LT1571-1 LINER [Linear Technology], LT1571-1 Datasheet
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LT1571-1
Related parts for LT1571-1
LT1571-1 Summary of contents
Page 1
... A logic output (flag) indicates Li-Ion near full charge when the charge current drops to 20% of the programmed value. The LT1571-1 and LT1571-2 are in a 28-pin fused lead narrow SSOP power package. The LT1571 16-pin fused lead narrow SSOP power package ...
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... LT1571 Series ABSOLUTE AXI U RATI GS Supply Voltage (V ) .............................................. 28V CC BOOST Pin Voltage with Respect to V FLAG Pin Voltage ..................................................... V I (Average)........................................................ 1.5A BAT Switch Current (Peak) .............................................. 2A Storage Temperature Range ................. – 150 C U PACKAGE/ORDER I FOR ATIO TOP VIEW **GND 1 16 GND ...
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... ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are 16V (LT1571-1, LT1571-2 10V (LT1571-5 26V, no load on any outputs unless otherwise noted. (Note 6) CC MAX PARAMETER Overall Supply Current DC Battery Charging Current, I ...
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... LT1571 Series ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are 16V (LT1571-1, LT1571-2 10V (LT1571-5 26V, no load on any outputs unless otherwise noted. (Note 6) CC MAX PARAMETER Switch Switch ON Resistance ...
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... For other battery voltages, use the adjustable LT1571-1. BOOST V (LT1571-1): This is the input to the amplifier VA (see FB Block Diagram) with a threshold of 2.465V. Typical input current is about 3nA. When charging batteries, VA moni- tors the battery voltage and reduces charging current when battery voltage reaches the preset value ...
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... CAP + FLAG E6 – NOTES: LT1571- 7.1k 30.24k LT1571- 3.33k 8.62k LT1571-1: 200kHz, V PIN FOR ADJUSTABLE FB BATTERY VOLTAGE (V PIN IS NOT INTERNALLY FB CONNECTED TO THE RESISTORS) LT1571-2: 200kHz, PRESET 8.2V CELL (SELECT PIN OPEN) OR 8.4V (SELECT PIN GROUNDED) LT1571-5: 500KHz, PRESET 4.1V CELL (SEECT PIN OPEN) OR 4.2V (SELECT PIN GROUNDED) ...
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... Soft-Start The LT1571 is soft-started by the 0.3 F capacitor on V pin. On start-up, the V then ramp at a rate set by the internal 45 A pull-up current and the external capacitor. Charge current starts ramping ...
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... This situation can be prevented by utilizing undervoltage lockout , set higher than the minimum adapter voltage where full power can be achieved. A fixed undervoltage lockout built into the LT1571. A higher lockout voltage can be implemented with a Zener diode D2 (see Figure 2). ...
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... U U APPLICATIO S I FOR ATIO Lithium-Ion Charging The circuit in Figure 4 uses the 28-pin LT1571-2 to charge lithium-ion batteries at a constant 1A until the battery voltage reaches 8.4V preset battery voltage. The charger will then automatically go into a constant-voltage mode with current decreasing to near zero over time as the battery reaches full charge ...
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... Removing input power to the charger puts the LT1571 into a sleep mode and draws only 5 A from the battery. Nickel-Cadmium and Nickel-Metal-Hydride Charging The circuit in Figure 7 uses the LT1571-1 to charge NiCd or NiMH batteries up to 20V with charge currents of 0.5A when and 50mA when Q1 is off. ...
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... U U APPLICATIO S I FOR ATIO C1 D1 0.22 F 1N5819 BOOST PROG 1 F L1** 300 33 H LT1571-1 D2 1N914 GND V 0 BAT SENSE BAT + C OUT * TOKIN OR MARCON CERAMIC 22 F SURFACE MOUNT TANT ** COILTRONICS CTX33-2 Figure 7. Charging NiMH or NiCd Batteries with Constant Current (Efficiency at 0.5A 90%) lower value and maintained as a constant trickle charge. An intermediate “ ...
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... EMI. Higher Duty Cycle Maximum duty cycle for the LT1571-1/LT1571-2 is typi- cally 90% but this may be too low for some applications. For example 18V 3% adapter is used to charge ten NiMH cells, the charger must put out approximately 15V. ...
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... F Q1: Si4435DY Q2: TP0610L HIGH DUTY CYCLE CONNECTION Figure 11. Replacing the Input Diode Figure 13. Critical Electrical and Thermal Path Layer for LT1571 Layout Considerations Switch rise and fall times are under 10ns for maximum efficiency. To minimize radiation, the catch diode, SW pin and input bypass capacitor leads should be kept as short as possible ...
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... LT1571 Series PACKAGE DESCRIPTIO 0.007 – 0.0098 (0.178 – 0.249) 0.016 – 0.050 (0.406 – 1.270) * DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE ...
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... TYP 0.008 – 0.012 (0.203 – 0.305) LT1571 Series 0.386 – 0.393* 0.033 (9.804 – 9.982) (0.838 1615 REF 0.150 – ...
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... LT1571 Series RELATED PARTS PART NUMBER DESCRIPTION LT1505 High Current Constant-Current/Constant-Voltage Battery Charger Controller with Input Current Limit LT1510 200kHz Constant-Current/Constant-Voltage Battery Charger LT1510-5 500kHz Constant-Current/Constant-Voltage Battery Charger LT1511 200kHz Constant-Current/Constant-Voltage Battery Charger with Input Current Limit LT1512 500kHz SEPIC Constant-Current/Constant-Voltage ...