lm2735xsdx National Semiconductor Corporation, lm2735xsdx Datasheet
lm2735xsdx
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... Tiny SOT23-5, LLP-6, and eMSOP-8 packages provide space-savings. Additional features include internal soft-start, circuitry to reduce inrush current, pulse-by-pulse current limit, and thermal shutdown. Typical Boost Application Circuit © 2007 National Semiconductor Corporation Features ■ Input voltage range 2.7V to 5.5V ■ Output voltage range 3V to 24V ■ ...
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... Top View 20215803 5-Pin SOT23 Ordering Information Order Number Description LM2735YMF LM2735YMFX LM2735YSD 520kHz LM2735YSDX LM2735YMY LM2735YMYX LM2735XMF LM2735XMFX LM2735XSD 1.6MHz LM2735XSDX LM2735XMY LM2735XMYX www.national.com Top View 20215804 6-Pin LLP Package Type Package Drawing SOT23-5 MF05A LLP-6 SDE06A eMSOP-8 MUY08A SOT23-5 MF05A ...
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Pin Description - 5-Pin SOT23 Pin Name Function 1 SW Output switch. Connect to the inductor, output diode. Signal and power ground pin. Place the bottom resistor of the feedback network as close as possible to this 2 GND pin. ...
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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 Voltage FB Voltage EN Voltage ESD Susceptibility (Note 4) Junction Temperature (Note 2) Storage Temp. Range ...
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Symbol Parameter Junction to Ambient θ LFPM Air Flow (Note 3) θ Junction to Case (Note Thermal Shutdown Temperature (Note 2) SD Thermal Shutdown Hysteresis Note 1: Absolute Maximum Ratings indicate limits beyond which damage ...
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Typical Performance Characteristics Current Limit vs Temperature Oscillator Frequency vs Temperature - "X" Typical Maximum Output Current vs V www.national.com FB Pin Voltage vs Temperature 20215806 Oscillator Frequency vs Temperature - "Y" 20215808 R IN DSON 20215810 6 20215807 20215809 ...
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LM2735X Efficiency vs Load Current 20V LM2735X Efficiency vs Load Current 12V Output Voltage Load Regulation LM2735Y Efficiency vs Load Current 20V 20215812 LM2735Y Efficiency vs Load Current 12V 20215814 Output Voltage ...
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Simplified Internal Block Diagram Application Information THEORY OF OPERATION The LM2735 is a constant frequency PWM boost regulator IC that delivers a minimum of 2.1A peak switch current. The reg- ulator has a preset switching frequency of either 520 kHz ...
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FIGURE 3. Typical Waveforms CURRENT LIMIT The LM2735 uses cycle-by-cycle current limiting to protect the internal NMOS switch important to note that this cur- rent limit will not protect the output from excessive current during an output short ...
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One must also ensure that the minimum current limit (2.1A) is not exceeded, so the peak current in the inductor must be calculated. The peak current ( the inductor is calcu- LPK lated by: + Δ ...
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FIGURE 6. LM2735 Without External Compensation One can see that the Crossover frequency is fine, but the phase margin at 0dB is very low (22°). A zero can be placed just above the crossover frequency so that the phase margin ...
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There are miscellaneous poles and zeros associated with parasitics internal to the LM2735, external components, and the PCB. They are located well over the crossover frequency, and for simplicity ...
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Other factors that influence thermal performance are thermal vias, copper weight, and number of board layers. Definitions Heat energy is transferred from regions of high temperature to regions of low temperature via three basic mechanisms: radiation, conduction and ...
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LM2735 Thermal Models Heat is dissipated from the LM2735 and other devices. The external loss elements include the Schottky diode, inductor, www.national.com and loads. All loss elements will mutually increase the heat on the PCB, and therefore increase each other’s ...
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Calculating Efficiency, and Junction Temperature The complete LM2735 DC/DC converter efficiency (η) can be calculated in the following manner. Power loss ( the sum of two types of losses in the LOSS converter, switching and conduction. Conduction losses ...
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The value for should be equal to the resistance at the junction temperature you wish to analyze example, at 125°C = 250 mΩ (See typical graphs for value). and DSON Switching losses are ...
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Procedure: Place your application into a thermal chamber. You will need to dissipate enough power in the device so you can obtain a good thermal impedance value. Raise the ...
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Substituting I into The average inductor current the average output load. FIGURE 15. Inductor Volt-Sec Balance Waveform www.national.com Applying Charge balance on C1: Since there are no DC voltages across either inductor, and capacitor ...
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Steady State Analysis with Loss Elements Using inductor volt-second balance & capacitor charge bal- ance, the following equations are derived: Therefore: One can see that all variables are known except for the duty cycle (D). A quadratic equation is needed ...
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LM2735X SOT23-5 Design Example 1 Part ID U1 C1, Input Cap C2 Output Cap C3 Comp Cap D1, Catch Diode www.national.com LM2735X (1.6MHz): Vin = 5V, Vout = 12V @ 350mA Part Value Manufacturer 2.1A Boost ...
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LM2735Y SOT23-5 Design Example 2 LM2735Y (520kHz): Vin = 5V, Vout = 12V @ 350mA Part ID U1 2.1A Boost Regulator C1, Input Cap C2 Output Cap C3 Comp Cap D1, Catch Diode 0. Part Value ...
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LM2735X LLP-6 Design Example 3 Part Input Cap C2 Input Cap C3 Output Cap C4 Output Cap C5 Comp Cap D1, Catch Diode www.national.com LM2735X (1.6MHz): Vin = 3.3V, Vout = 12V @ ...
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LM2735Y LLP-6 Design Example 4 LM2735Y (520kHz): Vin = 3.3V, Vout = 12V @ 350mA Part ID U1 2.1A Boost Regulator C1 Input Cap C2 Input Cap C3 Output Cap C4 Output Cap C5 Comp Cap D1, Catch Diode 0.4V ...
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LM2735Y eMSOP-8 Design Example 5 Part Input Cap C2 Input Cap C3 Output Cap C4 Output Cap C5 Comp Cap D1, Catch Diode www.national.com LM2735Y (520kHz): Vin = 3.3V, Vout = 12V @ ...
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LM2735X SOT23-5 Design Example 6 LM2735X (1.6MHz): Vin = 3V, Vout = 5V @ 500mA Part ID U1 2.1A Boost Regulator C1, Input Cap C2, Output Cap C3 Comp Cap D1, Catch Diode 0. Part Value ...
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LM2735Y SOT23-5 Design Example 7 Part Input Cap C2 Output Cap C3 Comp Cap D1, Catch Diode www.national.com LM2735Y (520kHz): Vin = 3V, Vout = 5V @ 750mA Part Value Manufacturer 2.1A Boost ...
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LM2735X SOT23-5 Design Example 8 LM2735X (1.6MHz): Vin = 3.3V, Vout = 20V @ 100mA Part ID U1 2.1A Boost Regulator C1, Input Cap C2, Output Cap C3 Comp Cap D1, Catch Diode 0. Part ...
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LM2735Y SOT23-5 Design Example 9 Part Input Cap C2 Output Cap C3 Comp Cap D1, Catch Diode 0. www.national.com LM2735Y (520kHz): Vin = 3.3V, Vout = 20V @ 100mA Part Value Manufacturer 2.1A ...
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LM2735X LLP-6 Design Example 10 LM2735X (1.6MHz): Vin = 3.3V, Vout = 20V @ 150mA Part ID U1 2.1A Boost Regulator C1 Input Cap C2 Input Cap C3 Output Cap C4 Output Cap C5 Comp Cap D1, Catch Diode 0.4V ...
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LM2735Y LLP-6 Design Example 11 Part Input Cap C2 Input Cap C3 Output Cap C4 Output Cap C5 Comp Cap D1, Catch Diode 0. www.national.com LM2735Y (520kHz): Vin = 3.3V, Vout = 20V ...
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LM2735X LLP-6 SEPIC Design Example 12 LM2735X (1.6MHz): Vin = 2.7V - 5V, Vout = 3.3V @ 500mA Part ID U1 2.1A Boost Regulator C1 Input Cap C2 Input Cap C3 Output Cap C4 Output Cap C5 Comp Cap C6 ...
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LM2735Y eMSOP-8 SEPIC Design Example 13 LM2735Y (520kHz): Vin = 2.7V - 5V, Vout = 3.3V @ 500mA Part Input Cap C2 Input Cap C3 Output Cap C4 Output Cap C5 Comp Cap C6 D1, Catch Diode ...
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LM2735X SOT23-5 LED Design Example 14 LM2735X (1.6MHz): Vin = 2.7V - 5V, Vout = 20V @ 50mA Part ID U1 2.1A Boost Regulator C1 Input Cap C2 Output Cap D1, Catch Diode 0. Part ...
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LM2735Y LLP-6 FlyBack Design Example 15 Part Input Cap C2 Output Cap C3 Output Cap Cf Comp Cap D1, D2 Catch Diode 0. www.national.com LM2735Y (520kHz): Vin = 5V, Vout = ±12V 150mA ...
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Physical Dimensions inches (millimeters) unless otherwise noted 6-Lead LLP Package NS Package Number SDE06A 5-Lead SOT23-5 Package NS Package Number MF05A 35 www.national.com ...
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Package NS Package Number MUY08A 36 ...
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Notes 37 www.national.com ...
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