LX1995-1CSE中文资料LED Drivers数据手册Microchip规格书

描述 Description

THIS PRODUCT IS END OF LIFEThe LX1995 is a small sized step-up boost converter available in a Tiny TSOT-5 package suitable for driving adjustable boost topologies, which include drivers for white or color LEDs in portable devices. The LX1995 switches at rates up to 2 MHz to allow the use of extremely small inductor and filter capacitor. The LX1995 is available in two versions, 1 and 2, capable of driving 6 or 10 white LEDs, respectively. Designed for maximum efficiency over a wide output power range, the LX1995 is ideal for displays with day and night usage. The LX1995 features a pseudo-hysteretic pulse frequency modulation that promotes improved performance in battery-operated systems by operating with a quiescent supply current <70µA (typical) and a shutdown current of less than 1µA. The input voltage range is from 1.6V to 5.5V thus allowing for a broad selection of battery voltage applications and start-up is guaranteed at 1.6V input. The output current is readily programmed using one external current sense resistor in series with the LEDs. This configuration provides a feedback signal to the FB pin thus maintaining constant output current regardless of varying input voltage and LED forward voltage (VF). Dimming may be accomplished by PWM modulating the shutdown input; the fast response time and stability of the PFM modulation circuit allows PWM dimming to low duty cycles. The LX1995 is available in the 5-Pin TSOT and thus requires a very small PCB area.

特性 Features

·Tiny 5-Pin TSOT Package
·Smallest External Components
·Efficient even at low current levels Logic Controlled Shutdown
·< 1µA Shutdown Current
·> 85% Maximum Efficiency
·70µA Typical Quiescent Supply Current
  ROHS, PB Free