lm2798mm-2.0 National Semiconductor Corporation, lm2798mm-2.0 Datasheet

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... The LM2797/98 also features short-circuit protection over- temperature protection, and soft-start circuitry to prevent excessive inrush currents. The LM2798 has a 400µs turn-on time. The turn-on time of the LM2797 is 100µs. Typical Application Circuit © 2003 National Semiconductor Corporation Features n Output voltage options: ± 2.0V 5%, 1 ...

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... LM2797MM-1.8 1.80V 100µs LM2797MMX-1.8 LM2798MM-1.5 1.50V 400µs LM2798MMX-1.5 LM2798MM-1.8 1.80V 400µs LM2798MMX-1.8 LM2798MM-2.0 2.00V 400µs LM2798MMX-2.0 www.national.com LM2797/98 Mini SO-10 (MSOP-10) Package NS Package #: MUB10A Top View Description Regulated Output Voltage First Flying Capacitor: Negative Terminal First Flying Capicitor: Positive terminal Input Voltage ...

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Absolute Maximum Ratings 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications EN, POK, BATOK pins: Voltage IN to Ground (Note 3) Junction Temperature (T ) J-MAX-ABS Continuous ...

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... D-MAX The ambient temperature operating rating is provided merely for convenience. This part may be operated D-MAX of LM2798MM-1.8 is 1.8V. OUT-NOM being swept in small increments from 3.0V to 4.2V. The average is calculated from these measurement results. IN vs. Time) is not done in computing the average. ...

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Block Diagram 5 20044503 www.national.com ...

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Typical Performance Characteristics o 1.0µ 10µ Capacitors are low-ESR multi-layer ceramic capacitors (MLCC’s). OUT A Output Voltage vs. Input Voltage: LM2798-1.5 (1mA) Output Voltage vs. Input Voltage: LM2797/98-1.8 (1mA) Output Voltage vs. Input Voltage: ...

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Typical Performance Characteristics o 1.0µ 10µ Capacitors are low-ESR multi-layer ceramic capacitors (MLCC’s). (Continued) OUT A Efficiency vs. Input Voltage: LM2798-1.5 Efficiency vs. Input Voltage: LM2797/98-1.8 Efficiency vs. Input Voltage: LM2798-2.0 Unless otherwise specified: ...

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Typical Performance Characteristics o 1.0µ 10µ Capacitors are low-ESR multi-layer ceramic capacitors (MLCC’s). (Continued) OUT A Output Voltage Ripple vs. Output Current Output Voltage Ripple Start Up Waveform: LM2798-1.8 www.national.com Unless otherwise specified: C ...

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Operation Description OVERVIEW The LM2797/98 are switched capacitor converters that pro- duce a regulated low-voltage output. The core of the parts is a highly efficient charge pump that utilizes multiple fractional gains and pulse-frequency modulated (PFM) switching to minimize power ...

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Operation Description The 10mA load curve in Figure 1 gives a clear picture of how base-gain affects overall converter efficiency. The "ideal ef- ficiency gradients" in the figure show the efficiency of ideal switched capacitor converters with gains of 1, ...

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Operation Description TABLE 4. Typical BATOK functionality, with 1MΩ pull-up resistor connected between BATOK and > 2.85V > < 1.1V, 2.65V > 1.1V ≤ 1.1V BATOK: INPUT VOLTAGE STATUS INDICATOR The BATOK pin is an NMOS-open-drain-logic signal ...

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Application Information Capacitors with a Y5V or Z5U temperature characteristic are generally not recommended for use with the LM2797/98. These types of capacitors typically have wide capacitance tolerance (+80%, -20%) and vary significantly over tempera- o ture (Y5V: +22%, -82% ...

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Layout Guidelines Proper board layout to accommodate the LM2797/98 circuit will help to ensure optimal performance. The following guide- lines are recommended: • Place capacitors as close to the LM2797/98 as possible, and preferably on the same side of the ...

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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 ...