A8439EEJTR-T Allegro Microsystems Inc, A8439EEJTR-T Datasheet
A8439EEJTR-T
Specifications of A8439EEJTR-T
A8439EEJTR-T
Related parts for A8439EEJTR-T
A8439EEJTR-T Summary of contents
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Features and Benefits ▪ Power with 1 Li Alkaline/NiMH/NiCAD batteries ▪ Adjustable output voltage ▪ Auto-refresh ▪ >75% efficiency ▪ Eight-level, digitally-programmable current limit ▪ Charge complete indication ▪ Integrated IGBT driver with trigger ▪ No primary-side Schottky ...
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... A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh Selection Guide Part Number A8439EEJTR-T *Contact Allegro for additional packing options Absolute Maximum Ratings Characteristic SW pin IGBTDRV pin FB pin All other pins Operating Ambient Temperature Maximum Junction Temperature Storage Temperature Package Thermal Characteristics ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh VIN CHARGE I Decoder LIM DONE V IN TRIGGER IGBTDRV Device Pin-out Diagram IGBTDRV VIN 3 8 DONE GND 4 7 TRIGGER CHARGE 5 ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh ELECTRICAL CHARACTERISTICS Characteristics Supply Voltage* Supply Current Primary Side Current Limit (ILIM clock input at CHARGE pin Resistance SW Leakage Current* SW Maximum Off-Time SW Maximum On-Time CHARGE Input ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh V CHARGE SW V OUT DONE TRIGGER IGBTDRV Explanation of Events: A. Start charging by pulling CHARGE to high, provided that V B. Charging stops when V completion of the charging ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh with I set to 1.4A (Single rising edge on CHARGE pin), unless otherwise noted SWLIM Charging Waveforms Symbol Parameter Units/Division C1 V OUT C4 I BATT(Avg) t time Conditions Parameter V ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh Performance Characteristics, continued Tests performed using application circuit shown in figure 8 with I set to 1.4A (Single rising edge on CHARGE pin), unless otherwise noted SWLIM Charge Time V = ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh Performance Characteristics, continued IGBT Drive waveforms are measured with R-C load (12 Ω, 6800 pF) Rising Signal Symbol Parameter Units/Division C2 V IGBTDRV C3 V TRIGGER t time 50 ns Conditions ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh Overview The A8439 is a photoflash capacitor charger control IC with adjustable input current limiting and automatic refresh. It also integrates an IGBT driver for strobe operation of the flash tube, ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh decoder circuit to receive ILIM inputs and set I minimum duration of 54 μs. Figure 5 shows the timing definition of the primary current limiting circuit. At the end of the ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh Figure 7 shows the last charging cycle, when the CHARGE pin is forced low before charging has been completed. The A8439 implements an adaptive off-time, t After the switch is turned ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh Transformer Design The minimum transformer turns ratio, N, Turns Ratio. (Secondary:Primary) should be chosen based on the following formula Drop OUT BATT where: (V) ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh Adjusting Output Voltage The A8439 senses output voltage continuously in order to provide auto-refresh function. The output voltage can be adjusted by selecting proper values of the voltage divider resistors. Use ...
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A8439 Photoflash Capacitor Charger with IGBT Driver and Refresh 3.00 ±0. 11X 0.08 C +0.05 0.25 –0. 0.40 ±0.10 10 Copyright ©2005-2009, Allegro MicroSystems, Inc. The products described here are manufactured under one ...