LTC4071 LINEAR [Linear Integrated Systems], LTC4071 Datasheet
LTC4071
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LTC4071 Summary of contents
Page 1
... The unique architecture of the LTC4071 allows for an extremely simple battery charger solution, requiring just one external resistor. The LTC4071 offers a pin selectable float voltage with ±1% accuracy. The integrated thermal battery qualifier extends battery lifetime and improves reliability by automatically reducing the battery float voltage at NTC thermistor tem- peratures above 40° ...
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... LTC4071EDDB#PBF LTC4071EDDB#TRPBF LTC4071IDDB#PBF LTC4071IDDB#TRPBF LTC4071EMS8E#PBF LTC4071EMS8E#TRPBF LTC4071IMS8E#PBF LTC4071IMS8E#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: ...
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... Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC4071 is tested under pulsed load conditions such that T ≈ The LTC4071E is guaranteed to meet performance specifications ...
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... LTC4071 Typical perForMance characTerisTics LBC vs I BAT 4.3 LBSEL = GND 4.1 3.9 3.7 LBSEL = V CC 3.5 3.3 3.1 2.9 0.01 0 (mA) BAT 4071 G01 R vs Temperature DS(ON) 5.5 5.0 4.5 4.0 3.5 3.0 –50 – 100 TEMPERATURE (°C) 4071 G04 HBO Thresholds vs Temperature 250 ADJ = V CC LBSEL = V CC NTC = NTCBIAS 200 150 HBOHY 100 ...
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... LBSEL = V 3. 100 125 0 4071 G13 NTCBIAS Period vs Temperature 100 125 –50 4071 G15 LTC4071 T = 25°C, unless otherwise noted. A HBO V OL 1200 LBSEL = V CC NTC = NTCBIAS 900 600 V CC 300 2.5 I (mA) ...
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... LTC4071 pin FuncTions NTCBIAS (Pin 1): NTC Bias Pin. Connect a resistor from NTCBIAS to NTC, and a thermistor from NTC to GND. Float NTCBIAS when not in use. Minimize parasitic capacitance on this pin. NTC (Pin 2): Input to the Negative Temperature Coefficient Thermistor Monitoring Circuit. The NTC pin connects to ...
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... CHG As the battery voltage approaches the float voltage, the LTC4071 shunts current away from the battery thereby reducing the charge current. The LTC4071 can shunt up to 50mA. The shunt current limits the maximum charge current. LTC4071 ...
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... HBO pin pulls low to indicate that the battery is HBHY not at full charge. The input supply current to the LTC4071 drops to less than 550nA (typ) as the LTC4071 no longer shunts current to protect the battery. And the NTCBIAS sample clock slows to conserve power. For example, if the NTC thermistor requires the float voltage to be dropped by 100mV (ADJ = V programming ...
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... If the voltage of a Li-Ion cell drops below a certain level, the cell may be permanently damaged. Disconnecting the battery from V prevents the load well as the LTC4071 quiescent CC current from further discharging the battery. Once disconnected the V voltage collapses towards CC ground ...
Page 10
... General Charging Considerations The LTC4071 uses a different charging methodology from previous chargers. Most Li-Ion chargers terminate the charging after a period of time. The LTC4071 does not have a discrete charge termination. Extensive measurements on Li-Ion cells show that the cell charge current drops to very low levels with the shunt charge control circuit effectively terminating the charge ...
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... TH example tor) then the temperature trip points are 41.0°C, 49.8°C, 58.5°C and 67.3°C. When using the NTC features of the LTC4071 it is important to keep in mind that the maximum shunt current increases as the float voltage, V about once every 1.5 Reviewing the single-cell battery charger application with a 12V wall adapter in Figure 2 ...
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... CC C Li-Ion BYPASS 4071 F04 Take care to select a bypass capacitor with low leakage. The LTC4071 can be used to charge a battery to a 4.2V float voltage from an AC line with a bridge rectifier as shown in the simple schematic in Figure 5. In this example, DANGER! HIGH VOLTAGE RESISTANCE V MIN 5k to 10k 3 ...
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... UL leakage in the event that one of the resistors short. Here, the LTC4071 will fully charge the battery from the AC line while meeting the UL specification with 104µA of available charge current. A simple photovoltaic (PV) application for the LTC4071 is illustrated in Figure 6 ...
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... LTC4071 and then the entire device is latched-off, leaving the battery fully charged but with the LTC4071 switched off. The co-packaged battery and LTC4071 can then be stored with a long shelf-life before being activated for normal use. ...
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... DDB Package 8-Lead Plastic DFN (3mm × 2mm) (Reference LTC DWG # 05-08-1702 Rev B) 3.00 ±0.10 (2 SIDES) 2.00 ±0.10 PIN 1 BAR (2 SIDES) TOP MARK (SEE NOTE 6) 0.75 ±0.05 0.200 REF 0 – 0.05 LTC4071 R = 0.115 0.40 ± 0.10 TYP TYP PIN 0.20 OR 0.25 × 45° 0.56 ± 0.05 CHAMFER (2 SIDES) ...
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... LTC4071 package DescripTion Please refer to http://www.linear.com/designtools/packaging/ 1.88 ± 0.102 (.074 ± .004) 5.23 (.206) MIN 0.42 ± 0.038 (.0165 ± .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE DETAIL “A” 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006" ...
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... Updated MFR part number on the Typical Application circuit MEC201-10P . 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC4071 PAGE NUMBER 3 11, 12, 13, ...
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... Li-Ion/Polymer Shunt Battery Charger System 18 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● V BAT CC NTCBIAS 10k LTC4071 NTC GMB031009 LBSEL + GND OR GS NANO T* OR MEC201-10P *NTHS0402N02N1002F COMMENTS A High Efficiency Step-Up DC/DC Converter That Can Operate from Input Voltage As Low As 200mV ...