LT3652 LINER [Linear Technology], LT3652 Datasheet
LT3652
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LT3652 Summary of contents
Page 1
... The LT3652 employs an input voltage regulation loop, which reduces charge current if the input voltage falls below a programmed level, set with a resistor divider. When the LT3652 is powered by a solar panel, the input regulation loop is used to maintain the panel at peak output power. The LT3652 can be confi gured to terminate charging when charge current falls below 1/10 of the programmed maximum (C/10) ...
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... LT3652EDD#PBF LT3652EDD#TRPBF LT3652IDD#PBF LT3652IDD#TRPBF LT3652EMSE#PBF LT3652EMSE#TRPBF LT3652IMSE#PBF LT3652IMSE#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. ...
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... SENSE BAT Charging Terminated Charging Terminated 4.2V IN BAT SENSE SW Charging Terminated CV Operation (Note 5) V Rising NTC V Falling NTC % of threshold Impedance to ground V = 0.8V NTC Rising 10mA Load LT3652 = 3.3V 0.68μF. FB TIMER MIN TYP MAX UNITS 4.6 4.95 V 0.2 V 3.282 3 ...
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... Specifi cations over the –40°C to 125°C operating junction temperature range are assured by design, characterization, and correlation with statistical process controls. The LT3652IDD specifi cations are guaranteed over the full –40°C to 125°C operating junction temperature range. High junction temperatures degrade operating lifetimes. ...
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... G03 12 BAT(PRE BAT BAT(FLT –50 2 2.5 (V) 3652 G05 LT3652 T = 25°C, unless otherwise noted Standby Mode Current IN vs Temperature 100 125 100 – –25 TEMPERATURE (°C) 3652 G01a Switch Forward Drop (V – ...
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... LT3652 TYPICAL PERFORMANCE CHARACTERISTICS Maximum Charge Current (V – Temperature SENSE BAT 101 100.8 100.6 100.4 100.2 100.0 99.8 99.6 99.4 99.2 99.0 50 –50 – 100 TEMPERATURE (°C) 3652 G07 Maximum Charge Current (V – SENSE BAT 100 2.65 2.66 2.67 2.68 2.69 2.7 V IN_REG Charge Current, Effi ciency, and ...
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... Maximum charge current is reduced when this pin is below 2.7V. Connecting a resistor divider from V enables programming of minimum operational V This is typically used to program the peak power voltage for a solar panel. The LT3652 servos the maximum charge current required to maintain the programmed operational V voltage, through maintaining the voltage above 2 ...
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... LT3652 PIN FUNCTIONS NTC (Pin 8): Battery Temperature Monitor Pin. This pin is the input to the NTC (Negative Temperature Coeffi cient) thermistor temperature monitoring circuit. This function is enabled by connecting a 10kΩ 3380 NTC thermistor from the NTC pin to ground. The pin sources 50μA, and monitors the voltage across the 10kΩ ...
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... S Q OSC 1MHz + – – C-EA STANDBY + + – 0. × – + 0.1V 1V 0.15V V INT x2.25 2.7V STANDBY 1.2V 1.36V 50μA – 0.29V + 46μA LT3652 V IN_REG + – 2.7V 4.6V BOOST + – 35V + 10mΩ – 30mV SENSE R S BAT OFFSET V FB – V-EA + – + 2.3V SHDN – ...
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... The LT3652 employs an input voltage regulation loop, which reduces charge current if a monitored input volt- age falls below a programmed level. When the LT3652 is powered by a solar panel, the input regulation loop is used to maintain the panel at peak output power. ...
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... IC comes out of standby mode and a new charging cycle is initiated. V Input Supply IN The LT3652 is biased directly from the charger input supply through the V IN currents high-quality, low ESR decoupling capacitor is recommended to minimize voltage glitches ...
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... Input ripple voltages above 0.1V are not recommended. 10μF is typically adequate for most charger applica- tions. Charge Current Programming The LT3652 charger is configurable to charge at average currents as high as 2A. Maximum charge current is set by choosing an inductor sense resistor (R the desired maximum average current through that sense ...
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... Status Pins section desired to operate a system load from the LT3652 charger output when the battery is disconnected, additional bypass capacitance is required. In this type of application, excessive ripple and/or low amplitude oscillations can oc- cur without additional output bulk capacitance. For these applications, place a 100μ ...
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... BAT(FLT) BAT(FLT) IN(MAX) Rectifier Selection The rectifier diode from SW to GND LT3652 battery charger provides a current path for the inductor current when the main power switch is disabled. The rectifier is selected based upon forward voltage, reverse voltage, and maximum current. A Schottky diode is required, as low ...
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... BAT pin to the V Extra care should be taken during board assembly. Small amounts of board contamination can lead to significant shifts in output voltage. Appropriate post-assembly board LT3652 and R FB1 FB2 = 3.3/(V – 3.3) BAT(FLT ...
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... determination of the temperature coefficient for V typical panel straight forward. The LT3652 employs a feedback network to program the V input regulation voltage. Manipulation of the network IN makes for efficient implementation of various temperature compensation schemes for a maximum peak power track- pin ...
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... LM234 into the output feedback network. For example, a 6-cell lead acid battery has a float charge voltage that is commonly specified at 2.25V/cell at 25°C, or 13.5V, and a –3.3mV/°C per cell temperature coefficient LT3652 is similar to that 17.6V can be inserted into the equations to OC equal SET ...
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... Figure 10. Thermistor-Based Temperature Compensation Network Programs V Float Charge Voltage for 6-Cell Charger 50 60 3652 F09b = 4 × 10 FLOAT(1-CELL) (T) + 2.375 (with a 2.18V minimum), where BAT 6-CELL 196k LEAD-ACID BATTERY + 69k 198k 22k 3380 LT3652 69k 3652 F10a 14.8 14.6 14.4 14.2 14.0 THEORETICAL V FLOAT 13.8 13.6 13.4 13.2 PROGRAMMED V BAT(FLOAT) 13.0 12.8 – ...
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... OFF Normal Charging at C/10 or Greater ON ON NTC Fault (Pause) If the battery is removed from an LT3652 charger that is configured for C/10 termination, a sawtooth waveform of approximately 100mV appears at the charger output, due to cycling between termination and recharge events, This cycling results in pulsing at the CHRG output. An LED connected to this pin will exhibit a blinking pattern, indicating to the user that a battery is not present ...
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... As such, removing a bad battery resets the LT3652 new charge cycle is started by connecting another battery to the charger output. Battery Temperature Monitor and Fault ...
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... LT3652 will suspend charging and enter standby mode until the excessive temperature condition is relieved. Layout Considerations The LT3652 switch node has rise and fall times that are typically less than 10nS to maximize conversion efficiency. The switch node (Pin SW) trace should be kept as short as possible to minimize high frequency noise ...
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... FAULT NTC V TIMER FB 10μF 0.68μF R1 10k B = 3380 REMOVABLE 2-CELL Li-Ion PACK (8.3V FLOAT) 3652 TA02b Charger (3.6V Float) With C/10 Termination LT3652 1μF V IN_REG BOOST SHDN SENSE CHRG BAT FAULT NTC TIMER V FB 223k 3652 TA03 Loop Servos Maximum Charge D3 ...
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... Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1725 Rev A) 0.70 ±0.05 2.38 ±0.05 1.65 ±0.05 PACKAGE OUTLINE 0.45 BSC 2.25 REF R = 0.115 3.00 ±0.10 (4 SIDES) 0.75 ±0.05 0.00 – 0.05 BOTTOM VIEW—EXPOSED PAD LT3652 0.40 ± 0.10 TYP 7 12 2.38 ±0.10 1.65 ± 0.10 PIN 1 NOTCH R = 0.20 OR 0.25 × 45° CHAMFER 6 1 0.23 ± 0.05 0.45 BSC 2 ...
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... LT3652 PACKAGE DESCRIPTION 2.845 0.102 (.112 .004) 5.23 (.206) MIN 0.42 0.038 (.0165 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE DETAIL “A” 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. ...
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... Add MSOP-12 Package 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. LT3652 PAGE NUMBER 3652fb ...
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... LTC40012-2/ LTC4012-3 Battery Charger with PowerPath™ Control PowerPath is a trademark of Linear Technology Corporation. Linear Technology Corporation 26 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● LT3652 1μF 1N914 BZX84C6V2L V IN_REG BOOST SHDN SENSE CHRG BAT 910 309k ...