A8735EEETR-T Allegro Microsystems Inc, A8735EEETR-T Datasheet
A8735EEETR-T
Specifications of A8735EEETR-T
Related parts for A8735EEETR-T
A8735EEETR-T Summary of contents
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Ultra Small Mobile Phone Xenon Photoflash Features and Benefits ▪ Ultra small 2 × 2 DFN/MLP-8 package ▪ Low quiescent current draw (0.5 μA max. in shutdown mode) ▪ Primary-side output voltage sensing; no resistor divider required ▪ Fixed 1 ...
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... A8735 Selection Guide Part Number Packing A8735EEETR-T 3000 pieces per reel Absolute Maximum Ratings Characteristic Symbol V SW Pin VIN_DRV, VBAT Pins CHARGE, TRIG, ¯ D ¯ ¯ O ¯ ¯ N ¯ ¯ E ¯ Pins Remaining Pins Operating Ambient Temperature Maximum Junction T J Storage Temperature ...
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A8735 VBAT V – BAT ILIM Reference V ref DS VIN_DRV CHARGE TRIG Pin-out Diagram DONE 1 8 CHARGE TRIG 2 7 VIN_DRV PAD GATE 3 6 VBAT GND (Top View) Ultra Small Mobile Phone ...
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A8735 ELECTRICAL CHARACTERISTICS guaranteed from −40°C to 85°C ambient, unless otherwise noted Characteristics 1 VBAT Voltage Range 1 VIN_DRV Voltage Range UVLO Enable Threshold UVLO Hysteresis V Supply Current IN VBAT Pin Supply Current Current Limit Primary-Side Current Limit 2 ...
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A8735 VBAT UVLO V IN CHARGE SW Target V V OUT DONE TRIG GATE Explanation of Events A: Start charging by pulling CHARGE to high, provided that V B: Charging stops when V C: Start a new charging process with ...
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A8735 IGBT drive waveforms are measured at pin, with capacitive load of 6800 pF Rising Signal Symbol Parameter Units/Division TRIGGER GATE time 100 ns Conditions Parameter ...
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A8735 Transformer L PRIMARY Transformer L 86% 84% 82% 80% 78% 76% 74% 72% 70% 68% 66% 64% 62% 60% 58% 56% 54% Ultra Small Mobile Phone Xenon Photoflash Capacitor Charger with IGBT Driver ...
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A8735 Transformer L 328 327 326 325 324 323 322 321 320 Note: Output voltage is sensed from the primary side winding when the switch turns off. This duration long enough (>200 ns) in order to obtain ...
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A8735 Output Capacitor Charging at Various Battery Voltages Test conditions 3 100 μF / 330 V UCC, transformer = T-16-024A (L IN OUT Oscilloscope settings: Ch1 = ¯ D ¯ ¯ O ¯ ¯ N ...
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A8735 General Operation Overview The charging operation is started by a low-to-high signal on the CHARGE pin, provided that V is above the V IN strongly recommended to keep the CHARGE pin at logic low during power-up. After V exceeds ...
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A8735 As soon as a sufficient voltage has built up at the output capaci- tor, the IC enters Fast-Charging mode. In this mode, the next switching cycle starts after the secondary side current has stopped flowing, and the switch voltage ...
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A8735 Transformer Design 1. The transformer turns ratio, N, determines the output voltage 31.5 × N – OUT d where 31.5 is the typical value of V OUTTRIP ward drop ...
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A8735 Input Capacitor Selection Ceramic capacitors with X5R or X7R dielectrics are recom- mended for the input capacitor During initial Timer mode IN the device operates with 18 μs off-time. The resonant period caused by input filter inductor ...
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A8735 Layout Guidelines Key to a good layout for the photoflash capacitor charger circuit is to keep the parasitics minimized on the power switch loop (transformer primary side) and the rectifier loop (secondary side). Use short, thick traces for connections ...
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A8735 Recommended layout: C4 Schematic 0.1uF DONE CHARGE Top side Bottom side Top components Ultra Small Mobile Phone Xenon Photoflash Capacitor Charger with IGBT Driver VBAT C2 10uF R10 6 5 A8735 2k VBAT VIN_DRV GATE 1 ...
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A8735 Package EE 8-Contact DFN/MLP with Exposed Thermal Pad D 9X 0.08 C 0.25 ±0.05 0.325 ±0.050 Copyright ©2010, Allegro MicroSystems, Inc. The products described here are manufactured under one or more U.S. patents or U.S. patents pending. Allegro MicroSystems, ...