LM2734XMK National Semiconductor, LM2734XMK Datasheet
LM2734XMK
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LM2734XMK Summary of contents
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... Additional features include internal soft-start circuitry to reduce inrush current, pulse-by-pulse current limit, thermal shutdown, and output over-voltage protection. Typical Application Circuit WEBENCH™ trademark of Transim. © 2007 National Semiconductor Corporation Features ■ Thin SOT23-6 package ■ 3.0V to 20V input voltage range ■ ...
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... Connection Diagrams 6-Lead TSOT NS Package Number MK06A Ordering Information Order Number Package Type LM2734XMK LM2734YMK TSOT-6 LM2734XMKX LM2734YMKX * Contact the local sales office for the lead-free package. Pin Descriptions Pin www.national.com 20102305 NSC Package Drawing Package Marking SFDB ...
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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 Boost Voltage Boost to SW Voltage FB Voltage EN Voltage Junction Temperature ESD Susceptibility (Note 2) Electrical Characteristics Specifications with standard typeface are for T Range (T = -40° ...
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Typical Performance Characteristics µH ("Y"), and T = 25°C, unless specified otherwise. A Efficiency vs Load Current - "X" V Efficiency vs Load Current - "X" V Efficiency vs Load Current - "X" V www.national.com All curves ...
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Oscillator Frequency vs Temperature - "X" Current Limit vs Temperature Temperature FB Oscillator Frequency vs Temperature - "Y" 20102327 Current Limit vs Temperature 20102329 R DSON 20102333 5 20102328 V = 20V IN 20102347 ...
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I Switching vs Temperature Q Line Regulation - "Y" 1.5V, I OUT OUT Line Regulation - "Y" 3.3V, I OUT OUT www.national.com 20102346 = 500mA 20102354 = 500mA 20102353 6 Line Regulation - "X" ...
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Block Diagram Application Information THEORY OF OPERATION The LM2734 is a constant frequency PWM buck regulator IC that delivers a 1A load current. The regulator has a preset switching frequency of either 550kHz (LM2734Y) or 1.6MHz (LM2734X). These high frequencies ...
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V – V should not exceed the max- BOOST SW imum operating limit of 5.5V. 5.5V > V – V > 2.5V for best performance. BOOST SW FIGURE 3. V Charges C OUT When the LM2734 starts ...
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FIGURE 5. Boost Voltage Supplied from the Shunt Zener ENABLE PIN / SHUTDOWN MODE The LM2734 has a shutdown mode that is controlled by the enable pin (EN). When a logic low voltage is applied to EN, ...
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Now that the ripple current or ripple ratio is determined, the inductance is calculated by: where f is the switching frequency and I s rent. When selecting an inductor, ...
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PCB Layout Considerations When planning layout there are a few things to consider when trying to achieve a clean, regulated output. The most impor- tant consideration when completing the layout is the close coupling of the GND connections of the ...
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... FIGURE 6. LM2734X (1.6MHz) V Derived from V BOOST 5V to 1.5V/1A Bill of Materials for Figure 6 Part Number LM2734X C3216X5ROJ106M C3216X5ROJ106M C1005X7R1C103K Schottky 1A, 10VR MBRM110L F @ 50mA Diode 1N4148W F VLCF4020T- 4R7N1R2 CRCW06038871F CRCW06031022F CRCW06031003F 12 20102342 IN Manufacturer National Semiconductor TDK TDK TDK ON Semi Diodes, Inc. TDK Vishay Vishay Vishay ...
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Part ID Part Value U1 1A Buck Regulator C1, Input Cap 10µF, 25V, X7R C2, Output Cap 22µF, 6.3V, X5R C3, Boost Cap 0.01µF, 16V, X7R CFF 1000pF 25V D1, Catch Diode 0.34V F D2, Boost Diode 1V @ 50mA ...
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... Bill of Materials for Figure 8 Part Number LM2734X C3225X7R1E106M C3216X5ROJ226M C1005X7R1C103K C1005X5R0J104K Schottky 1A, 30VR SS1P3L F @ 50mA Diode 1N4148W F BZX84C5V1 SLF7032T-6R8M1R6 CRCW06038871F CRCW06031022F CRCW06031003F CRCW06034121F 14 20102344 Manufacturer National Semiconductor TDK TDK TDK TDK Vishay Diodes, Inc. Vishay TDK Vishay Vishay Vishay Vishay ...
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... Derived from Series Zener Diode (V BOOST 15V to 1.5V/1A Bill of Materials for Figure 9 Part Number LM2734X C3225X7R1E106M C3216X5ROJ226M C1005X7R1C103K SS1P3L 1N4148W BZX84C11T SLF7032T-6R8M1R6 CRCW06038871F CRCW06031022F CRCW06031003F 15 20102349 ) IN Manufacturer National Semiconductor TDK TDK TDK Vishay Diodes, Inc. Diodes, Inc. TDK Vishay Vishay Vishay www.national.com ...
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... Derived from Series Zener Diode (V BOOST 15V to 9V/1A Bill of Materials for Figure 10 Part Number LM2734X C3225X7R1E106M C3216X5R1C226M C1005X7R1C103K Schottky 1A, 30VR SS1P3L F @ 50mA Diode 1N4148W F BZX84C4V3 SLF7032T-6R8M1R6 CRCW06031023F CRCW06031022F CRCW06031003F 16 20102350 ) OUT Manufacturer National Semiconductor TDK TDK TDK Vishay Diodes, Inc. Diodes, Inc. TDK Vishay Vishay Vishay ...
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... R3 FIGURE 11. LM2734Y (550kHz) V Derived from V BOOST 1.5V/1A Bill of Materials for Figure 11 Part Number LM2734Y C3216X5ROJ106M C3216X5ROJ226M C1005X7R1C103K MBRM110L 1N4148W SLF7032T-100M1R4 CRCW06038871F CRCW06031022F CRCW06031003F 17 20102342 Manufacturer National Semiconductor TDK TDK TDK ON Semi Diodes, Inc. TDK Vishay Vishay Vishay www.national.com ...
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... FIGURE 12. LM2734Y (550kHz) V Derived from V BOOST OUT 12V to 3.3V/1A Bill of Materials for Figure 12 Part Number LM2734Y C3225X7R1E106M C3216X5ROJ226M C1005X7R1C103K Schottky 1A, 30VR SS1P3L F @ 30mA Diode BAT17 F SLF7032T-100M1R4 CRCW06033162F CRCW06031002F CRCW06031003F 18 20102343 Manufacturer National Semiconductor TDK TDK TDK Vishay Vishay TDK Vishay Vishay Vishay ...
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... Derived from V BOOST SHUNT 18V to 1.5V/1A Bill of Materials for Figure 13 Part Number LM2734Y C3225X7R1E106M C3216X5ROJ226M C1005X7R1C103K C1005X5R0J104K SS1P3L 1N4148W BZX84C5V1 SLF7045T-150M1R5 CRCW06038871F CRCW06031022F CRCW06031003F CRCW06034121F 19 20102344 Manufacturer National Semiconductor TDK TDK TDK TDK Vishay Diodes, Inc. Vishay TDK Vishay Vishay Vishay Vishay www.national.com ...
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... Derived from Series Zener Diode (V BOOST 15V to 1.5V/1A Bill of Materials for Figure 14 Part Number LM2734Y C3225X7R1E106M C3216X5ROJ226M C1005X7R1C103K Schottky 1A, 30VR SS1P3L F @ 50mA Diode 1N4148W F BZX84C11T SLF7045T-150M1R5 CRCW06038871F CRCW06031022F CRCW06031003F 20 20102349 ) IN Manufacturer National Semiconductor TDK TDK TDK Vishay Diodes, Inc. Diodes, Inc. TDK Vishay Vishay Vishay ...
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... Derived from Series Zener Diode (V BOOST 15V to 9V/1A Bill of Materials for Figure 15 Part Number LM2734Y C3225X7R1E106M C3216X5R1C226M C1005X7R1C103K SS1P3L 1N4148W BZX84C4V3 SLF7045T-220M1R3-1PF CRCW06031023F CRCW06031022F CRCW06031003F 21 20102350 ) OUT Manufacturer National Semiconductor TDK TDK TDK Vishay Diodes, Inc. Diodes, Inc. TDK Vishay Vishay Vishay www.national.com ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 6-Lead TSOT Package NS Package Number MK06A 22 ...
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Notes 23 www.national.com ...
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