A8735 Ultra Small Mobile Phone Xenon Photoflash Capacitor Charger with IGBT Driver Discontinued Product This device is no longer in production. The device should not be purchased for new design applications. Samples are no longer available. Date of status change: December 3, 2013 Recommended Substitutions: For existing customer transition, and for new customers or new appli- cations, contact Allegro Sales. NOTE: For detailed information on purchasing options, contact your local Allegro field applications engineer or sales representative. Allegro MicroSystems, LLC reserves the right to make, from time to time, revisions to the anticipated product life cycle plan for a product to accommodate changes in production capabilities, alternative product availabilities, or market demand. The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, LLC assumes no respon- sibility for its use nor for any infringements of patents or other rights of third parties which may result from its use.A8735 Ultra Small Mobile Phone Xenon Photoflash Capacitor Charger with IGBT Driver Description Features and Benefits Ultra small 2 2 DFN/MLP-8 package The Allegro A8735 is a Xenon photoflash charger IC designed Low quiescent current draw (0.5 A max. in shutdown mode) to meet the needs of ultra low power, small form factor cameras, Primary-side output voltage sensing no resistor divider required particularly camera phones. By using primary-side voltage Fixed 1 A peak current limit sensing, the need for a secondary-side resistive voltage divider 1V logic (V (min)) compatibility HI is eliminated. This has the additional benefit of reducing leakage Integrated IGBT driver with internal gate resistors currents on the secondary side of the transformer. To extend Optimized for mobile phone, 1-cell Li+ battery applications battery life, the A8735 features very low supply current draw Zero-voltage switching for lower loss (0.5 A max in shutdown mode). The IGBT driver also has >75% efficiency internal gate resistors for minimum external component count. Charge complete indication The charge and trigger voltage logic thresholds are set at 1 Integrated 50 V DMOS switch with self-clamping protection V (min) to support applications implementing low-voltage HI control logic. The A8735 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. Package: 8-pin DFN/MLP (suffix EE) It is lead (Pb) free with 100% matte tin leadframe plating. 2 mm 2 mm, 0.60 mm height Not to scale Typical Applications + + Battery Input Battery Input C1 C1 2.3 to 5.5 V 1.5 to 5.5 V COUT COUT 100F 100F VBAT VBAT 315 V 315 V VOUT Detect VOUT Detect SW SW VIN VDRV VIN VDRV Control Control Block Block C2 I sense C2 I sense SW SW VPULLUP VPULLUP 100 k 100 k CHARGE CHARGE DONE DONE DONE DONE V V IN VDRV IN VDRV IGBT Driver IGBT Driver TRIG TRIG IGBT Gate IGBT Gate GATE GATE GND GND (A) (B) Figure 1. Typical applications: (A) with single battery supply and (B) with separate bias supply 8735-DS