PAM2845
PAM2845 is 40V High Power Boost Convertor manufactured by Power Analog Micoelectronics.
40V High Power Boost Convertor with 6 Channel Constant Current Source Features n Six Constant-Current Output Channels n Parallel Channels Allow Higher Current per LED String n Maximum 40V Continuous Voltage Output Limit for Each Channel n Adjustable Constant Output Voltage n Adjustable Constant LED Current n Drives 10 or more LEDs Each String as Long as the String Voltage Less Than 40V n Internal 2.5A Power MOSFET n Allows Digital PWM and Analog Dimming n Wide (100:1) PWM Dimming Range without Color Shift n Independent Dimming and Shutdown Control of the LED Driver n ±1% Typical Current Matching between Strings n Short LED Protection n 3 Frequencies Selection: 1.6MHz/1MHz/500k Hz n Wide Input Voltage Range: 4.8V to 28V n Over Temperature Protection n Available in 24-pin 4mmx4mm QFN Package n Pb-free Package
Description
The PAM2845 is a high-efficiency boost type LED driver. It is designed for large LCD panel that employs an array of LEDs as back light source. The PAM2845 employs a current-mode step-up converter that drives six parallel strings of LEDs connected in multiple series. This built-in stringcurrent-control circuit achieves ±1% typical current matching between strings, which ensures even brightness for all LEDs. Separate feedback loops limit the output voltage if one or more LEDs open or short. The PAM2845 has Features cycle-by-cycle current limit to provide consistent operation and soft-start capability. A thermal-shutdown circuit provides another level of protection. The PAM2845 has a wide +4.8V to +28V inputvoltage range and provides adjustable full-scale LED current. The switching frequency of this device can be selected among 500k Hz, 1MHz and 1.6MHz according to the application requirements.
Applications n White or RGB Backlighting for LCD TV, LCD Monitor, Notebook, Handy Terminals, and Avionics Displays Panels n LED Lighting Devices
Typical Application
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VIN: 4.8V to 28V 10 μ F
22 μ H
3A/40V
L SW SW SW FB R2
10 μ...