A8739中文资料Ultra Small Mobile Phone Xenon Photoflash Capacitor Charger with IGBT Driver数据手册Allegro规格书

描述 Description

These parts are discontinued.  Samples are no longer available. For new customers or new applications, please contact Allegro. Date of status change: December 2, 2013.

The Allegro® A8739 is a Xenon photoflash charger IC designed to provide an ultra-small solution with flexibility to adjust both charging current limit and output voltage target. By using primary-side voltage sensing, the need for a secondary-side resistive voltage divider is eliminated. This has the additional benefit of reducing leakage currents on the secondary side of the transformer. Target output voltage is primarily determined by the transformer turns ratio, but it can be further adjusted (in steps of –5 V each) using an external resistor. This enables better output accuracy, as well as greater flexibility in the selection of transformers.

To extend battery life, the A8739 features very low supply current draw (0.5 µA max in shutdown mode and 10 µA in standby mode). The switch current limit can be programmed from 0.45 to 1.5 A in 16 steps with single wire interface, through the CHARGE pin.

The IGBT driver also has internal gate resistors for minimum external component count. The charge and trigger voltage logic thresholds are set at 1 VHI(min) to support applications implementing low-voltage control logic.

The A8739 is available in an 8-contact 2 mm × 2 mm DFN/MLP package with a 0.60 maximum overall package height, and an exposed pad for enhanced thermal performance. It is lead (Pb) free with 100% matte tin leadframe plating.

特性 Features

• Primary-side output voltage sensing; no resistor divider required
• Adjustable switch peak current limit up to 1.5 A with single-wire programming through the CHARGE pin
• Option to fine-tune target voltage
• Ultra-small 2 × 2 DFN/MLP-8 package
• Integrated IGBT driver with internal gate resistors
• Low quiescent current draw (0.5 µA max. in shutdown mode)
• 1 V logic (VHI(min)) compatibility
• Zero-voltage switching for lower loss
• >75% efficiency
• Charge complete indication
• Integrated 50 V DMOS switch

简介

A8739属于集成电路（IC）的电源管理-专用。由制造生产的A8739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。