LT1937ES5 Linear Technology, LT1937ES5 Datasheet
LT1937ES5
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LT1937ES5 Summary of contents
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... Packaging tions. A low 95mV feedback voltage minimizes power loss in the current setting resistor for better efficiency. The LT1937 is available in low profile SC70 and ThinSOT packages. , LTC and LT are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. C2 0.22 F 15mA R1 6 ...
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... Extended Commercial Operating Temperature Range (Note 2)... – Maximum Junction Temperature .......................... 125 C Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 ORDER PART NUMBER LT1937ES5 SW 1 GND PART MARKING 6-LEAD PLASTIC SC70 LTYN T = 125 C, JMAX = 150 C ON BOARD OVER GROUND PLANE ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Quiescent Current 2.2 –50 C 2.0 1.8 100 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0 (V) IN 1937 G01 Feedback Bias ...
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LT1937 W BLOCK DIAGRA (PIN 6 FOR 5 3 SC70 PACKAGE) 95mV V REF 1.25V SHDN 4 SHUTDOWN U OPERATIO The LT1937 uses a constant frequency, current mode control scheme to provide excellent line and load regula- ...
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U U APPLICATIO S I FOR ATIO Inductor Selection inductor is recommended for most LT1937 appli- cations. Although small size and high efficiency are major concerns, the inductor should have low core losses at 1.2MHz and low ...
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LT1937 U U APPLICATIO S I FOR ATIO 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 ...
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U U APPLICATIO S I FOR ATIO 2. Using a DC Voltage For some applications, the preferred method of brightness control is a variable DC voltage to adjust the LED current. The dimming control using a DC voltage is shown ...
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LT1937 U U APPLICATIO S I FOR ATIO D1 2.2nF R2 D2 LT1937 D2: MMBT (11a) Recommended Soft-Startup Circuit Figure 11. Recommended Soft-Startup Circuit and Waveforms Board Layout Consideration As with all switching regulators, careful attention must ...
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U TYPICAL APPLICATIO S Li-Ion to Two White LEDs DIMMING LT1937 SHDN FB GND C : TAIYO YUDEN JMK107BJ105 ...
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LT1937 U U TYPICAL APPLICATIO S TYPICAL APPLICATIO S Li-Ion to Five White LEDs DIMMING 90k LT1937 SHDN FB GND C : ...
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... DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... No Inductor Required, Digital Brightness Adjust, MS8 Package www.linear.com C OUT 0. 1937 TA02a Switching Waveforms 1937 TA02c = 3.6V 0.2 s/DIV V IN FOUR LEDs 15mA , 15V 10V, Drives Up to Eight LEDs from 3V Input, IN LT/TP 0702 2K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2002 , OUT Q 1937f ...