A8436EEJTR-T Allegro Microsystems Inc, A8436EEJTR-T Datasheet
A8436EEJTR-T
Specifications of A8436EEJTR-T
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A8436EEJTR-T Summary of contents
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Photoflash Capacitor Charger with IGBT Driver Features and Benefits ▪ Power with 1 Li Alkaline/NiMH/NiCAD batteries ▪ Adjustable output voltage ▪ >75% efficiency ▪ Three levels of switch current limit: 1.0, 1.2, 1.4 A ▪ Fast charge time ...
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... Description (continued) Applications include: ▪ Digital camera flash ▪ Film camera flash ▪ Cell phone flash ▪ Emergency strobe light Selection Guide Part Number A8436EEJTR-T A8436ELZTR-T *Contact Allegro for additional packing options Absolute Maximum Ratings Characteristic SW pin IGBTDRV pin FB pin All other pins ...
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A8436 VIN ILIM I Decoder LIM CHARGE DONE V IN TRIGGER IGBTDRV Device Pin-out Diagrams ILIM 2 9 IGBTDRV VIN DONE 4 7 GND TRIGGER 5 6 CHARGE SW Package EJ ILIM NC 10 ...
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A8436 ELECTRICAL CHARACTERISTICS Characteristics Supply Voltage* Supply Current Primary Side Current Limit SW On Resistance SW Leakage Current* SW Maximum Off-Time SW Maximum On-Time CHARGE Input Current CHARGE Input Voltage* ¯ D ¯ ¯ O ¯ ¯ N ¯ ¯ ...
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A8436 V UVLO VIN CHARGE SW Target V OUT 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 process. C. Start ...
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A8436 Tests performed using application circuit shown in figure 6 (unless otherwise noted) Charging Waveforms Symbol Parameter Units/Division C1 V OUT C4 I BATT(Avg) t time Conditions Parameter V BATT V BIAS C OUT Symbol Parameter Units/Division C1 V OUT ...
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A8436 Performance Characteristics, continued Tests performed using application circuit shown in figure 6 (unless otherwise noted) Charge Time BIAS Connect VBATT to a separate power supply ...
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A8436 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 Parameter Value t 22.881 63.125 ...
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A8436 Overview The A8436 is a photoflash capacitor charger control IC with adjustable input current limiting. It also integrates an IGBT driver for strobe operation of the flash tube, dramatically saving board space in comparison to discrete solutions for strobe ...
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A8436 Charging Cycles for a Completely Discharged Photoflash Capacitor Figure 4A. Initial two cyles of charging a completely discharged photoflash capacitor. In these two cycles, off-time (V low) is controlled by the internal SW 18 μs timer (Timer mode). Note ...
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A8436 To understand the Timer mode noted that the secondary winding charge current decreases linearly at a rate of: Secondary dI V Secondary OUT = L dt Primary where the secondary side current, Secondary ...
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A8436 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 (V) is the required output voltage level, OUT ...
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A8436 Adjusting Output Voltage The A8436 senses output voltage during switch off-time. This allows the voltage divider network, R1 through R3 (see figure 6 connected at the anode of the high voltage output diode, D1, eliminating power loss ...
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A8436 0.25 1 0.40 10 Photoflash Capacitor Charger with IGBT Driver Package EJ, 10-Contact TDFN/MLP 3.00 0.85 3.00 2 0.75 C PCB Layout Reference View 0.50 All dimensions nominal, not for tooling use 2 (reference JEDEC MO-229WEED) ...
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A8436 3. 0.23 0.50 Copyright ©2005, 2007, Allegro MicroSystems, Inc. The products described here are manufactured under one or more U.S. patents or U.S. patents pending. Allegro MicroSystems, Inc. reserves the right to make, from time ...