SFTB NSC [National Semiconductor], SFTB Datasheet
SFTB
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SFTB Summary of contents
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LM2734Z Thin SOT23 1A Load Step-Down DC-DC Regulator General Description The LM2734Z regulator is a monolithic, high frequency, PWM step-down DC/DC converter assembled in a 6-pin Thin SOT23 and LLP non pull back package. It provides all the active functions ...
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... DAP www.national.com 20130305 NSC Package Drawing Package Marking MK06A SFTB MK06A SFTB SDE06A L163B SDE06A L163B Name Boost voltage that drives the internal NMOS control switch. A bootstrap capacitor is connected between the BOOST and SW pins. GND Signal and Power ground pin. Place the bottom resistor of the feedback network as close as possible to this pin for accurate regulation ...
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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 ...
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Typical Performance Characteristics and 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 500mA OUT OUT www.national.com All curves ...
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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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Application Information current. Therefore recommended that V greater than 2.5V above V for best efficiency should not exceed the maximum operating limit of 5.5V. SW > > 5.5V V – V 2.5V for best performance. ...
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Application Information 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 ...
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Design Guide (Continued) The LM2734Z operates at frequencies allowing the use of ceramic output capacitors without compromising transient response. Ceramic capacitors allow higher inductor ripple without significantly increasing output ripple. See the output capacitor section for more details on calculating ...
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Design Guide (Continued) OUTPUT VOLTAGE The output voltage is set using the following equation where R2 is connected between the FB pin and GND, and R1 is connected between V and the FB pin. A good value for R2 O ...
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Calculating Efficiency, and Junction Temperature normally between 3VDC and 5VDC. The I BOOST rms current is approximately 4.25mA. Total power losses are: Design Example 1: Operating Conditions V 5. OUT V 2.5V P OUT DIODE I ...
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Calculating the LM2734Z Junction Temperature (Continued) The second method can give a very accurate silicon junction temperature. The first step is to determine R cation. The LM2734Z has over-temperature protection cir- cuitry. When the silicon temperature reaches 165˚C, the device ...
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LLP Package (Continued) For certain high power applications, the PCB land may be modified to a "dog bone" shape (see Figure 7). By increasing the size of ground plane, and adding thermal vias, the R for the application can be ...
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LM2734Z Design Examples Part ID Part Value U1 1A Buck Regulator C1, Input Cap 10µF, 6.3V, X5R C2, Output Cap 10µF, 6.3V, X5R C3, Boost Cap 0.01uF, 16V, X7R D1, Catch Diode 0.3V F D2, Boost Diode ...
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LM2734Z Design Examples 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 D1, Catch Diode 0.34V D2, Boost Diode 0.6V L1 3.3µH, 1.3A ...
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LM2734Z Design Examples 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 C4, Shunt Cap 0.1µF, 6.3V, X5R D1, Catch Diode 0.4V F ...
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LM2734Z Design Examples FIGURE 11. V 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 D1, Catch Diode 0.4V D2, Boost Diode 1V ...
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LM2734Z Design Examples FIGURE 12. V Part ID Part Value U1 1A Buck Regulator C1, Input Cap 10µF, 25V, X7R C2, Output Cap 22µF, 16V, X5R C3, Boost Cap 0.01µF, 16V, X7R D1, Catch Diode 0.4V F D2, Boost Diode ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 6-Lead SOT23 Package NS Package Number MK06A 6-Lead LLP Package NS Package Number SDE06A 18 ...
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National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. For the most current product information ...