The IS31LT3948 is a PFM step-up DC-DC converter designed for driving the white LED arrays for large size LCD panel backlighting applications. It can deliver stable constant output current from a few milliamps up to 2A, programmed via an external resistor. The IS31LT3948 utilizes a control scheme in which the output is automatically adjusted to the optimum output voltage for the system, maximizing the efficiency. Furthermore, the control scheme is inherently stable removing the need to provide additional loop compensation. The device features external PWM dimming, which allows the flexible control of the back-lighting luminance. IS31LT3948 has a wide input voltage range from 5V to 100V. An integrated OVP circuit protects the chip and the system even under no-load conditions. The chip is assembled in SOP-8 package. It operates from 5V to 100V over two temperature ranges of -40°C to +85°C and -40°C to +125°C.
Wide input voltage range: 5V to 100V
Constant current output limited only by externalcomponent selection
No loop compensation required
Internal over-voltage protection
Internal over-temperature protection
Operating temperature range -40°C to +85°C(IS31LT3948-GRLS2-TR)
Operating temperature range -40°C to +125°C(IS31LT3948-GRLS4-TR)