LTC4001-1 Linear Technology, LTC4001-1 Datasheet
LTC4001-1
Related parts for LTC4001-1
LTC4001-1 Summary of contents
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... Battery charge current, charge timeout and end-of-charge indication parameters are set with external components. Additional features include shorted cell detection, tempera- ture qualifi ed charging and overvoltage protection. The LTC4001-1 is available in a low profi le (0.75mm) 16-lead (4mm × 4mm) QFN package. SENSE BATSENS ...
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... LTC4001-1 ABSOLUTE MAXIMUM RATINGS (Note INSENSE t < 1ms, DC < 1% .................................... –0. Steady State ............................................. –0. SW, SENSE, BAT, BATSENS, SS, FAULT, CHRG, EN, NTC, PROG, IDET, TIMER Voltage ........................ – 0. Operating Temperature Range (Note 3) .. –40°C to 85°C Operating Junction Temperature (Note 5) ................................................ –40°C to 125°C Storage Temperature Range .................. – ...
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... Note 5: This IC includes overtemperature protection that is intended to protect the device during momentary overload. Junction temperature will exceed 125°C when overtemperature protection is active. Continuous operation above the specifi ed maximum operating junction temperature my impair device reliability. LTC4001-1 = 549Ω 549Ω, unless otherwise PROG IDET ...
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... LTC4001-1 TYPICAL PERFORMANCE CHARACTERISTICS Oscillator Frequency 1. 3.2V BAT 0.75 0.50 0.25 0 –0.25 –0.50 www.DataSheet4U.com –0.75 –1.00 3 3.5 4 4.5 5 5.5 V (V) IN Dissipation of Figure 8 Circuit 1 BAT BAT 1.2 1 1.5A 0.8 BAT 0 BAT 0 500mA BAT 0.2 0 4.25 4.5 4.75 5 5.25 V (V) IN Trickle Charge Current 4.5V ...
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... MOSFET switches. Connect to external inductor. EN (Pin 6): Enable Input Pin. Pulling the EN pin high places the LTC4001-1 into a low power state where the BAT drain current drops to less than 3μA and the supply current is reduced to less than 50μA. For normal opera- tion, pull the pin low ...
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... LTC4001-1 PIN FUNCTIONS NTC (Pin 11): Input to the NTC (Negative Temperature Coeffi cient) Thermistor Temperature Monitoring Circuit. Under normal operation, tie a thermistor from the NTC pin to the GNDSENS pin and a resistor of equal value from NTC When the voltage on this pin is above 0.74V IN (Cold, 0° ...
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... BLOCK DIAGRAM www.DataSheet4U.com BATTERY LOW SHUTDOWN OVERCURRENT ON TRICKLE ON PWM LTC4001-1 40011fa 7 ...
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... LTC4001-1 OPERATION The LTC4001 constant current, constant voltage Li-Ion battery charger based on a synchronous buck architecture. Low power dissipation makes continuous high rate (2A) battery charging practical. The battery DC charge current is programmed by a resistor R DAC output current) at the PROG pin. The fi nal battery fl ...
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... OPERATION Overvoltage, Chip Overtemperature and Short-Circuit Current Protection The LTC4001-1 includes overvoltage, chip overtemperature and several varieties of short-circuit protection. A comparator turns off both chargers (high rate and trickle) if battery voltage exceeds the fl oat voltage by ap- proximately 5%. This may occur in situations where the battery is accidentally disconnected while battery charging is underway ...
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... LTC4001-1 APPLICATIONS INFORMATION Soft-Start and Compensation Capacitor Selection The LTC4001-1 has a low current trickle charger and a PWM-based high current charger. Soft-start is used when- ever the high rate charger is initially turned on, preventing high start-up current. Soft-start ramp rate is set by the internal 12.8μA pull-up current and an external capacitor. ...
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... CHRG pin to an interrupt line. Serrations within this pulse are typically 500ns wide μPROCESSOR 2k OUT IN 40011 F02 LTC4001-1 = Time(Hrs) 0.0733μF). TIMER 20μs 667ms Figure 3. CHRG Temperature Fault Waveform 40011 F03 40011fa 11 ...
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... Grounding the NTC pin disables the NTC function. Thermistors The LTC4001-1 NTC trip points were designed to work with thermistors whose resistance temperature characteristics follow Vishay Dale’s “R-T Curve 2.” However, any thermis- tor whose ratio of R ...
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... The fi nal solution is as shown if Figure 4 where R 121k 13.3k and R = 100k at 25°C. NTC Input and Output Capacitors The LTC4001-1 uses a synchronous buck regulator to provide high battery charging current. A 10μF chip ceramic V INSENSE 9 0.74 • V INSENSE R – ...
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... When the wall adapter reaches current limit, the wall adapter output voltage collapses and the LTC4001-1 PWM charger duty cycle ramps up to 100% (the topside PMOS switch in the LTC4001-1 buck P-P regulator stays on continuously). As the battery voltage ...
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... ADAPTER as the V rises, dropping to zero at V BAT voltage drop in the LTC4001-1 is very low when charge current is highest, power dissipation is also very low. Thermal Calculations (PWM and Trickle Charging) The LTC4001-1 operates as a linear charger when condition- ing (trickle) charging a battery and operates as a high rate buck battery charger at all other times ...
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... Using the LTC4001-1 in Applications Without a Battery www.DataSheet4U.com The LTC4001-1 is normally used in end products that only operate with the battery attached (Figure 6). Under these conditions the battery is available to supply load transient currents. For indefi nite operation with a powered wall adapter there are only two requirements— ...
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... APPLICATIONS INFORMATION www.DataSheet4U.com 500 250 0 0 PWM CHARGE TRICKLE CHARGE TIME (ms TIME (ms TIME (ms) Figure 7. Battery-Less Start-Up LTC4001 40011 F07 40011fa 17 ...
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... For a list of recommend component manufacturers, contact the Linear Technology application department. L1 1.5μH SW SENSE V INSENSE 10μ PGND 10k 1k D1 LED LTC4001-1 CHRG NTC TO μP FAULT EN FROM μP R3 PROG IDET TIMER 10k C2 AT 25°C 0.22μ 549Ω 549Ω ...
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... Plastic QFN (4mm × 4mm) (Reference LTC DWG # 05-08-1692) 0.72 ±0.05 PACKAGE OUTLINE 0.30 ±0.05 0.65 BSC 0.75 ± 0.05 4.00 ± 0.10 (4 SIDES) 2.15 ± 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LTC4001-1 BOTTOM VIEW—EXPOSED PAD PIN 1 NOTCH R = 0.20 TYP OR 0.35 × 45° CHAMFER R = 0.115 TYP 15 16 0.55 ± 0. (UF16) QFN 10-04 0.30 ± 0.05 ...
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... LTC4001-1 RELATED PARTS PART NUMBER DESCRIPTION ® LT 1511 3A Constant-Current/Constant-Voltage Battery Charger LT1513 SEPIC Constant or Programmable Current/Constant- Voltage Battery Charger LT1571 1.5A Switching Charger LTC1729 Li-Ion Battery Charger Termination Controller LT1769 2A Switching Charger www.DataSheet4U.com LTC4001 Monolithic 2A Switchmode Synchronous Li-Ion Battery Charger LTC4002 Standalone Li-Ion Switch Mode Battery Charger LTC4006 Small, High Effi ...