A8438中文资料Photoflash Capacitor Charger with IGBT Driver数据手册Allegro规格书

描述 Description

This part is discontinued. Samples are no longer available.

Date of status change: 2010.

The A8438 is a highly integrated IC that charges photoflash capacitors for digital and film cameras. It also features an integrated IGBT driver that facilitates the flash discharge function and saves board space.

To charge the photoflash capacitor, the A8438 integrates a 40 V, DMOS switch that drives the transformer in a flyback topology, allowing optimized design with tight coupling and high efficiency. A proprietary control scheme optimizes the capacitor charging time. Low quiescent current and low shutdown current further improve system efficiency and extend battery life.

Three levels of switch current limit are provided: 1.6, 1.8, and 2.0 A. The level is determined by configuring the ILIM pin as grounded, floating, or pulled up to IC supply voltage, respectively.

The CHARGE pin enables the A8438 and starts the charging of the output capacitor. When the designated output voltage is reached, the A8438 stops the charging until the CHARGE pin is toggled again. Pulling the CHARGE pin low stops charging. The DONE pin is an open-drain indicator of when the designated output voltage is reached.

The A8438 can be used with two Alkaline/NiMH/ NiCAD or one single-cell Li+ battery connected to the transformer primary. Connect the VIN pin to a 3.0 to 5.5 V supply, which can be either the system rail or the Li+ battery, if used.

The A8438 is available in a very low profile (0.75 mm) 10-terminal 3×3 mm MLP/TDFN package, making it ideal for space-constrained applications. It is lead (Pb) free, with 100% matte-tin leadframe plating.

The A8438 is part of a product family that includes the A8436 and A8439.

特性 Features

• Power with Alkaline/NiMH/NiCAD or Li+ batteries
• Adjustable output voltage
• >75% efficiency
• Three levels of switch current limit: 1.6, 1.8, 2.0 A
• Fast charge time
• Charge complete indication
• Integrated IGBT driver with trigger
• No primary-side Schottky diode needed
• Low-profile package (0.75 mm nominal height)

简介

A8438属于集成电路（IC）的电源管理-专用。由制造生产的A8438电源管理 - 专用专用型电源管理集成电路 (PMIC) 用于电源的控制或操作，适合特定或小范围的目标应用，例如汽车气囊管理、电容器组平衡、AC 公共电力监控、存储器总线端接、接地故障检测、能量收集、小型引擎管理、处理器或芯片集专用电压调节、负载突降保护、触觉驱动器、热电制冷器控制等。