LP3905SD-30EV National Semiconductor, LP3905SD-30EV Datasheet
LP3905SD-30EV
Specifications of LP3905SD-30EV
Related parts for LP3905SD-30EV
LP3905SD-30EV Summary of contents
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... Baseband Processors n Peripheral Processor (Video, Audio) n I/O Power n FPGA Power Typical Application Circuit FIGURE 1. Typical Application Circuit – 14 Pin LLP Package © 2006 National Semiconductor Corporation Key Specifications Buck Regulators n Fixed and adjustable voltage options, range 1. 90% Efficiency n Auto-switching PFM-PWM mode and fixed PWM mode ...
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Block Diagram Connection Diagram www.national.com FIGURE 2. Simplified Functional Diagram FIGURE 3. 14 Pin LLP Package 2 20152902 20152907 ...
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... FIGURE 4. LP3905 14 Pin LLP Package Marking NS package number SDA14B Order Number Package Marking 2.8 LP3905SD-00 LP3905SDX-00 2.8 LP3905SD-30 LP3905SDX-30 2.8 LP3905SD-A3 LP3905SDX-A3 3 Supplied As 1000 units, Tape-and-Reel 3905-00 4500 units, Tape-and-Reel 1000 units, Tape-and-Reel 3905-30 4500 units, Tape-and-Reel 1000 units, Tape-and-Reel 3905-A3 4500 units, Tape-and-Reel www ...
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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 FB1, FB2, EN1,EN2 Continuous Power Dissipation (Note 3) Junction Temperature (T ) J-MAX Storage Temperature Range Maximum Lead Temperature (Soldering, 10 sec.) ESD Rating (Note 4) ...
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General Electrical Characteristics Buck Regulator Electrical Characteristics Buck 1 & 2 have a current rating Vnom1 , V = Vnom2 and C (Buck1) OUT(Buck2) type apply over the full junction temperature range (−40˚C ≤ T LP3905 Typical ...
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General Electrical Characteristics LDO Regulator Electrical Characteristics The linear regulators have a current rating of I Unless otherwise specified, limits are set with V = 25˚C. Limits in boldface type apply over the full junction temperature range (−40˚C ≤ T ...
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Typical Application Circuit FIGURE 5. Typical Application Circuit For Adjustable Device Functional Description POWER UP/DOWN PROCEDURE The LP3905 Bucks and LDOs are powered UP/DOWN with 2 control pins, EN1 and EN2. In order for the enable pins to operate, V ...
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Functional Description DC/DC BUCK REGULATORS The LP3905 Buck regulators are high efficiency step down DC-DC switching converters used for delivering a constant voltage from either a single Li-Ion or three cell NiMH/NiCd battery to portable devices such as cell phones ...
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Functional Description rectifier at the SW pin to a low-pass filter formed by the inductor and output filter capacitor. The output voltage is equal to the average voltage at the SW pin. PWM OPERATION During PWM operation the converters operate ...
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Functional Description the cycle repeats to restore the output voltage (average voltage in pfm mode) to ∼1.15% above the nominal PWM output voltage. If the load current should increase during PFM mode caus- ing the output voltage to fall below ...
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Application Information DC/DC CONVERTORS Adjustable Buck - Output Voltage Selection The buck converter output voltage of the adjustable version device can be set via the selection of the external feedback resistor network forming the output feedback between the output voltage ...
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Application Information Buck DC/DC Convertor Input Capacitor Selection A ceramic input capacitor of 10µF, 6.3V is sufficient for most applications. Place the input capacitor as close as possible to the V pin of the device. A larger value may be ...
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Application Information The ceramic capacitor’s capacitance can vary with tempera- ture. The capacitor type X7R, which operates over a tem- perature range of -55˚C to +125˚C, will only vary the capaci- ± tance to within 15%. The capacitor type X5R ...
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LP3905 Board Layout Considerations PC board layout is an important part of DC-DC converter design. Poor board layout can disrupt the performance of a DC-DC converter and surrounding circuitry by contributing to EMI, ground bounce, and resistive voltage loss in ...
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