LM1771EVAL National Semiconductor, LM1771EVAL Datasheet
LM1771EVAL
Specifications of LM1771EVAL
Related parts for LM1771EVAL
LM1771EVAL Summary of contents
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... Three versions of the LM1771 are available depending on the switching frequency desired for the application. Nominal switching frequencies are in the range of 100kHz to 1000kHz. Typical Application Circuit © 2006 National Semiconductor Corporation Features n Input voltage range of 2.8V to 5.5V n 0.8V reference voltage n Precision enable ...
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Connection Diagrams Top View 6-Lead LLP (3mm x 3mm) NS Package Number SDE06A Ordering Information Order Number Timing Option LM1771SSD 500ns LM1771SSDX LM1771TSD 1000ns LM1771TSDX LM1771USD 2000ns LM1771USDX Order Number Timing Option LM1771SMM 500ns LM1771SMMX LM1771TMM 1000ns LM1771TMMX LM1771UMM 2000ns ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications EN, FB, HG, LG Storage Temperature Range Electrical Characteristics type apply over the full Junction Temperature Range (−40˚C to +125˚C). Minimum and Maximum limits are guaranteed through test, design or statistical correlation ...
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Typical Performance Characteristics plication circuit shown in Application Information section of this datasheet (LM1771S (LM1771U Temperature (LM1771T) ON www.national.com All curves taken at VIN = 3.3V with ...
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Typical Performance Characteristics application circuit shown in Application Information section of this datasheet. T specified. (Continued Temperature (LM1771S) OFF T vs Temperature (LM1771U) OFF V Threshold vs Temperature EN All curves taken at VIN = 3.3V with configuration ...
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Typical Performance Characteristics application circuit shown in Application Information section of this datasheet. T specified. (Continued) Quiescent Current vs Temperature Efficiency vs I (LM1771T) OUT ( 1.8V OUT Efficiency vs I (LM1771U) OUT (V ...
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Block Diagram 7 20189019 www.national.com ...
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Application Information THEORY OF APPLICATION The LM1771 synchronous buck controller has a control scheme that is referred to as adaptive on-time control. This topology relies on a fixed switch on-time to regulate the output voltage. This on-time is internally set ...
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Application Information the part will be placed into a shutdown state and the drivers will be tri-stated. This allows the LM1771 to be easily se- quenced using a resistive divider from the output of another regulator, or the working input ...
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Design Guide (Continued) peak-to-peak ripple current equal to 30% of the maximum load current. The inductor current ripple ( I lated by: Therefore, L can be initially set to the following by applying the 30% rule: The other features of ...
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Design Guide (Continued) This circuit uses an additional resistor in series with the inductor to add ripple at the output placed in this location and used in combination with the feed-forward capacitor ( provide ripple to ...
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Design Guide (Continued capacitor is recommended as it improves the regu- FF lation and stability of the design. However, its benefit is diminished as V starts approaching V OUT not needed in this situation. INPUT CAPACITOR The ...
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MOSFET Selection (Continued) It can be seen that the average output voltage ( higher than the output voltage (V TUAL calculated by the earlier equation by exactly half the output voltage ripple. The output voltage that is targeted ...
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Layout The LM1771, like all switching regulators, requires careful attention to layout to ensure optimal performance. The fol- lowing steps should be taken to aid in the layout. For more information refer to Application Note AN-1299. 1. Ensure that the ...
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... MSS7341-332NLB = 500kHz Part Number LM1771U Si9433BDY Si4894DY GRM43SR60J107ME20B NOSD157M006R0070 CRCW08052942F CRCW08051002F VJ0805102KXXA DO3316P-222 15 20189043 = 2A) OUT Quantity Vendor 1 National Semiconductor 1 Siliconix 1 Siliconix 1 Murata 1 AVX 1 Vishay 1 Vishay 1 Vishay 1 Coilcraft = 5A) OUT Quantity Vendor 1 National Semiconductor 1 Siliconix 1 Siliconix 1 Murata 1 AVX 1 Vishay 1 Vishay 1 Vishay 1 Coilcraft www.national.com ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted LLP-6 Package NS Package Number SDE06A MSOP-8 Package NS Package Number MUA08A 16 ...
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