LM20333EVAL National Semiconductor, LM20333EVAL Datasheet
LM20333EVAL
Specifications of LM20333EVAL
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LM20333EVAL Summary of contents
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... The LM20333 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 ® PowerWise is a registered trademark of National Semiconductor Corporation. © 2009 National Semiconductor Corporation Features ■ 4.5V to 36V input voltage range ■ ...
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Connection Diagram Ordering Information Order Number Package Type LM20333MH eTSSOP-20 LM20333MHE LM20333MHX 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, COMP, SYNC, 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 g Error Amplifier DC Transconductance m A Error Amplifier Voltage Gain VOL GBW Error Amplifier Gain-Bandwidth Product Current Limit I Cycle By Cycle Positive Current Limit LIM I Cycle By Cycle Negative Current Limit LIMNEG T Cycle By ...
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Efficiency vs. Load Current f = 750 kHz SW 30051685 Error Amplifier Phase 30051606 Load Regulation 30051686 Error Amplifier Gain Line Regulation V vs 30051605 30051607 30051608 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 30051609 Enable Threshold and Hysteresis vs. Temperature PGOOD 30051619 30051695 6 Shutdown I vs 30051610 30051621 Enable ...
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Clock Synchronization Low-Side FET Resistance vs. Temperature Peak Current Limit vs. Temperature High-Side FET Resistance vs. Temperature 30051680 Load Transient Response 30051657 Startup with prebiased output 30051658 7 30051655 30051656 30051679 www.national.com ...
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Startup with C Startup with applied Track Signal www.national.com = 0 SS 30051659 30051681 8 Startup with C = 100 nF SS 30051660 ...
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Block Diagram 9 30051623 www.national.com ...
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Operation Description GENERAL The LM20333 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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PGOOD pin has 20 µs of built in deglitch time to both rising and falling edges. UVLO The LM20333 has an internal under-voltage lockout protec- tion circuit that keeps the device from switching until the input voltage reaches ...
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If the ripple current in the inductor is too low, the control loop will not have suffi- cient current sense information and can be prone to instability. OUTPUT CAPACITOR SELECTION (C The output ...
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TABLE 2. Recommended Compensation for C = 150 µ 3A, f OUT OUT (µ OUT 6.8 30.9 12 3.3 5.6 33.2 12 2.5 4.7 40.2 12 1.5 3.3 22.1 ...
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SETTING THE START UP TIME (C The addition of a capacitor connected from the SS pin to ground sets the time at which the output voltage will reach the final regulated value. Larger values for C start up times. Table ...
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FIGURE 7. Common Start Up Sequences A simultaneous start up is preferred when powering most FP- GAs, DSPs, or other microprocessors. In these systems the higher voltage usually powers the I/O, and the lower OUT1 voltage ...
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FIGURE 8. Safe Thermal Operating Areas (I = 350kHz) FIGURE 9. Safe Thermal Operating Areas (I = 500kHz) FIGURE 10. Safe Thermal Operating Areas ( 750kHz) SW www.national.com 30051690 = 3A, f FIGURE 11. Safe Thermal Operating Areas ...
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These can send erroneous signals to the DC-DC converter resulting in poor regulation or instability. Good layout can be implemented by following a few simple design rules. 1. Minimize area of ...
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Bill of Materials (V = 12V Qty Part Number U1 1 LM20333MH C1 1 C3225X5R1E226M C2 GRM21BR61E475KA12L C5 C1608X7R1H104K C4 1 C1608X5R1A105K C7 1 C1608C0G1H100J C8 1 C1608C0G1H152J 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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