a8438eej-t Allegro MicroSystems, Inc., a8438eej-t Datasheet
a8438eej-t
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a8438eej-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: 1.6, 1.8, 2.0 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 A8438EEJTR-T *Contact Allegro for additional packing options Absolute Maximum Ratings Characteristic SW pin IGBTDRV pin FB pin All other pins ...
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... Output voltage feedback 10 ILIM Switch current limit setting; sets three discreet levels SW Control Logic 40 V DMOS Q SET CLR SET CMP1 CLR 1.2 V One-Shot Function Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 3 ...
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... V – 3.3 V – 3.3 V – 3.3 V – IN Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com Typ. Max. Units – 5 – μA 0.01 1 μA 1.6 – A 1.8 2 ...
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... D ¯ ¯ O ¯ ¯ N ¯ ¯ E ¯ goes low, to signal the OUT is below V IN goes above V , another low-to-high transition at the CHARGE pin is UVLO above the V level. IN UVLO level when CHARGE goes high. UVLO Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 5 ...
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... 200 Value 2.5 V 3.3 V 100 μ 200 Value 3.0 V 3.3 V 100 μ OUT I BATT t V OUT I BATT t V OUT I BATT t Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 6 ...
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... V 3.3 V 100 μ 200 Value 4 100 μ 200 Value 5.0 V 3.3 V 100 μ OUT I BATT t V OUT I BATT t V OUT I BATT t Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 7 ...
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... Photoflash Capacitor Charger with IGBT Driver Performance Characteristics 50 V 200 Value 2 770 mA 1.8 A 140 μ 200 Value 2.0 V 3.3 V 820 mA 2 140 μ OUT I BATT t V OUT I BATT t Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 8 ...
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... IGBT Drive Timing Definition 50% 50 90% 10% Efficiency T = 25° 3 5.0 V BATT BATT 3.3 V BATT IN 150 200 250 V (V) OUT 90% 10% Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com = 5 300 9 ...
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... LOAD R 12 Ω gate Photoflash Capacitor Charger with IGBT Driver IGBT Drive Performance IGBTDRV V TRIGGER IGBTDRV V TRIGGER t Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 10 ...
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... Figure 3. Sequencing of Timer mode and Fast Charging mode (time axis scale per division only partially discharged. In Fast Charging OUT , is less than approximately Timer OUT Fast Charging Mode Timer Mode Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 11 ...
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... I , can be set to three levels by SWLIM Setting ILIM Pin (A) Connection 1.6 External ground 1.8 Float Pull supply voltage 2.0 with kΩ resistor may be adjusted during charging. SWLIM Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 12 ...
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... X5R or X7R Fairchild Semiconductor BAV23S D1 (dual diode connected in series) TDK LDT565630T-041 4.7 μ 10.2 Primary R1, R2 1206 resistors 0603 resistor R4, R5 Pull-up resistors R6, R7 Pull-down resistors Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com (3) The trans- 13 ...
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... Murata Taiyo Yuden Chemi-Con Philips Semiconductor, Fairchild Semiconductor Vishay Yageo Yageo Asatech TDK TDK Tokyo Coil Engineering Tokyo Coil Engineering Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com (5) (6) , for the ¯ D ¯ ¯ O ¯ 14 ...
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... Allegro products are not authorized for use as critical components in life-support devices or sys tems without express written approval. The in for ma tion in clud ed herein is believed rate and reliable. How ev er, Allegro MicroSystems, Inc. assumes no re spon si bil i ty for its use; ...