MAXIMUM RATINGS (Note 1) V .......................................................................... 40V IN CLN, CLP , SHDN, CHRG, FAULT, ACPR ............................... V CLP – CLN .............................................................±0.5V SW ...........................................................................40V SW – V ..................................................................4.5V IN BOOST ......................................... SW + 10V Up to 50V SENSE, BAT ............................................................ 10V SENSE-BAT ............................................. –0.5V to 0.5V TIMER, RNG/SS NTC, RT .............................. 2.5V LIM Operating Junction Temperature Range (Notes 2, 3) ................................................ –40 to 125°C Storage Temperature Range ....................... – ...
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... BOOST – 4V. IN CONDITIONS V Rising IN V Rising IN LT3651-4.1 LT3651-4.2 Threshold Voltage Relative to V BAT(FLT) LT3651-4.1 V Rising BAT LT3651-4.2 V Rising BAT Threshold Voltage Relative to V BAT(PRE) CC/CV Mode, Top Switch On Standby Mode Shutdown (SHDN = 0) V – ...
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... LT3651-4.1/LT3651-4.2 ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifications are 0.68μ 50k, CLP = CLN = V TIMER T PARAMETER TIMER Charge/Discharge Current TIMER Disable Threshold Full Charge Cycle Time-Out Precondition Timeout Timer Accuracy Switcher Operating Frequency Minimum SW On-Time, t ON(MIN) Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device ...
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... Input Current Limit Voltage Threshold vs Temperature 2.0 1.5 1.0 R OPEN ILIM 0 10k ILIM 0 –0.5 –1.0 –1.5 –2.0 –50 – 1.2 TEMPERATURE (°C) LT3651-4.1/LT3651-4.2 SENSE and BAT Pin Current vs BAT Voltage, V SENSE 150 LT3651-4.2 100 50 0 –50 –100 –150 –200 –250 –300 –350 100 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4 ...
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... LT3651-4.1/LT3651-4.2 TYPICAL PERFORMANCE CHARACTERISTICS C/10 Threshold (V –V ) SENSE BAT vs Temperature –50 – 100 TEMPERATURE (°C) 365142 G10 Switch Drive ( BST SW vs Temperature –50 – 100 TEMPERATURE (°C) 365142 G13 Oscillator Frequency vs Temperature 1 ...
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... A temperature fault causes this pin corresponds to pulled low. If the internal timer is used for termination, MAX a bad battery fault also causes this pin to be pulled low fault conditions exist, the FAULT pin remains high impedance. LT3651-4.1/LT3651-4.2 and discharged by the bottom side IN 365142fb 7 ...
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... LT3651-4.1/LT3651-4.2 PIN FUNCTIONS CHRG (Pin 26): Open-Collector Charger Status Output. This pin indicates the battery charging status. Typically a resistor pull-up is used on this pin. This status pin can be pulled up to voltages as high as V and can sink currents up to 10mA when enabled. CHRG is pulled low during a battery charging cycle ...
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... NTC A1 + – 1.36V 50μA A2 – + 0.29V NTC 1 + – 1.3V 46μ 4.1V FOR LT3651-4.1, 4.2V FOR LT3651-4.2 BAT(FLT 4.0V FOR LT3651-4.1, 4.1V FOR LT3651-4.2 BAT(FLT) RECHRG V : 2.85V FOR LT3651-4.1, 2.9V FOR LT3651-4.2 BAT(PRE) STANDBY UVLO – + 4.6V R LATCH S Q OSC 0.2V + – + – A14 A11 A10 + 125°C V – ...
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... LT3651-4.1/LT3651-4.2 OPERATION Overview The LT3651 is a complete Li-Ion battery charger, addressing wide input voltage (4.8V to 32V) and high currents (up to 4A). High charging efficiency is produced with a constant frequency, average current mode synchronous step-down switcher architecture. The charger includes the necessary circuitry to allow for ...
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... R corresponds to 95mV across R internally to 1V maximum. If the junction temperature of the die becomes excessive, A10 activates decreasing I This reduces on-chip power dissipation to safe levels but continues charging. LT3651-4.1/LT3651-4.2 is reduced, lowering the charge current thus resistor (R LIM . ...
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... LT3651-4.1/LT3651-4.2 APPLICATIONS INFORMATION OSC Frequency A precision resistor to ground sets the LT3651 switcher oscillator frequency permitting user adjustability OSC of the frequency value. Typically this frequency is in the 200kHz to 1MHz range. Power consideration may neces- sitate lower frequency operation especially if the charger is operated with very high voltages ...
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... If this specification is not in the data sheet of an inductor, consult the vendor to make sure the maximum volt-second product is not being exceeded by your design. The minimum required volt-second product is approximately: V BAT f OSC(MHz) R SENSE + 365142 F01 SENSE LT3651-4.1/LT3651-4 typically set within a range of MAX ⎛ BAT F BAT F • 1– ...
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... LT3651-4.1/LT3651-4.2 APPLICATIONS INFORMATION System Input Current Limit The LT3651 contains a PowerPath help manage supply load currents. The charger adjusts charger output current in response to a system load maintain a constant input supply load. If overall input supply current exceeds the programmed maximum value the charge current is diminished in an attempt to keep supply current constant ...
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... RNG/SS is also pulled to ground during bad battery and NTC fault conditions graceful recovery from these faults is possible. Figure 7. Using the RNG/SS Pin for Soft-Start LT3651-4.1/LT3651-4.2 LT3651 RNG/SS 10k LOGIC HIGH = HALF CURRENT ...
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... LT3651-4.1/LT3651-4.2 APPLICATIONS INFORMATION Status Pins The LT3651 reports charger status through two open- collector outputs, the CHRG and FAULT pins. These pins can accept voltages as high 10mA when enabled. The CHRG pin indicates that the charger is delivering cur- rent at greater than a C/10 rate, or one-tenth of the pro- grammed maximum charge current ...
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... During an NTC fault, charging is halted and both status pins are pulled low. If timer termination is enabled, the LT3651-4.1/LT3651-4.2 timer count is suspended and held until the fault condition is relieved. The RNG/SS pin is also pulled low during this ...
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... LT3651-4.1/LT3651-4.2 APPLICATIONS INFORMATION with ground is recommended. Make Kelvin connections to the battery and sense resistor. Keep high current paths and transients isolated from battery ground, to assure an accurate output voltage reference. Effective grounding is achieved by considering switched current in the ground plane, and careful compo- ...
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... BATTERY 100μF 365142 TA03a TO SYSTEM C IN LOAD 22μF 1μF 3.3μH 1N5819 R SENSE 24mΩ BAT BATTERY 100μF 365142 TA05a LT3651-4.1/LT3651-4.2 Maximum Charge Current (V) IN 365142 TA02b Maximum Charge Current ...
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... LT3651-4.1/LT3651-4.2 PACKAGE DESCRIPTION 5.50 0.05 4.10 0.05 3.50 REF 5.00 0.10 PIN 1 TOP MARK (SEE NOTE 6) 6.00 0.10 NOTE: 1. DRAWING IS NOT A JEDEC PACKAGE OUTLINE 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 20 UHE Package Variation: UHE36MA 36-Lead Plastic QFN (5mm × 6mm) (Reference LTC DWG # 05-08-1753 Rev A) 1.52 2.54 0.05 0.05 0.25 0.05 3.45 0.05 3.45 0.05 0.76 0.05 0.25 0.05 0.50 BSC 4.50 REF 5.10 0.05 6.50 0.05 RECOMMENDED SOLDER PAD LAYOUT APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED ...
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... IN B 03/11 Revised entire data sheet to add LT3651-4.1 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... LT3651-4.1/LT3651-4.2 TYPICAL APPLICATION 6.5V to 32V 4A Charger with 3-Hour Charge Timeout, 6.3A Input Current Limit, 10ms Soft-Start and Battery Temperature Monitoring V LOGIC TO CONTROLLER RELATED PARTS PART NUMBER DESCRIPTION LT1511 3A Constant Current/Constant Voltage Battery Charger LT1513 SEPIC Constant or Programmable Current/Constant Voltage Battery Charger LT3650 2A Monolithic Li-Ion Battery Charger LT3651-8 ...