LM20343MH/NOPB National Semiconductor, LM20343MH/NOPB Datasheet
LM20343MH/NOPB
Specifications of LM20343MH/NOPB
*LM20343MH/NOPB
LM20343MH
Related parts for LM20343MH/NOPB
LM20343MH/NOPB Summary of contents
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... The LM20343 is offered in an exposed pad 20-pin eTSSOP package that can be soldered to the PCB, eliminating the need for bulky heatsinks. Simplified Application Circuit © 2008 National Semiconductor Corporation Features ■ 4.5V to 36V input voltage range ■ ...
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Connection Diagram Ordering Information Order Number Package Type LM20343MH eTSSOP-20 LM20343MHE LM20343MHX Pin Descriptions Pin(s) Name Description 1 SS/TRK Soft-Start or Tracking control input 2 FB Feedback input to the error amplifier from the regulated output 3 PGOOD Power good ...
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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. VIN to GND BOOT to GND BOOT GND SW to GND (Transient) FB, EN, SS/TRK, RT, PGOOD to GND Electrical Characteristics type are for T = 25°C only, limits in bold face type apply over the junction temperature (T J and Maximum limits are guaranteed through test, design, or statistical correlation ...
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Symbol Parameter Current Limit I Cycle By Cycle Positive Current Limit LIM I Cycle By Cycle Negative Current Limit LIMNEG T Cycle By Cycle Current Limit Delay ILIM Enable V EN Pin Rising Threshold EN(RISING Pin Hysteresis EN(HYS) ...
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Efficiency vs. Load Current f = 750 kHz SW 30051785 Error Amplifier Phase 30051706 Load Regulation 30051786 Error Amplifier Gain Line Regulation V vs 30051705 30051707 30051708 www.national.com ...
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Non-Switching I PGOOD Output Low Level Voltage vs. I UVLO Threshold and Hysteresis vs. Temperature www.national.com vs 30051709 EN Threshold and Hysteresis vs. Temperature PGOOD 30051719 30051795 6 Shutdown I vs 30051710 30051721 EN ...
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Oscillator Frequency vs 30051753 Load Transient Response 30051756 Peak Current Limit vs. Temperature 30051758 High-Side FET Resistance vs. Temperature Low-Side FET Resistance vs. Temperature Startup with output voltage prebias 7 30051755 30051757 30051779 www.national.com ...
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Startup with C Startup with applied Track Signal www.national.com = 0 SS 30051759 30051781 8 Startup with C = 100 nF SS 30051760 ...
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Block Diagram 9 30051723 www.national.com ...
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Operation Description GENERAL The LM20343 switching regulator features all of the functions necessary to implement an efficient buck regulator using a minimum number of external components. This easy to use regulator features two integrated switches and is capable of supplying ...
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Design Guide This section walks the designer through the steps necessary to select the external components to build a fully functional power supply. As with any DC-DC converter numerous trade- offs are ...
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C (F) is the minimum required output capacitance, OUT L (H) is the value of the inductor, V voltage drop ignoring loop bandwidth considerations, ΔI (A) is the load step change, R STEP capacitor ESR, V (V) is the ...
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FIGURE 3. LM20343 Loop Compensation The power stage transfer function is dictated by the modula- tor, output LC filter, and load; while the feedback transfer function is set by the feedback resistor ratio, error amp gain and external compensation network. ...
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When the device is enabled there is an approximate time interval of 50 µs when the soft-start capac- itor will be discharged ...
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Similar to the soft-start function, the fastest start up possible is 1ms regardless of the rise time of the tracking voltage. When using the track feature the final voltage seen by the SS/ TRACK pin should exceed 1V to provide ...
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FIGURE 10. Safe Thermal Operating Areas ( 750 kHz) SW FIGURE 11. Safe Thermal Operating Areas ( 500 kHz) SW The dashed lines in the figures above show an approximation of the minimum and maximum duty ...
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Voltage accuracy at the load is important so make sure feedback voltage sense is made at the load. Doing so will correct for voltage drops at the load and provide the best output accuracy. ...
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Bill of Materials (V = 12V Qty Part Number U1 1 LM20343MH C1 1 C3225X5R1E226M C2 GRM21BR61E475KA12L C5 C1608X7R1H104K C4 1 C1608X5R1A105K C7 1 C1608C0G1H100J C8 1 C1608C0G1H102J C9 1 6TPB150MAZB D1 1 ...
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Physical Dimensions inches (millimeters) unless otherwise noted 20-Lead eTSSOP Package NS Package Number MXA20A 19 www.national.com ...
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