LT1942EUF#PBF Linear Technology, LT1942EUF#PBF Datasheet
LT1942EUF#PBF
Specifications of LT1942EUF#PBF
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LT1942EUF#PBF Summary of contents
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... Open LED Protection for LED Driver 24-Lead QFN Package (4mm × 4mm) ■ U APPLICATIO S ■ Poly-Silicon TFT Displays ■ Amorphous Silicon TFT Displays , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. U TYPICAL APPLICATIO 4.2V 2.2µF V 0.22µ ...
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LT1942 ABSOLUTE AXI U RATI GS (Note 1) V Voltage............................................................. 16V CC SW1, SW2, SW3 Voltage .......................... –0.4V to 36V SW4 .......................................................... –0.4V to 45V FB1, FB3 Voltage ................................................... 2.5V FB4 Voltage ....................................................... 400mV NFB2 Voltage ................................................... ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER LED1-LED2 Current Matching LED1 Voltage LED2 Voltage LED1, LED2 Maximum Current LED1, LED2 Leakage Current AV Maximum Duty Cycle DD V Maximum Duty Cycle OFF V Maximum Duty Cycle ON ...
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LT1942 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER PGOOD Leakage Current PGOOD Sink Current CT Charging Current CT Reference Voltage V Leakage Current OUT3 V Source Current OUT3 Minimum D3/V Operating Voltage OUT3 D4 LED Open-Circuit Voltage ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS FB4 Voltage 210 208 206 204 202 200 198 196 194 192 190 –40 – 100 TEMPERATURE (°C) 1942 G04 Quiescent Current 10.0 9.5 9.0 8.5 8.0 7.5 ...
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LT1942 W U TYPICAL PERFOR A CE CHARACTERISTICS LED1 to LED2 Current Matching 2 LED1 LED2 T = 85°C 1.5 A 1.0 0 25° –40°C A –0.5 –1.0 –1.5 ...
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CTIO S PGND23 (Pin 1): Power Ground for V Tie directly to local ground plane. SW3 (Pin 2): Switch Pin for V ON collector of an internal NPN power switch. Minimize the metal trace area ...
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LT1942 CTIO S LED1 (Pin 18): First Input of Current Mirror for an LED String. Connect the negative end of first string of LEDs to this pin. If not in use, leave floating. SW4 (Pin ...
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W BLOCK DIAGRA PGOOD REFERENCE 13 FB1 SHDN ONE 7 SHOT ENABLE –150mV V CC REFERENCE 22 NFB2 6 1MHz OSCILLATOR ENABLE 1.250V REFERENCE CTRL4 ENABLE 8 90k AGND 10 10k 200mV FB4 SS1 11 SOFT-START ...
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LT1942 U OPERATIO Refer to the figure on the first page of this data sheet and the Block Diagram when following the description of the operation of the LT1942. The LT1942 contains four switch- ing regulators. Three switchers are designed ...
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U U APPLICATIO S I FOR ATIO Setting the Output Voltages Unlike charge-pump-based TFT supplies, the LT1942 TFT outputs can all be independently set. The AV V outputs are all inductively based DC/DC converters such, the output voltages ...
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LT1942 U U APPLICATIO S I FOR ATIO SHUTDOWN START I < 1µA Q 5V/DIV V AVDD 5V/DIV V 10V/DIV 10V/DIV 10V/DIV V SHDN 1V/DIV > 1V SHDN AV ENABLED FB1 > (97% OF 1.25V) DD ...
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U U APPLICATIO S I FOR ATIO Layout Hints Proper layout techniques must be followed to achieve advertised performance of the part. Keep all SW and FB traces short and small. There are several power ground pins on the LT1942 ...
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LT1942 U TYPICAL APPLICATIO 4.2V C5 2.2µ 0.22µF ON 10V 16V 2mA R4 10k C2 0.22µF C5 0.1µF 16V 16V R3 L5 47µH V 665k OFF –10V 2mA L2 47µ SHUTDOWN ...
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... SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 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 Package 24-Lead Plastic QFN (4mm × ...
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... DFN Package OUT(MAX 38V 2.8mA, I < 1µA, OUT(MAX 34V 25µA, I < 1µA, OUT(MAX 34V 1.9mA, I < 1µA, OUT(MAX 40V 5mA, I < 16µA, DFN Package OUT(MAX 40V 1.2mA, I < 1µA, OUT(MAX LT/LT 1106 REV B • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2004 1942fb ...