LP2975AIMM-12 National Semiconductor, LP2975AIMM-12 Datasheet
LP2975AIMM-12
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LP2975AIMM-12 Summary of contents
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... Block Diagram *R values are: 208k for 12V part, 72.8k for 5V part, and 39.9k for 3.3V SET part. © 1999 National Semiconductor Corporation DS100034 Features n Simple to use, few external components n Ultra-small mini SO-8 package n 1.5% (A grade) precision output voltage n Low-power shutdown input < ...
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... LP2975AIMM-5.0 5.0 STD LP2975IMMX-5.0 5.0 STD 3.3 A LP2975AIMMX-3.3 3.3 A LP2975AIMM-3.3 3.3 STD LP2975IMMX-3.3 3.3 STD www.national.com Package Marking L47A LP2975AIMM-12 L47A LP2975IMMX-12 L47B LP2975IMM-12 L47B L46A L46A L46B LP2975IMM-5.0 L46B L45A L45A L45B LP2975IMM-3.3 L45B 2 Supplied As: 3.5k Units on Tape and Reel 250 Units on Tape and Reel 3.5k Units on Tape and Reel 250 Units on Tape and Reel 3 ...
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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. Storage Temperature Range Operating Junction Temperature Range Lead Temp. (Soldering, 5 seconds) ESD Rating Power Dissipation (Note 2) Electrical Characteristics Limits in standard typeface are for T = 25˚ ...
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Electrical Characteristics Note 3: Limits are 100% production tested at 25˚C. Limits over the operating temperature range are guaranteed through correlation using Statistical Quality Control (SQC) methods. The limits are used to calculate National’s Average Outgoing Quality Level (AOQL). Typical ...
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Typical Performance Characteristics is tied to 1.5V. Minimum Operating Voltage DS100034-5 ON/OFF Threshold DS100034-7 ON/OFF Pin Current DS100034-9 Unless otherwise specified 25˚ Referred Gate Clamp Voltage IN Current Limit Sense Voltage Supply Current DS100034-10 ...
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Typical Performance Characteristics is tied to 1.5V. (Continued) ON/OFF Input Resistance Gate-Ground Saturation Load Regulation www.national.com Unless otherwise specified: T Gate Current DS100034-11 Line Regulation DS100034-13 Leakage Current DS100034- 25˚ µF, ON/OFF pin A IN ...
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Typical Performance Characteristics is tied to 1.5V. (Continued) Controller Gain and Phase Response Reference Designs The LP2975 controller can be used with virtually any P-channel MOSFET to build a wide variety of linear voltage regulators. Since it would be impossible ...
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Reference Designs (Continued) Transient Response for 0–5A Load Step DESIGN # 0.5A (Refer to Typical OUT Application Circuits, Adjustable Voltage Regulator) COMPONENTS µF Tantalum µF Tantalum ...
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Reference Designs (Continued) photo below). The total overshoot increases from − about −75 mV, and the second “ring” on the transient is no- ticeably larger. Transient Response with Output Capacitor Halved The design is next tested with only ...
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Reference Designs (Continued) Transient Response for 0–6A Load Step Application Hints SELECTING THE FET The best choice of FET for a specific application will depend on a number of factors: VOLTAGE RATING: The FET must have a Drain-to-Source breakdown voltage ...
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Application Hints (Continued) FET in low power designs. Because of the increased cell density (and tiny packages) used by modern FET’s, the cur- rent carrying capability may easily exceed the power dissipa- tion limits of the package possible ...
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Application Hints (Continued) For maximum accuracy, the INPUT and CURRENT LIMIT pins must be Kelvin connected caused by voltage drops along the traces carrying the cur- rent from the input supply to the Source pin of the ...
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Application Hints (Continued (R2 x 24k) / (R2 + 24k follows that the output voltage will be 1. OUT EQ Some important considerations for an adjustable design: ...
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Application Hints (Continued) As can be seen in the graph, values of C 500 pF–2500 pF range produce values for f 40 kHz and 700 kHz. To determine what effect f on stability, the bandwidth of the regulator loop must ...
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Application Hints (Continued) that when the total phase shift reaches (or gets close to) −180˚, oscillations will result. Therefore, it can be seen that at least two poles in the gain curve are required to cause instability. ...
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Application Hints (Continued) Improved Phase Margin with Feed-Forward To estimate the total phase margin, the individual phase shift contributions of each pole and zero will be calculated assum- = 200 Hz kHz kHz, f ...
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Application Hints (Continued) Low ESR Unstable without Feed-Forward DS100034-30 This application can also be improved by adding a feed- forward capacitor. C will add both a zero the gain plot (see graph LOW ESR CORRECTED WITH FEED-FORWARD ...
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Application Hints (Continued) 1) Calculate the required value of capacitance for C that the pole f 200 Hz (see previous section OUTPUT CA- p PACITOR ). For this calculation, an ESR of about 0.1 be assumed for the purpose of ...
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... NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant ...