LTC4007-1 Linear Technology, LTC4007-1 Datasheet
LTC4007-1
Related parts for LTC4007-1
LTC4007-1 Summary of contents
Page 1
... A timer, programmed by an external resistor, sets the total charge time. The LTC4007-1 includes a thermistor input, which sus- pends charging if an unsafe temperature condition is de- tected. If the cell voltage is less than 3.25V, a low-battery indicator asserts and can be used to program a trickle charge current to safely charge depleted batteries ...
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... LTC4007 ABSOLUTE MAXIMUM (Note 1) Voltage from DCIN, CLP, CLN to GND ....... + 32V/– 0.3V PGND with Respect to GND ................................. ±0.3V CSP, BAT to GND ....................................... +28V/– 0.3V CHEM, 3C4C GND .............................. +7V/– 0.3V T NTC ............................................................ +10V/– 0.3V ACP, SHDN, CHG, FLAG, FAULT, LOBAT .............................................. CLP to CLN ........................................................... ±0.5V Operating Ambient Temperature Range (Note 4) ............................................. – ...
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... INFET V Rising NTC V Falling NTC ≤ 10V V NTC , FAULT CL Voltage Falling at PROG 3C4C = 0V, CHEM = 0V 3C4C = 0V, CHEM = Open 3C4C = Open, CHEM = 0V 3C4C = Open, CHEM = Open LTC4007-1 www.DataSheet4U.com = 12V unless otherwise noted. BAT MIN TYP MAX 11.67 ● 0 ● V – 0.2 CLN ● 140 165 200 – ...
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... LTC4007-1 ELECTRICAL CHARACTERISTICS temperature range (Note 4), otherwise specifications are at T SYMBOL PARAMETER V Low Logic Level of ACP, CHG, FLAG, LOBAT FAULT CL V High Logic Level of CHG, LOBAT Off State Leakage Current of ACP, FLAG, FAULT OFF I Pull-Up Current on CHG, LOBAT ...
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... LOAD CURRENT = 1A, 2A, 3A DCIN = 20V V = 12.6V (3C4C = GND, CHEM = OPEN) FLOAT Battery Leakage Current vs Battery Voltage 40 VDCIN = 40071 G07 LTC4007-1 www.DataSheet4U.com OUT OUT 0 –0.5 –1.0 –1.5 –2.0 –2.5 –3.0 –3.5 –4.0 3C4C = GND –4.5 3C4C = OPEN –5.0 ...
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... LTC4007 TYPICAL PERFOR A CE CHARACTERISTICS Efficiency at 19VDC V 100 16.8V 95 12. 0.50 1.00 1.50 CHARGE CURRENT ( CTIO S ACP(Pin 1): Open-Drain output to indicate if the AC adapter voltage is adequate for charging. This pin is pulled low by an internal N-channel MOSFET if DCIN is below BAT. A pull-up resistor is required. The pin is capable of sinking at least 100µ ...
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... N-channel MOSFET. Internal 10µA pull-up to 3.5V greater than 3.3V, add an external pull-up. The LOGIC timer function can be defeated by forcing this pin below 1V (or connecting it to GND). Exposed Pad (Pin 25): The exposed pad, GND and PGND should be connected together with a low ohmic connec- tion. LTC4007-1 40071f 7 ...
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... LTC4007-1 W BLOCK DIAGRA 0.1µ DCIN 23 5.8V INFET Q3 21 ACP 1 SHDN 22 FAULT 3 FLAG 14 GND 4 3C4C 5 CHEM 13 + LOBAT 6 – 921mV 1.19V 5k CLP Ω – 1. 15nF CL1 CL 100mV CLN + DCIN OSCILLATOR WATCHDOG 20µF DETECT t OFF 1.28V CLN TGATE BGATE ...
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... TEST CIRCUIT U OPERATIO Overview The LTC4007 synchronous current mode PWM step-down (buck) switcher battery charger controller. The charge current is programmed by the combination of a program resistor (R ) from the PROG pin to ground PROG and a sense resistor (R ) between the CSP and BAT SENSE pins. The final float voltage is programmed to one of four values (12.3V, 12.6V, 16.4V, 16.8V) with ± ...
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... LTC4007-1 U OPERATIO Table 1. Truth Table for LTC4007-1 Operation (Supplemental) FROM TO NUMBER STATE STATE MODE 1 Any MSD Shut Down by Low Adapter Voltage 2 MSD SD Charger Shutdown 3 SD, SD Shut Down by CONDITION, Undervoltage Lockout CHARGE 4 SD CONDITION Start Conditioning a Depleted Battery 5 CONDITION CONDITION Input Current Limited ...
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... ACP pin is driven low and the charger is disabled. Battery Charger Controller The LTC4007-1 charger controller uses a constant off- time, current mode step-down architecture. During nor- mal operation, the top MOSFET is turned on each cycle when the oscillator sets the SR latch and turned off when ...
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... LTC4007-1 U OPERATIO adjusts ITH until: + µ – REF = CSP BAT Ω PROG therefore, ⎛ V REF = ⎜ I – CHARGE MAX ( ) ⎝ R PROG The voltage at BAT is divided down by an internal resistor divider and is used by error amp EA to decrease ITH if the divider voltage is above the 1 ...
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... Q C Figure 3 t SAMPLE t HOLD VOLTAGE ACROSS THERMISTOR COMPARATOR HIGH LIMIT COMPARATOR LOW LIMIT Figure 4 LTC4007-1 www.DataSheet4U.com • 17.5pF = 54µ 309k interval ends the result of the thermistor HOLD to zero and charging will BAD to one, the charger BAD returns to zero (see Figure 4). ...
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... For example, the desired max charging current is 2.5A but R (kΩ) 1% the best R PROG 26.7 across R 26.7 82.5mV, normally R 26.7 FLAG trip point is only 5% of maximum charging current. 26.7 If the input resistors are reduced by the same amount as www.DataSheet4U.com LTC4007-1 PROG PROG 102k PROG 5V Q1 2N7002 0V ...
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... It is important to keep the parasitic capacitance on the R pin to a minimum. The trace connecting short as possible. Soft-Start The LTC4007-1 is soft started by the 0.12µF capacitor on the I pin. On start-up, ITH pin voltage will rise quickly to TH 0.5V, then ramp rate set by the internal 40µA pull- up current and the external capacitor ...
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... LTC4007 APPLICATIO S I FOR ATIO used when tantalum capacitors are used for input or output bypass . High input surge currents can be created when the adapter is hot-plugged to the charger or when a battery is connected to the charger. Solid tantalum capaci- tors have a known failure mechanism when subjected to very high turn-on surge currents. Only Kemet T495 series of “ ...
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... The diode may be omitted if the efficiency loss can be tolerated. DS(ON) Calculating IC Power Dissipation ) OSC (1 + δ∆T)R 2 The power dissipation of the LTC4007-1 is dependent ) DS(ON) upon the gate charge of the top and bottom MOSFETs and DS(ON) (QG1 & QG2 respectively) The gate charge is determined from the manufacturer’s data sheet and is dependent upon both the gate voltage swing and the drain voltage swing of the MOSFET ...
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... U U APPLICATIO S I FOR ATIO Adapter Limiting An important feature of the LTC4007-1 is the ability to automatically adjust charging current to a level which avoids overloading the wall adapter. This allows the prod- uct to operate at the same time that batteries are being charged without complex load management algorithms. ...
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... R ) TH(LOW • R Example 24. 309k (~2 hour timer 0.57µF → 0.56µF (nearest value) LTC4007-1 www.DataSheet4U.com = 272.05k at 5°C = 33.195k at 50°C = 6.53k at 0°C = 61.4k at 50°C /(R9/7 • –ln(1 – 8 • 15mV/4.5V)) • 17.5pF/(R9/7 • – ln(1 – 8 • 15mV/4.5V) RT 40071f ...
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... Severely depleted batteries, with less than 3.25V/cell, should be conditioned with a trickle charge to prevent possible damage. This trickle charge is typically 10% of the 1C rate of the battery. The LTC4007-1 can automati- cally trickle charge depleted batteries using the circuit in Figure 11. If the battery voltage is less than 3.25V/cell (3 ...
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... For best current programming accuracy provide a Kelvin connection from R Figure example important to keep the parasitic capacitance on the R CSP and BAT pins to a minimum. The traces connecting these pins to their respective resistors should be as short as possible. LTC4007-1 www.DataSheet4U.com to CSP and BAT. See SENSE , T 40071f ...
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... C7 THERMISTOR 0.47µ TIMING RESISTOR 309k (~2 HOURS) 1% Figure 11. Circuit Application (16.8V/3A) to Automatically Trickle Charge Depleted Batteries INPUT SWITCH C1 0.1µF DCIN C4 INFET 15nF CLP LTC4007-1 CLN TGATE BGATE PGND R4 CSP 3.01k 1% BAT R5 3.01k 1% PROG ITH R7 GND C5 6.04k 0.0047µF 1% R14 C6 52.3k 0.12µF 1% www ...
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... DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LTC4007-1 www.DataSheet4U.com DIRECTION OF CHARGING CURRENT R SENSE ...
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... McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 12.6V, 4A Li-Ion Battery Charger Q3 INPUT SWITCH C1 R1 0.1µF 4.99k 1% 3C4C DCIN C4 CHEM INFET 15nF LOBAT CLP I LTC4007-1 CLN CL ACP TGATE SHDN BGATE FAULT PGND CHG CSP R4 3.01k 1% FLAG BAT R5 3.01k 1% NTC PROG R ITH T ...