LM5022LEDEVAL National Semiconductor, LM5022LEDEVAL Datasheet
LM5022LEDEVAL
Specifications of LM5022LEDEVAL
Related parts for LM5022LEDEVAL
LM5022LEDEVAL Summary of contents
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... Additional features include an error amplifier, precision reference, line under-voltage lockout, cycle-by-cy- cle current limit, slope compensation, soft-start, external syn- chronization capability and thermal shutdown. The LM5022 is available in the MSOP-10 package. Typical Application © 2009 National Semiconductor Corporation LM5022 Features ■ Internal 60V Startup Regulator ■ ...
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Connection Diagram Ordering Information Part Number LM5022MM LM5022MMX LM5022MME Pin Descriptions Pin(s) Name Description 1 VIN Source input voltage 2 FB Feedback pin Error amplifier output and PWM 3 COMP comparator input Output of the internal, high voltage linear 4 ...
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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 VCC to GND RT/SYNC to GND OUT to GND All other pins to GND Power Dissipation Junction Temperature Electrical Characteristics junction temperature (T ) range of -40°C to +125°C. Minimum and Maximum limits are guaranteed through test, design, or statistical J correlation ...
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Symbol Parameter SOFT-START I Soft-start Current Source SS V Soft-start to COMP Offset SS-OFF OSCILLATOR RT to GND = 84.5 kΩ GND = 27.4 kΩ GND = 16.2 kΩ V Synchronization Rising Threshold SYNC-HI ...
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Typical Performance Characteristics Efficiency 40V O Example Circuit BOM V vs 25° Max Duty Cycle vs 20212255 20212204 = 25° 20212206 5 V vs. Temp (V ...
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R vs OUT Pin t vs. Gate Capacitance RISE www.national.com = 25°C) 20212208 20212210 6 SS vs. Temperature 20212209 OUT Pin t vs. Gate Capacitance FALL 20212211 ...
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Block Diagram 7 20212212 www.national.com ...
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Example Circuit Applications Information OVERVIEW The LM5022 is a low-side N-channel MOSFET controller that contains all of the features needed to implement single ended power converter topologies. The LM5022 includes a high- voltage startup regulator that operates over a wide ...
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FIGURE 2. Enable/Disable Using UVLO ERROR AMPLIFIER An internal high gain error amplifier is provided within the LM5022. The amplifier’s non-inverting input is internally set to a fixed reference voltage of 1.25V. The inverting input is con- nected to the ...
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The slope of the compensation ramp SW increases when external resistance is added for filtering the current sense ( the position ...
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The factor 1.3 accounts for the increase in MOSFET on re- sistance due to heating. Alternatively, the factor of 1.3 can be ignored and the maximum on resistance of the MOSFET can be used. Gate charging loss results ...
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Inductance for Maximum Input Voltage 0.5) / (40 + 0.5) = 60% VIN(MAX 0 – 0.6) = 1.25A L-VIN(MIAX) Δi = 0.4 x 1.25A = 0.5A L Maximum average inductor ...
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FIGURE 6. ΔV Using Low ESR Capacitors O For this example the small size and high temperature rating of ceramic capacitors make them a good choice. The output ripple voltage waveform of Figure 6 is assumed, and the ca- pacitance ...
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The next highest standard 20% capacitor value is 6.8 µF, but because the actual input source impedance and resistance are not known, two 4.7 µF capacitors will be used. In general, doubling the calculated value of input capacitance provides a ...
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FIGURE 7. Power Stage and Error Amp One popular method for selecting the compensation compo- nents is to create Bode plots of gain and phase for the power stage and error amplifier. Combined, they make the overall bandwidth and phase ...
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FIGURE 8. Power Stage Gain and Phase The single pole causes a roll-off in the gain of -20 dB/decade at lower frequency. The combination of the RHP zero and sampling double pole maintain the slope out to beyond the switching ...
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FIGURE 9. Error Amplifier Gain and Phase 12. Plot or evaluate the complete control loop transfer function: The complete control loop transfer function is ob- tained by multiplying the power stage and error amplifier functions together. The bandwidth and phase ...
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P = 13.8 X (3.5m + 13.5m) = 235 mW Q MOSFET SWITCHING LOSS 0.5 x 13.8 x 1 ns) x ...
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The dark grey, inner loops represents the high current paths during the MOSFET on-time. The light grey, outer loop rep- resents the high current path during the off-time. GROUND PLANE AND SHAPE ROUTING The diagram of Figure 11 is also ...
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BOM for Example Circuit ID Part Number U1 LM5022 Q1 Si4850EY D1 CMSH2-60M L1 SLF12575T-M3R2 Cin1, Cin2 C4532X7R1H475M Co1, Co2 C5750X7R2A475M Cf C2012X7R1E105K Cinx C2012X7R2A104M Cox C1 VJ0805A561KXXAT C2 VJ0805Y124KXXAT Css VJ0805Y103KXXAT Ccs VJ0805Y102KXXAT R1 CRCW08053011F Rfb1 CRCW08056490F Rfb2 CRCW08052002F ...
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Physical Dimensions inches (millimeters) unless otherwise noted 10-Lead MSOP Package NS Package Number MUB10A 21 www.national.com ...
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