LM1937SF5 HTC [HTC Korea TAEJIN Technology Co.], LM1937SF5 Datasheet
LM1937SF5
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LM1937SF5 Summary of contents
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... The output capacitor can be as small as 0.22µF, saving space versus alternative solutions. A low 95mV feedback voltage minimizes power loss for better efficiency. TYPICAL APPLICATION CIRCUIT Jul. 2010 - Rev. 1.1.1 Figure 1. Li-Ion Powered Driver for Three White LEDs - 1 - LM1937 SOT-23 5L (SOT-25) 1.SW 2.GND 3.FB 4.SHDN 5.VIN ORDERING INFORMATION Device Marking Package LM1937SF5 1937 SOT-23 5L HTC ...
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WHITE LED STEP-UP CONVERTER PIN DESCRIPTION BLOCK DIAGRAM ABSOLUTE MAXIMUM RATING Input Voltage (Vin) SW Voltage FB Voltage Voltage SHDN Operating Temperature (Topr) Maximum Junction Temperature Storage Temperature (Tstg) Lead Temperature (soldering, 5 sec) (Note ...
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WHITE LED STEP-UP CONVERTER SHDN SHDN SHDN OPERATION The LM1937 uses a constant frequency, current mode control scheme to provide excellent line and load regulation. Operation can be best understood by referring to the block diagram in Figure 2. At ...
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WHITE LED STEP-UP CONVERTER APPLICATIONS INFORMATION Inductor Selection A 22mH inductor is recommended for most LM1937 applications. Although small size and high efficiency are major concerns, the inductor should have low core losses at 1.2MHz and low DCR (copper wire ...
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WHITE LED STEP-UP CONVERTER LED Current Control The LED current is controlled by the feedback resistor (R1 in Figure 1). The feedback reference is 95mV. The LED current is 95mV/R1. In order to have accurate LED current, precision resistors are ...
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WHITE LED STEP-UP CONVERTER Figure 6. Dimming Control Using a Filtered PWM Signal - 6 - LM1937 HTC ...