Description
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.
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
▪ Adjustable switch peak current limit up to 1.5 A with
single-wire programming through the CHARGE pin
▪ 1V logic (VHI(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