LM2734ZEVAL National Semiconductor, LM2734ZEVAL Datasheet
LM2734ZEVAL
Specifications of LM2734ZEVAL
Related parts for LM2734ZEVAL
LM2734ZEVAL Summary of contents
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... Additional features include internal soft-start circuitry to re- duce inrush current, pulse-by-pulse current limit, thermal shutdown, and output over-voltage protection. Typical Application Circuit WEBENCH™ trademark of Transim. © 2008 National Semiconductor Corporation Features ■ Thin SOT23-6 package lead LLP 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 LM2734ZMK LM2734ZMKX LM2734ZQMKE TSOT-6 LM2734ZQMK LM2734ZQMKX LM2734ZSD LM2734ZSDX LM2734ZQSDE 6-Lead LLP LM2734ZQSD LM2734ZQSDX *Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive ...
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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) Storage Temp. Range Electrical Characteristics Specifications with standard typeface are for T Range (T = -40° ...
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Typical Performance Characteristics T = 25°C, unless specified otherwise. A Efficiency vs Load Current OUT Efficiency vs Load Current V = 1.5V OUT Line Regulation V = 1.5V, I OUT OUT www.national.com All curves taken at V ...
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Block Diagram Application Information THEORY OF OPERATION The LM2734Z is a constant frequency PWM buck regulator IC that delivers a 1A load current. The regulator has a preset switching frequency of 3MHz. This high frequency allows the LM2734Z to operate ...
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BOOST FUNCTION Capacitor C and diode D2 in Figure 3 are used to gen- BOOST erate a voltage BOOST BOOST SW to the internal NMOS control switch. To properly drive the in- ternal NMOS switch ...
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FIGURE 5. Boost Voltage Supplied from the Shunt Zener ENABLE PIN / SHUTDOWN MODE The LM2734Z 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, make sure that it is capable of supporting the peak output ...
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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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Calculating the LM2734Z Junction Temperature Thermal Definitions Chip junction temperature Ambient temperature A FIGURE 6. Cross-Sectional View of Integrated Circuit Mounted on a Printed Circuit Board. Heat in the LM2734Z due to ...
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... D 75mW 53mW 53mW 187mW 7.5mW Using a standard National Semiconductor Thin SOT23-6 demonstration board to determine the R 21mW four layer PCB is constructed using FR4 with 1/2oz copper 548mW traces. The copper ground plane is on the bottom layer. The ground plane is accessed by two vias. The board measures 2.5cm x 3cm. It was placed in an oven with no forced airflow. The ambient temperature was raised to 94° ...
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... D 30.3% This example follows example 2, but uses the LLP package. Using a standard National Semiconductor LLP-6 demonstra- tion board, use Method 2 to determine R four layer PCB is constructed using FR4 with 1/2oz copper traces. The copper ground plane is on the bottom layer. The ground plane is accessed by four vias ...
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Package Selection To determine which package you should use for your specific application, variables need to be known before you can de- termine the appropriate package to use. 1. Maximum ambient system temperature 2. Internal LM2734Z power losses 3. Maximum ...
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... Derived from V BOOST Operating Conditions 1.5V/1A Bill of Materials for Figure 8 Part Number LM2734ZX C3216X5ROJ106M C3216X5ROJ106M C1005X7R1C103K Schottky 1A, 10VR MBRM110L F @ 50mA Diode 1N4148W F ME3220–222MX CRCW06038871F CRCW06031022F CRCW06031003F 14 20130342 IN Manufacturer National Semiconductor TDK TDK TDK ON Semi Diodes, Inc. Coilcraft Vishay Vishay Vishay ...
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... FIGURE 9. V Derived from V BOOST 12V to 3.3V/1A Bill of Materials for Figure 9 Part Number LM2734ZX C3225X7R1E106M C3216X5ROJ226M C1005X7R1C103K Schottky 1A, 30VR SS1P3L BAT17 ME3220–332MX CRCW06033162F CRCW06031002F CRCW06031003F 15 20130343 OUT Manufacturer National Semiconductor TDK TDK TDK Vishay Vishay Coilcraft Vishay Vishay Vishay www.national.com ...
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... Bill of Materials for Figure 10 Part Number LM2734ZX C3225X7R1E106M C3216X5ROJ226M C1005X7R1C103K C1005X5R0J104K Schottky 1A, 30VR SS1P3L F @ 50mA Diode 1N4148W F BZX84C5V1 ME3220–332MX CRCW06038871F CRCW06031022F CRCW06031003F CRCW06034121F 16 20130344 SHUNT Manufacturer National Semiconductor TDK TDK TDK TDK Vishay Diodes, Inc. Vishay Coilcraft 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 11 Part Number LM2734ZX C3225X7R1E106M C3216X5ROJ226M C1005X7R1C103K SS1P3L 1N4148W BZX84C11T ME3220–332MX CRCW06038871F CRCW06031022F CRCW06031003F 17 20130349 ) IN Manufacturer National Semiconductor TDK TDK TDK Vishay Diodes, Inc. Diodes, Inc. Coilcraft Vishay Vishay Vishay www.national.com ...
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... Bill of Materials for Figure 12 Part Number LM2734ZX C3225X7R1E106M C3216X5R1C226M C1005X7R1C103K Schottky 1A, 30VR SS1P3L F @ 50mA Diode 1N4148W F BZX84C4V3 ME3220–222MX CRCW06031023F CRCW06031022F CRCW06031003F 18 20130350 ) OUT Manufacturer National Semiconductor TDK TDK TDK Vishay Diodes, Inc. Diodes, Inc. Coilcraft Vishay Vishay Vishay ...
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Physical Dimensions inches (millimeters) unless otherwise noted 6-Lead SOT23 Package NS Package Number MK06A 6-Lead LLP Package NS Package Number SDE06A 19 www.national.com ...
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