SD42522 Silan, SD42522 Datasheet
SD42522
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SD42522 Summary of contents
Page 1
... High Power LED Driver with 6～36V Input DESCRIPTION The SD42522 is a step-down PWM control LED driver with a built-in power MOSFET. It achieves 1A continuous output current in 6~36V input voltage range. It provides thermal shutdown circuit, current limit circuit. The SD42522 adopts current mode control which provides fast transient response and simple loop stabilization design ...
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... SENSE voltage Junction Temperature Lead Temperature Storage Temperature Input Voltage Operating Temperature ELECTRICAL CHARACTERISTICS Characteristics Supply Voltage Operating Current Upper Switch Leakage Current Limit Maximum Duty Cycle Oscillator Frequency HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http://www.silan.com.cn Symbol Ratings -1 COMP V -0.3~VIN SENSE ...
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... NC FUNCTION DESCRIPTION The SD42522 is a current mode LED driver. The voltage on compensation pin COMP is proportional to the current delivered to the load. At the beginning of a cycle: the upper transistor M1 is off; the COMP pin voltage is higher than the current sense amplifier output; and the current comparator’s output is low. The rising edge of the 280KHz CLK signal sets the RS Flip-Flop whose output turns on M1 thus VIN, Rs, LED, inductor and M1 comprises a circuit loop and the inductor current increases ...
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... VSENSE(Drop voltage on Rs) is 88mV, and adjust the output current by adjusting the sampling resistor Rs (refer to Typical Application Circuit). 2. Current limiting SD42522 has internal current limiting function, and the voltage on COMP is clamped at about 1.9V, the output current of the power MOSFET is limited at about 1.9A by current comparator. 3. Frequency jitter SD42522 has internal frequency jitter function to improve the EMI performance of the system ...
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... Diode Selection SD42522 is a non-synchronous step-down adjuster, so the diode should provide continuous current when the power MOSFET is off. Because the forward voltage of Schottky diode is small, and the reverse continuous current time is short usually used for continuous current. During the power MOSFET is conducting, the diode will withstand high voltage, so the reverse voltage of selected diode should be bigger than the input voltage ...
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... TYPICAL APPLICATION CIRCUIT Note: The circuit and parameters are reference only, please set the parameters of the real application circuit based on the real test . www.DataSheet4U.com HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http://www.silan.com.cn 6～36V input voltage, 350mA output LED driver REV:1.0 2009.07.06 Page ...
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... Output 700mA efficiency changed following the input voltage Output current change curve when input voltage is close to output voltage(350mA) HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http://www.silan.com.cn Output 350mA current change rate following the input voltage change Output 700mA current change rate following ...
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... MOS devices should be packed for dispatch in antistatic/conductive containers. Disclaimer: • Silan reserves the right to make changes to the information herein for the improvement of the design and performance without further notice! • All semiconductor products malfunction or fail with some probability under special conditions. When using Silan products ...