LTC4012-2 Linear Technology Corporation, LTC4012-2 Datasheet
LTC4012-2
Related parts for LTC4012-2
LTC4012-2 Summary of contents
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... With no built-in termination, the LTC4012 family charges a wide range of batteries under external control. The LTC4012 features fully adjustable output voltage, while the LTC4012-1 and LTC4012-2 can be pin-programmed for Lithium-Ion/Polymer battery packs of 1-, 2 4-series cells. The LTC4012-1 provides output voltage of 4.1V/cell and the LTC4012 ...
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... BOOST to SW............................................... –0. SHDN, FVS0, FVS1 or V ACP, CHRG or ICL to GND ......................... –0.3V to 30V Operating Temperature Range (Note 2) ........................................................ 0°C to 85°C Junction Temperature (Note 3) ............................. 125°C Storage Temperature Range ...................–65°C to 150°C LTC4012-1 LTC4012-2 CSP 15 CSN 14 13 PROG ITH ...
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... Overvoltage Threshold BOV FB BAT Overvoltage Threshold Charge Current Regulation I Charge Current Accuracy with R TOL 6V < BAT < 18V (LTC4012) 6V < BAT < 15V (LTC4012-1, LTC4012-2) A Current Sense Amplifi er Gain (PROG ΔI) with 3.01k, 6V < BAT < 18V (LTC4012 < BAT < 15V (LTC4012-1, LTC4012-2) V ...
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... V INFET Output Low Voltage, Relative to CLP OL(INFET) V INFET Output High Voltage, Relative to CLP OH(INFET) t INFET Turn-On Time IF(ON) t INFET Turn-Off Time IF(OFF) Float Voltage Select Inputs (LTC4012-1/LTC4012-2 Only) V Input Voltage Low IL V Input Voltage High IH I Input Current IN Indicator Outputs V Output Voltage Low ...
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... CLN) – – EA – + 1.2085V PROG 1.2085V TARGET LTC1055 – LTC4012-1 FROM ICL LTC4012-2 (CLP = CLN) – – EA – + 1.2085V PROG BAT TARGET VARIES WITH FVSO,1 LTC1055 – LTC4012/ LTC4012-1/LTC4012-2 ITH 12 0.6V 40012 TC01 ITH 12 0.6V 40012 TC02 4012f 5 ...
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... LTC4012/ LTC4012-1/LTC4012-2 www.DataSheet4U.com TYPICAL PERFORMANCE CHARACTERISTICS (T = 25°C unless otherwise noted IHLP-2525 6.8μH) A Effi ciency at DCIN = 20V, BAT = 8V 100 R = 33mΩ SENSE R = 3.01k IN 95 EFFICIENCY 0.5 1 1.5 CHARGE CURRENT (A) Effi ciency at DCIN = 20V, BAT = 16V 100 EFFICIENCY 95 90 ...
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... Battery Shutdown Current 25 DC1256-CLASS APPLICATION DCIN = LTC4012, ALL PINS DCIN = 0V 10 LTC4012, BAT PINS DCIN = 20V BATTERY VOLTAGE (V) 4012 G14 LTC4012/ LTC4012-1/LTC4012-2 Input Current Limit 3.0 2 2.0 I CHG 1.5 1.0 0.5 2.5A BULK CHARGE 2.1A INPUT CURRENT LIMIT 0 ICL STATE –0.5 –1.0 0.5 1.0 12.6 13.0 0 SYSTEM LOAD (A) ...
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... PFET output to BAT with an operating voltage range of GND to BAT. FVS1 (Pin 10, LTC4012-1/LTC4012-2): Battery Voltage Select Input (MSB). This pin is one of two pins used on the LTC4012-1 or LTC4012-2 to select one of four preset battery voltages. Selection is done by connecting to either GND or INTV DD to INTV ...
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... LTC4012 circuits. It must be soldered to a suitable PCB copper ground pad for proper electrical operation and to obtain the specifi ed package thermal resistance. . BGATE should be DD LTC4012/ LTC4012-1/LTC4012-2 . Refer to the Applications DD – 1V) to (CLN + 5V). 4012f 9 ...
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... LTC4012/ LTC4012-1/LTC4012-2 www.DataSheet4U.com BLOCK DIAGRAM DCIN 4 – INFET CLP 2 CLN 1 ICL 8 CHRG SHUTDOWN SHUTDOWN SHDN 6 CONTROL TO INTERNAL CIRCUITS ACP 5 BAT 11 OSCILLATOR FBDIV 10 10 (LTC4012) INPUT CURRENT LIMIT C/10 DETECTION + CC – TO INTERNAL CIRCUITS CHARGE FAULT DETECTION – R1 – EA – ...
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... CIRCUITS FVS1 10 Output FVS0 Voltage 9 Select BAT 11 ACP 5 OSCILLATOR (LTC4012-1/LTC4012-2) INPUT CURRENT LIMIT C/10 DETECTION – TO INTERNAL CIRCUITS CHARGE LTC4012/ LTC4012-1/LTC4012-2 FAULT DETECTION R1 – – EA – + 1.2085V REFERENCE PWM LOGIC TO INTERNAL CIRCIUTS 5V REGULATOR CSP + 15 CA CSN – 14 PROG 13 ITH ...
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... Due to the popularity of rechargeable Lithium-Ion chemistries, the LTC4012-1 and LTC4012-2 also offer internal precision resistors that can be digitally selected to produce one of four preset output voltages for simplifi ed design of those charger types ...
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... Figure 1, the nominal PROG voltage is given PROG Voltage tolerance on PROG is limited by the charge current accuracy specifi the Electrical Characteristics table. Refer to the Applications Information section on programming charge current for additional details. LTC4012/ LTC4012-1/LTC4012-2 SYSTEM POWER TGATE 19 L1 BGATE 16 R ...
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... LTC4012/ LTC4012-1/LTC4012-2 www.DataSheet4U.com OPERATION Adapter Input Current Limit The LTC4012 can monitor and limit current from the input DC supply, which is normally an AC adapter. When the programmed adapter input current is reached, charge current is reduced to maintain the desired maximum input current. The ITH and PROG pins will refl ect the reduced charge current ...
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... An internal watchdog timer observes the activity on the TGATE pin. If TGATE is on for more than 40μs, the watchdog activates and forces the bottom NFET on (top NFET off) LTC4012-1/LTC4012-2 for about 100ns. This avoids a potential source of audible noise when using ceramic input or output capacitors and prevents the boost supply capacitor for the top gate driver ...
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... LTC4012/ LTC4012-1/LTC4012-2 www.DataSheet4U.com APPLICATIONS INFORMATION Programming Charge Current The formula for charge current is: ⎛ 2085 . • ⎝ ⎜ CHRG R R SENSE PROG The LTC4012 operates best with 3.01k input resistors, although other resistors near this value can be used to accommodate standard sense resistor values ...
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... A value of 10pF is normally adequate. Table 2. Programming Output Voltage R2A R2B* 4012 F05 = + , *To Obtain Desired Accuracy Requires Series Resistors For R2. LTC4012/ LTC4012-1/LTC4012-2 ⎛ ⎞ BAT = + R 2 ⎜ – ⎟ ⎝ ⎠ ...
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... The LTC4012-1/LTC4012-2 feature precision internal bat- tery voltage feedback resistor taps confi gured for common lithium-ion voltages. All that is required to program the desired voltage is proper pin programming of FVS0 and FVS1 as shown in Table 3. Table 3. LTC4012-1/LTC4012-2 Output Voltage Programming V VOLTAGE BAT LTC4012-1 LTC4012-2 4 ...
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... When monitoring the PROG pin voltage, using a buffer amplifi shown in Figure 8 will minimize charge current errors. The buffer amplifi er may be powered from the INTV charger is on. LTC4012/ LTC4012-1/LTC4012-2 values are needed to allow two LIM for the high power LIM LIM ...
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... LTC4012/ LTC4012-1/LTC4012-2 www.DataSheet4U.com APPLICATIONS INFORMATION C/10 CHRG Indicator The value chosen for R PROG on charge current monitoring and the accuracy of the C/10 charge indicator output (CHRG). The LTC4012 uses the voltage on the PROG pin to determine when charge current has dropped to the C/10 threshold. The nominal threshold of 400mV produces an accu- ...
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... A reasonable starting point for setting ripple current is ΔI = 0.4 • LTC4012 circuits also imposes limits on ripple current. Select R high ripple designs. The following equation can be used for guidance: R SENSE 50 LTC4012/ LTC4012-1/LTC4012-2 decreases with L ⎛ ⎞ V ⎜ BAT ⎟ V • – 1 BAT ⎝ ...
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... LTC4012/ LTC4012-1/LTC4012-2 www.DataSheet4U.com APPLICATIONS INFORMATION R should not be less than 2.37k or more than 6.04k. Val- IN ues of R greater than 3.01k may cause some reduction in IN programmed current accuracy. Use these equations and guidelines, as represented in Table 6, to help select the cor- rect inductor value. This table was developed to maintain maximum Δ ...
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... ITH pin and GND. As shown in the typical LTC4012 application, a 6.04k resistor in series but lower C can RSS with a capacitor of at least 0.1μF provides adequate loop compensation for the majority of applications. LTC4012/ LTC4012-1/LTC4012-2 that exceeds the maximum V DSS , to avoid overlap conduction losses. Switching CLP 4012f 23 ...
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... LTC4012/ LTC4012-1/LTC4012-2 www.DataSheet4U.com APPLICATIONS INFORMATION The LTC4012 can be soft-started with the compensation capacitor on the ITH pin. At start-up, ITH will quickly rise to about 0.25V, then ramp rate set by the com- pensation capacitor and the 40μA ITH bias current. The full programmed charge current will be reached when ITH reaches approximately 2V. With a 0.1μ ...
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... LTC4012-1/LTC4012 good rule of thumb for via count in a given high current path is to use 0.5A per via. Be consistent when applying this rule. ...
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... LTC4012/ LTC4012-1/LTC4012-2 www.DataSheet4U.com TYPICAL APPLICATION FROM ADAPTER 15V 0.1μ TO/FROM MCU C2 0.1μF R4 6.04k C3 R5 4.7nF 26.7k BULK R6 Q1 CHARGE 53.6k 26 12.6V 4 Amp Charger R7 25mΩ 0.1μF CHRG INFET 5. DCIN CLP 1 CLN R15 20 0Ω* BOOST C5 0.1μF ...
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... Plastic QFN (4mm × 4mm) (Reference LTC DWG # 05-08-1710 Rev A) 0.70 ±0.05 2.45 ± 0.05 PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC 0.75 ± 0.05 4.00 ± 0.10 2.00 REF 0.200 REF 0.00 – 0.05 LTC4012/ LTC4012-1/LTC4012-2 BOTTOM VIEW—EXPOSED PAD 0.115 TYP TYP 19 20 0.40 ± 0. 2.45 ± 0.10 2.45 ± 0.10 (UF20) QFN 01-07 REV A 0.25 ± ...
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... LTC4012/ LTC4012-1/LTC4012-2 www.DataSheet4U.com RELATED PARTS PART NUMBER DESCRIPTION LTC1760 Smart Battery System Manager LTC1769 2A Switching Battery Charger LTC1960 Dual Battery Charger/Selector with SPI LTC4006 Small, High Effi ciency, Fixed Voltage, Lithium-Ion Battery Chargers with Termination LTC4007 High Effi ciency, Programmable Voltage, Lithium-Ion ...