LT1947EMS Linear Technology, LT1947EMS Datasheet
LT1947EMS
Specifications of LT1947EMS
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LT1947EMS Summary of contents
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... The device operates from an input range of 2. and is available in 10-lead MSOP and thermally enhanced 10-lead MSOP packages. , LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners OFF – ...
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... PLASTIC MSOP T JMAX LTBQW The ● denotes the specifications which apply over the full operating = 25° 3.3V SHDN = 2. ORDER PART NUMBER TOP VIEW LT1947EMS SHDN 7 SW2 PART MARKING = 125°C, θ = 120°C/W JA LTUE = 3.3V unless otherwise specified. MIN TYP 2 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL CONDITIONS Error Amplifier Voltage Gain EA1 and EA2 C Current Source V T FB1 C Threshold to Turn FB1 Voltage to Begin C Charge T SW1 Current ...
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LT1947 W U TYPICAL PERFOR A CE CHARACTERISTICS SW1 Current Limit 1.8 1.6 1.4 1.2 1.0 0.8 –50 – TEMPERATURE (°C) Switch 1 Saturation Voltage 500 400 25°C 300 90°C 200 –45°C 100 0 0 0.2 0.4 0.6 ...
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CTIO S FB1 (Pin 1): Feedback Pin for First Switcher. Connect resistor divider tap here. Set 1.26V(1 + R1/R2). DD FB2 (Pin 2): Feedback Pin for Second Switcher. Connect resistor divider 2 ...
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LT1947 W BLOCK DIAGRA – REF V O2 OSC 1.26V REFERENCE 3MHz AND SLOPE 1 OSCILLATOR UNDERVOLTAGE SLOPE 2 LOCKOUT 6 – FB1 5.5µA 28mV + – + – REF + REF – ...
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U OPERATIO To best understand operation of the LT1947, please refer to the LT1947 Block Diagram. The device contains two switching regulators, a timer and a high side switch. Three outputs can be generated: an adjustable AV charge-pumped inversion of ...
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LT1947 U OPERATIO V 2.2µF CERAMIC R SS 33. 33nF C1: TAIYO YUDEN LMK316BJ225MD C2: TAIYO YUDEN LMK325BJ335MD ×2 C3: AVX 0.22µF 25V X7R C4, C6: TAIYO YUDEN LMK107BJ684MA 5V/DIV 20V/DIV AV 10V/DIV 10V/DIV 8 D3 ...
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U TYPICAL APPLICATIO 3.3V C1 4.7µF SHUTDOWN C1: TAIYO YUDEN JMK316BJ475MD 4.7µF 6.3V X7R C2: TAIYO YUDEN LMK325BJ335MD 3.3µF 10V X7R ×2 C3: AVX 0.22µF 25V X7R C4, C6: TAIYO YUDEN LMK107BJ684MA 0.68µF 10V X7R V IN ...
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LT1947 PACKAGE DESCRIPTIO 5.23 (.206) MIN 0.305 ± 0.038 (.0120 ± .0015) TYP RECOMMENDED SOLDER PAD LAYOUT 0.254 (.010) GAUGE PLANE 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, ...
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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 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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... MS10 OUT Q SHDN Max = 6V 38µ <1µA, MS10 OUT Q SHDN Max = 6V 38µ <1µA, MS10 OUT Q SHDN Max = 6V 38µ <1µA, MS10 OUT Q SHDN LT/LT 0605 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2001 1947fa ...