LD7850

LD7850 3/18/2010 High Voltage Step-Down White LED Driver REV: 00a General Description The LD7850 is a step-down DC/DC converter, especially designed to drive power white LEDs with constant current. With capability to transfer output voltage up to 60V, the LD7850 can drive a string of up to 15 series-connected power white LEDs and ensure uniform brightness. To optimize the efficiency, the feedback voltage is set to 0.4V. This reduces the power dispassion on the current sense resistor. The other features include under-voltage lockout, over-current protection and dimming function essential for the white LED applications. LD7850 is available in a space saving MSOP-10 and SOP-8 package. +patent pending Features ‧ Input Voltage Range: 12V to 70V ‧ Hysteresis Mode Control ‧ Drive one string of LEDs, VO up to 60V ‧ No need output capacitor ‧ Analog Dimming Control ‧ Over Current Protection ‧ Suspend current < 1.5mA Applications ‧ Electronic Appliances ‧ Automotive LED Driver Application ‧ Bracket Lamp and Wall Lamp Application Typical Application Fig. 1 Application circuit 1 Leadtrend Technology Corporation LD7850-DS-00a March 2010 www.leadtrend.com.tw LD7850 3/18/2010 Pin Configuration SOP-8 (EP) (TOP VIEW ) PHASE GATE GND MSOP-10 (TOP VIEW) PHASE PGND GATE GND 7 FB 8 7 6 5 10 9 8 TOP MARK YYWWPP 1 2 3 4 1 TOP MARK YYWWPP 2 3 4 5 FB 6 YY: Year code WW: Week code PP: Production code VDD BOOT VCC BOOT VCC EN EN Ordering Information Part number LD7850 GSE L...