ltc4002-4.2 Linear Technology Corporation, ltc4002-4.2 Datasheet
ltc4002-4.2
Related parts for ltc4002-4.2
ltc4002-4.2 Summary of contents
Page 1
... After the charge cycle ends, if the battery voltage drops below 4.05V per cell, a new charge cycle will automatically begin. The LTC4002 is available in the 8-lead SO and 10-lead DFN packages. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
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... LTC4002EDD-8.4 GATE 3 GND 4 DD PART MARKING LAGG 8-LEAD PLASTIC 125°C, θ JMAX LBGY (LTC4002-4.2) The ● denotes the specifications which apply over the full = 25° 10V unless otherwise noted CONDITIONS Current Mode Shutdown Mode Sleep Mode 5V ≤ V ≤ 22V (Note ≤ ...
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... CHRG V CHRG Pin Output Low Voltage CHRG R End-of-Charge Ratio EOC t Charge Time Accuracy TIMER I NTC Pin Output Current NTC (LTC4002-4.2) The ● denotes the specifications which apply over the full = 25° 10V unless otherwise noted CONDITIONS V = 0.85V NTC V Falling ...
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... GATE = V – V ∆V GATELO CC GATE Note 4: The LTC4002 is guaranteed to meet performance specifications from 0°C to 70°C. Specifications over the – 40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls 25° Supply Current vs V ...
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... CHRG 25 21 – 50 – 100 125 TEMPERATURE (°C) 4002 G08 Recharge Voltage Offset from Full Charged Voltage 160 LTC4002-4.2 150 140 (V) CC 4002 G11 LTC4002 = 10V unless otherwise noted. CC CHRG Pin Output Low Voltage ...
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... CC COMP Pin Output Current vs Temperature 104 COMP 100 96 25 – 50 – TEMPERATURE (°C) Trickle Charge Voltage 3.0 LTC4002-4.2 2 25° 10V unless otherwise noted Current Mode Sense Voltage 102 BAT LTC4002-8.4 ...
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... 2.5V BAT LTC4002-4 125 (V) CC 4002 G23 NTC Pin Output Current vs Temperature NTC – 50 – TEMPERATURE (°C) 4002 G26 CC LTC4002-4 (V) CC 4002 G29 20 25 4002 G24 75 100 125 4002 G27 4002f 7 ...
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... When the voltage at this pin drops below 355mV 25° 10V unless otherwise noted LTC4002-8 (V) CC 4002 G31 is within 250mV the LTC4002 is forced CC to 10µ must be connected between the SENSE . 4002f ...
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... SLOP L – PWM SLOP R IL UVLO 4. EOC – LOGIC C/10 Q4 STOP TEMP Q5 NTC_DISABLE 25µA GND LTC4002 DRIVER GATE 25mV or 10mV + – EOC – 100mV SENSE + + – CA – BAT + VA – 4.2V/CELL + C LB – 2. – 4.62V/CELL + C RQ – ...
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... VA + LTC4002 U OPERATIO The LTC4002 is a constant current, constant voltage Li-Ion battery charger controller that uses a current mode PWM step-down (buck) switching architecture. The charge current is set by an external sense resistor (R across the SENSE and BAT pins. The final battery float voltage is internally set to 4.2V per cell. For batteries like lithium-ion that require accurate final float voltage, the internal 2 ...
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... CHRG pin is forced high impedance. Shutdown The LTC4002 can be shut down by pulling the COMP pin to ground which pulls the GATE pin high turning off the external P-channel MOSFET. When the COMP pin is re- leased, the internal timer is reset and a new charge cycle starts ...
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... Gate Drive The LTC4002 gate driver can provide high transient cur- rents to drive the external pass transistor. The rise and fall times are typically 20ns and 50ns respectively when ...
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... Choose the inductor for about 65% ripple current at the is approxi- OUT maximum ⎞ ( 500 ⎟ ⎠ Selecting a standard value of 6.8µH results in a maximum ripple current ∆ LTC4002 = 5V to 22V nominal BAT = 500kHz, see Figure 2. = 100mV/1.5A = 68mΩ ⎛ ⎞ 1 – ...
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... W U Board Layout Suggestions When laying out the printed circuit board, the following considerations should be taken to ensure proper opera- tion of the LTC4002. GATE pin rise and fall times are 20ns and 50ns respectively (with C GATE W diode, pass transistor and the input bypass capacitor traces should be kept as short as possible ...
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... TYP .016 – .050 .014 – .019 (0.406 – 1.270) (0.355 – 0.483) TYP INCHES (MILLIMETERS) LTC4002 R = 0.115 0.38 ± 0.10 TYP 6 10 3.00 ±0.10 1.65 ± 0.10 (2 SIDES) (4 SIDES 0.25 ± 0.05 0.75 ± ...
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... Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 2-Cell 8.4V, 2A Li-Ion Battery Charger R1 100k M2 1/2 Si9933ADY 0.1µ CER GATE 1/2 Si9933ADY LTC4002ES8-8.4 L1 6.8µ CHRG SENSE R SENSE 50mΩ COMP BAT C2 NTC GND C C 22µF 0.47µF ...