A8739 Ultra-Small Mobile Adjustable 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.A8739 Ultra-Small Mobile Adjustable Xenon Photoflash Capacitor Charger with IGBT Driver Features and Benefits Description Primary-side output voltage sensing no resistor divider required The Allegro A8739 is a Xenon photoflash charger IC designed Adjustable switch peak current limit up to 1.5 A with to provide an ultra-small solution with flexibility to adjust single-wire programming through the CHARGE pin both charging current limit and output voltage target. By using Option to fine-tune target voltage primary-side voltage sensing, the need for a secondary-side Ultra-small 2 2 DFN/MLP-8 package resistive voltage divider is eliminated. This has the additional Integrated IGBT driver with internal gate resistors benefit of reducing leakage currents on the secondary side of Low quiescent current draw (0.5 A max. in shutdown mode) the transformer. Target output voltage is primarily determined 1V logic (V (min)) compatibility HI by the transformer turns ratio, but it can be further adjusted (in Zero-voltage switching for lower loss steps of 5 V each) using an external resistor. This enables better >75% efficiency output accuracy, as well as greater flexibility in the selection of Charge complete indication transformers. Integrated 50 V DMOS switch To extend battery life, the A8739 features very low supply current draw (0.5 A max in shutdown mode and 10 A in standby mode). The switch current limit can be programmed from 0.45 to 1.5 A in 16 steps with single wire interface, Package: 8-pin DFN/MLP (suffix EE) 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 (min) to support applications HI implementing low-voltage control logic. The A8739 is available in an 8-contact 2 mm 2 mm 2 mm 2 mm, 0.60 mm height DFN/MLP package with a 0.60 maximum overall package height, and an exposed pad for enhanced thermal performance. Not to scale It is lead (Pb) free with 100% matte tin leadframe plating. Typical Applications Battery Input Battery Input 2.3 to 5.5 V 2.0 to 5.5 V + + C1 C1 R R BAT BAT COUT COUT 100F 100F VBAT VBAT 315 V 315 V VOUT Detect VOUT Detect SW SW VIN VDRV VIN VDRV Control Control 2.3 to 5.5 V 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 8739-DS