LTC4068-4.2 Linear Technology, LTC4068-4.2 Datasheet
LTC4068-4.2
Related parts for LTC4068-4.2
LTC4068-4.2 Summary of contents
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... TO 6.5V LTC4068-4.2 CHRG ITERM ACPR EN PROG GND 1µF LTC4068-4.2/LTC4068X-4.2 Li-Ion Battery Charger with Programmable Termination DESCRIPTIO ® The LTC 4068 is a complete constant-current/constant- voltage linear charger for single cell lithium-ion batteries. Its DFN package and low external component count make the LTC4068 ideally suited for portable applications. Fur- thermore, the LTC4068 is designed to work within USB power specifications ...
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... LTC4068-4.2/LTC4068X-4 ABSOLUTE AXI U RATI GS (Note 1) Input Supply Voltage (V ) ....................... –0.3V to 10V CC PROG, ITERM ................................ – 0. BAT ............................................................. –0. CHRG, ACPR, EN ...................................... –0.3V to 10V BAT Short-Circuit Duration .......................... Continuous BAT Pin Current ........................................................ 1A PROG Pin Current ................................................... 1mA Maximum Junction Temperature .......................... 125°C Operating Temperature Range (Note 2) .. – 40°C to 85°C Storage Temperature Range ................. – ...
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... 10k PROG 1.005 1.000 0.995 0.990 0.985 4 4.5 5 5.5 6 6.5 V (V) CC 405842 G01 LTC4068-4.2/LTC4068X-4.2 ● The denotes specifications which apply over the full operating = 25° 5V, unless otherwise noted CONDITIONS =1000V/R BAT BAT PROG V High to Low BAT I ...
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... LTC4068-4.2/LTC4068X-4 TYPICAL PERFOR A CE CHARACTERISTICS Regulated Output (Float) Voltage vs Charge Current 4. 25°C 4. 1.25k PROG 4.22 4.20 4.18 4.16 4.14 4.12 4.10 0 100 200 300 400 500 600 700 I (mA) BAT 405842 G04 CHRG Pin I-V Curve (Pull-Down State –40° 25° ...
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... TERM BAT (Pin 2): Charge Current Output. Provides charge current to the battery from the internal P-channel MOSFET, and regulates the final float voltage to 4.2V. An internal precision resistor divider from this pin sets the float LTC4068-4.2/LTC4068X-4.2 Charge Current vs Ambient Temperature 600 = 2k 500 ...
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... LTC4068-4.2/LTC4068X-4 CTIO S PROG (Pin 5): Charge Current Program and Charge Cur- rent Monitor. Charge current is programmed by connect- ing a 1% resistor ground. When charging in PROG constant-current mode, this pin servos to 1V. In all modes, the voltage on this pin can be used to measure the charge ...
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... V PROG I • 1000 = BAT R PROG LTC4068-4.2/LTC4068X-4.2 Programming Charge Termination The charge cycle terminates when the charge current falls below the programmed termination threshold. This threshold is set by connecting an external resistor, R from the ITERM pin to ground. The charge termination current threshold ( ...
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... LTC4068-4.2/LTC4068X-4.2 U OPERATIO threshold (V ), another charge cycle begins and RECHRG charge current is once again supplied to the battery. To manually restart a charge cycle when in standby mode, the input voltage must be removed and reapplied or the charger must be shut down and restarted using the EN pin. Figure 1 shows the state diagram of a typical charge cycle ...
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... LTC4068 will begin to reduce the charge current is approximately 120°C – (5V – 3.3V) • (800mA) • 50°C 120°C – 1.36W • 50°C/W = 120°C – 68° 52°C A www.DataSheet4U.com LTC4068-4.2 CHARGE 10k CURRENT PROG MONITOR CIRCUITRY R C PROG FILTER GND 406842 F02 – ...
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... The charge termination threshold remains fixed at 80mA. 5V WALL ADAPTER 800mA I CHG USB POWER 500mA I CHG Figure 3. Combining Wall Adapter and USB Power www.DataSheet4U.com I CHG LTC4068-4 BAT ITERM MP1 GND PROG 1 ...
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... 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. LTC4068-4.2/LTC4068X-4 Figure 4. Low Loss Input Reverse Polarity Protection ...
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... Port, Keeps Current Drawn from USB Port Constant, Keeps Battery Fresh, Use with the LTC4053, LTC1733, or LTC4054 Automatic Switching Between DC Sources, Load Sharing, Replaces ORing Diodes www.linear.com ● www.DataSheet4U.com 6 500mA BAT LTC4068-4.2 1 1µF ITERM + 1-CELL 8 5 Li-Ion EN PROG BATTERY GND ...