A8732: Ultra Small Mobile Phone Xenon Photoflash Capacitor Charger with IGBT Driver

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^®A8732 is a Xenon photoflash charger IC designed to meet the needs of ultra low power, small form factor cameras, particularly camera phones. 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. To extend battery life, the A8732 features very low supply current draw (0.5 μA max in shutdown 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 V_嗨(min) to support applications implementing low-voltage control logic.

The A8732 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.

• 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
• Adjustable switch peak current limit up to 1.5 A with single-wire programming through the CHARGE pin
• 1V logic (V_嗨(min)) compatibility
• Integrated IGBT driver with internal gate resistors
• Optimized for mobile phone, 1-cell Li+ battery applications
• Zero-voltage switching for lower loss
• >75% efficiency
• Charge complete indication
• Integrated 50 V DMOS switch with self-clamping protection