LM25011MY/NOPB National Semiconductor, LM25011MY/NOPB Datasheet
LM25011MY/NOPB
Specifications of LM25011MY/NOPB
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LM25011MY/NOPB Summary of contents
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... The LM25011A has a shorter minimum off-time than the LM25011, which allows for higher frequency operation at low input voltages. Typical Application, Basic Step-Down Regulator © 2011 National Semiconductor Corporation LM25011/LM25011Q LM25011A/LM25011AQ Features ■ LM25011Q is an Automotive Grade product that is AEC- Q100 grade 1 qualified (-40° ...
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Connection Diagram Ordering Information Order Number Package Type LM25011MY MSOP-10EP LM25011MYX MSOP-10EP LM25011AMY MSOP-10EP LM25011AMYX MSOP-10EP LM25011Q1MY MSOP-10EP LM25011Q1MYX MSOP-10EP LM25011AQ1MY MSOP-10EP LM25011AQ1MYX MSOP-10EP *Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive market, including defect ...
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Pin Descriptions Pin No. Name Description 1 VIN Input supply voltage 2 RT On-time Control 3 PGD Power Good 4 SS Soft-Start 5 SGND Signal Ground 6 FB Feedback 7 CSG Current Sense Ground 8 CS Current sense 9 SW ...
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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 SGND (T = 25°C) J BST to SGND SW to SGND (Steady State) BST CSG CSG to SGND PGD to SGND SS to SGND Electrical Charateristics over the full Operating Junction Temperature (T statistical correlation ...
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Symbol Parameter Regulation Comparator (FB Pin regulation threshold REF FB bias current Power Good (PGD pin) Threshold at FB, with respect to V Threshold hysteresis PGD Low state voltage VOL PGD Off state leakage LKG Thermal Shutdown T ...
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Typical Performance Characteristics Efficiency (Circuit of Figure 5) On-Time Shutdown Current into VIN www.national.com 30094603 and R T 30094605 30094607 6 Efficiency at 2 MHz 30094604 Voltage at the RT Pin 30094606 Operating Current into VIN 30094608 ...
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PGD Low Voltage vs. Sink Current Current Limit Threshold vs. Temperature 30094611 VIN UVLO vs. Temperature 30094613 Reference Voltage vs. Temperature 30094609 Operating Current vs. Temperature SS Pin ShutdownThreshold vs. Temperature 7 30094610 30094612 30094614 www.national.com ...
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On-Time vs. Temperature www.national.com Minimum Off-Time vs. Temperature 190 170 150 130 110 -40 -20 JUNCTION TEMPERATURE (°C) 30094615 8 LM25011 LM25011A 100 120 30094651 ...
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Block Diagram 9 www.national.com ...
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Functional Description The LM25011 Constant On-time Step-down Switching Reg- ulator features all the functions needed to implement a low cost, efficient buck bias power converter capable of supplying up to 2.0A to the load. This high voltage regulator contains an ...
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The approximate operating frequency is calculated as follows: The buck switch duty cycle is approximately equal to: When the load current is less than one half the inductor’s rip- ple current amplitude the circuit operates in discontinuous conduction mode. ...
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Ripple Requirements The LM25011 requires about 25mVp-p of ripple voltage at the CS pin. Higher switching frequency may require more ripple. That ripple voltage is generated by the decreasing recirculat- ing current (the inductor’s ripple current) through R the off-time. ...
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SS pin must be current limited to a maximum of 1 mA. Shutdown Function The SS pin can be used to shutdown the LM25011 by ground- ing the SS pin as shown in Figure 4. Releasing the ...
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The minimum ripple current, which occurs at minimum The minimum current limit threshold is calculated at max- S imum load current, using the minimum ripple current calcu- lated ...
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FIGURE 6. Efficiency (Circuit of Figure FIGURE 7. Frequency vs V (Circuit of IN FIGURE 5. Example Circuit OUTPUT RIPPLE CONTROL (LM25011A) The LM25011A most likely will require more ripple voltage than is generated across the RS resistor. Additional ripple ...
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FIGURE 8. Option A – Lowest Cost Ripple Configuration Option B) Intermediate Ripple Configuration: This config- uration generates less ripple at V OUT the addition of one capacitor (Cff), as shown in Figure 9. FIGURE 9. Option B – Intermediate ...
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PC board’s ground plane can help to dissipate heat. Ad- ditionally the use of wide PC board traces, where possible, can help conduct heat away from the IC pins. Judicious po- sitioning of the PC board within the end ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 10-Lead MSSOP-EP Package NS Package Number MUC10A 18 ...
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Notes 19 www.national.com ...
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