LM2575 - 1.0 A, Adjustable Output Voltage, Step-Down ...

1 DATA Semiconductor Components Industries, LLC, 2009 December, 2022 Rev. 121 Publication Order Number: LM2575 /DRegulator, Step-DownSwitching, AdjustableOutput voltage , ALM2575, NCV2575 The LM2575 series of regulators are monolithic integrated circuitsideally suited for easy and convenient design of a step downswitching regulator (buck converter). All circuits of this series arecapable of driving a A load with excellent line and load devices are available in fixed Output voltages of V, V,12 V, 15 V, and an Adjustable Output regulators were designed to minimize the number of externalcomponents to simplify the power supply design. Standard series ofinductors optimized for use with the LM2575 are offered by severaldifferent inductor the LM2575 converter is a switch mode power supply, itsefficiency is significantly higher in comparison with popularthree terminal linear regulators , especially with higher input many cases, the power dissipated by the LM2575 regulator is solow, that no heatsink is required or its size could be LM2575 features include a guaranteed 4% tolerance on outputvoltage within specified input voltages and Output load conditions, and 10% on the oscillator frequency ( 2% over 0 C to 125 C).

2 Externalshutdown is included, featuring 80 mA typical standby current. Theoutput switch includes cycle by cycle current limiting, as well asthermal shutdown for full protection under fault V, V, 12 V, 15 V, and Adjustable Output Versions Adjustable Version Output voltage Range of V to 37 V 4%Maximum Over Line and Load Conditions Guaranteed A Output Current Wide Input voltage Range: V to 40 V Requires Only 4 External Components 52 kHz Fixed Frequency Internal Oscillator TTL Shutdown Capability, Low Power Standby Mode High Efficiency Uses Readily Available Standard Inductors Thermal Shutdown and Current Limit Protection Moisture Sensitivity Level (MSL) Equals 1 NCV Prefix for Automotive and Other Applications RequiringUnique Site and Control Change Requirements.

3 AEC Q100 Qualified and PPAP Capable These are Pb Free DevicesSee detailed ordering and shipping information in the packagedimensions section on page 24 of this data INFORMATION15TO 220TV SUFFIXCASE 314B1515 Heatsink surface connected to Pin 3TO 220T SUFFIXCASE 314 DPin 1. Vin2. Output3. Ground4. Feedback5. ON/OFFD2 PAKD2T SUFFIXCASE 936 AHeatsink surface (shown as terminal 6 incase outline drawing) is connected to Pin 3 See general marking information in the device markingsection on page 25 of this data MARKING INFORMATIONA pplications Simple and High Efficiency Step Down(Buck) regulators Efficient Pre Regulator for Linear regulators On Card Switching regulators Positive to Negative Converters (Buck Boost) Negative Step Up Converters Power Supply for Battery ChargersLM2575, 1.

4 Block Diagram and Typical V - 40 VUnregulated DC InputL1330 mHGND+Vin1 Cin100 mF3ON/OFF5 Output2 Feedback4D11N5819 Cout330 mFTypical Application (Fixed Output voltage Versions)Representative Block Diagram and Typical ApplicationUnregulatedDC Input+ kOutput2 GND3ON/OFF5 ResetLatchThermalShutdown52 VBand-GapReferenceFreqShift18 kHzComparatorFixed GainError V InternalRegulatorRegulatedOutputVoutLoad OutputVoltage V12 V15 VR2(W) kFor Adjustable versionR1 = open, R2 = 0 V Regulated Output A LoadThis device contains 162 active MAXIMUM RATINGS (Absolute Maximum Ratings indicate limits beyond which damage to the device may occur.)RatingSymbolValueUnitMaximum Supply VoltageVin45 VON/OFF Pin Input voltage V V +VinVOutput voltage to Ground (Steady State) DissipationCase 314B and 314D (TO 220, 5 Lead)PDInternally LimitedWThermal Resistance, Junction to AmbientRqJA65 C/WThermal Resistance, Junction to C/WCase 936A (D2 PAK)PDInternally LimitedWThermal Resistance, Junction to Ambient (Figure 34)RqJA70 C/WThermal Resistance, Junction to C/WStorage Temperature RangeTstg 65 to +150 CMinimum ESD Rating (Human Body Model: C = 100 pF, R = kW) Temperature (Soldering, 10 s) 260 CMaximum Junction TemperatureTJ150 CStresses exceeding those listed in the Maximum Ratings table may damage the device.

5 If any of these limits are exceeded, device functionalityshould not be assumed, damage may occur and reliability may be , RATINGS (Operating Ratings indicate conditions for which the device is intended to be functional, but do not guaranteespecific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics.)RatingSymbolValueUnitOp erating Junction Temperature RangeTJ 40 to +125 CSupply VoltageVin40 VSYSTEM PARAMETERS ([Note 1] Test Circuit Figure 14)ELECTRICAL CHARACTERISTICS (Unless otherwise specified, Vin = 12 V for the V, V, and Adjustable version, Vin = 25 Vfor the 12 V version, and Vin = 30 V for the 15 V version. ILoad = 200 mA. For typical values TJ = 25 C, for min/max values TJ is theoperating junction temperature range that applies [Note 2], unless otherwise noted.)

6 CharacteristicsSymbolMinTypMaxUnitLM2575 (Note 1 Test Circuit Figure 14) Output voltage (Vin = 12 V, ILoad = A, TJ = 25 C) voltage ( V Vin 40 V, A ILoad A)VoutVTJ = 25 = 40 to +125 (Vin = 12 V, ILoad = A) 75 % LM2575 5 ([Note 1] Test Circuit Figure 14) Output voltage (Vin = 12 V, ILoad = A, TJ = 25 C) voltage ( V Vin 40 V, A ILoad A)VoutVTJ = 25 = 40 to +125 (Vin = 12 V, ILoad = A) 77 % LM2575 12 (Note 1 Test Circuit Figure 14) Output voltage (Vin = 25 V, ILoad = A, TJ = 25 C) voltage (15 V Vin 40 V, A ILoad A)VoutVTJ = 25 = 40 to +125 (Vin = 15V, ILoad = A) 88 % LM2575 15 (Note 1 Test Circuit Figure 14) Output voltage (Vin = 30 V, ILoad = A, TJ = 25 C) voltage (18 V Vin 40 V, A ILoad A)VoutVTJ = 25 = 40 to +125 (Vin = 18 V, ILoad = A) 88 % LM2575 Adjustable VERSION (Note 1 Test Circuit Figure 14)Feedback voltage (Vin = 12 V, ILoad = A, Vout = V, TJ = 25 C) voltage ( V Vin 40 V, A ILoad A, Vout = V)VFBVTJ = 25 = 40 to +125 (Vin = 12 V, ILoad = A, Vout = V) 77 %1.

7 External components such as the catch diode, inductor, input and Output capacitors can affect switching regulator system the LM2575 is used as shown in the Figure 14 test circuit, system performance will be as shown in system parameters Tested junction temperature range for the LM2575 and the NCV2575: Tlow = 40 C Thigh = +125 CLM2575, PARAMETERSELECTRICAL CHARACTERISTICS (Unless otherwise specified, Vin = 12 V for the V, V, and Adjustable version, Vin = 25 Vfor the 12 V version, and Vin = 30 V for the 15 V version. ILoad = 200 mA. For typical values TJ = 25 C, for min/max values TJ is theoperating junction temperature range that applies [Note 2], unless otherwise noted.)CharacteristicsSymbolMinTypMaxUni tALL Output voltage VERSIONSF eedback Bias Current (Vout = V Adjustable Version Only)IbnATJ = 25 C 25100TJ = 40 to +125 C 200 Oscillator Frequency Note 3fosckHzTJ = 25 C 52 TJ = 0 to +125 C47 58TJ = 40 to +125 C42 63 Saturation voltage (Iout = A Note 4)VsatVTJ = 25 C = 40 to +125 C Duty Cycle ( on ) Note 5DC9498 %Current Limit (Peak Current Notes 4 and 3)ICLATJ = 25 = 40 to +125 Leakage Current Notes 6 and 7, TJ = 25 CILmAOutput = 0 V = V Current Note 6 IQmATJ = 25 C = 40 to +125 C 11 Standby Quiescent Current (ON/OFF Pin = V ( off ))IstbymATJ = 25 C1580200TJ = 40 to +125 C 400ON/OFF Pin Logic Input Level (Test Circuit Figure 14)

8 VVout = 0 VVIHTJ = 25 TJ = 40 to +125 Vout = Nominal Output VoltageVILTJ = 25 C = 40 to +125 C Pin Input Current (Test Circuit Figure 14)mAON/OFF Pin = V ( off ), TJ = 25 CIIH 1530ON/OFF Pin = 0 V ( on ), TJ = 25 CIIL The oscillator frequency reduces to approximately 18 kHz in the event of an Output short or an overload which causes the regulated outputvoltage to drop approximately 40% from the nominal Output voltage . This self protection feature lowers the average dissipation of the IC bylowering the minimum duty cycle from 5% down to approximately 2%.4. Output (Pin 2) sourcing current. No diode, inductor or capacitor connected to Output Feedback (Pin 4) removed from Output and connected to 0 Feedback (Pin 4) removed from Output and connected to +12 V for the Adjustable , V, and V versions, and +25 V for the 12 V and15 V versions, to force the Output transistor off.

9 7. Vin = 40 , PERFORMANCE CHARACTERISTICS (Circuit of Figure 14)Vout, Output voltage CHANGE (%) , QUIESCENT CURRENT (mA)Vin, INPUT voltage (V)IO, Output CURRENT (A)TJ, JUNCTION TEMPERATURE ( C)Vin, INPUT voltage (V)INPUT- Output DIFFERENTIAL (V)TJ, JUNCTION TEMPERATURE ( C)Vsat, SATURATION voltage (V)SWITCH CURRENT (A)Vout, Output voltage CHANGE (%)Figure 2. Normalized Output VoltageTJ, JUNCTION TEMPERATURE ( C)Figure 3. Line RegulationVin = 20 VILoad = 200 mANormalized atTJ = 25 CFigure 4. Switch Saturation VoltageFigure 5. Current LimitFigure 6. Dropout VoltageFigure 7. Quiescent CurrentILoad = 200 mATJ = 25 V, V and Adj12 V and 15 V25 CVin = 25 VVout = VMeasured atGround PinTJ = 25 CILoad = 200 mAILoad = ADVout = 5%Rind = W125 C-40 = 200 mAILoad = ALM2575, (PIN 2)OUTPUTCURRENT(PIN 2)INDUCTOROUTPUTRIPPLEVOLTAGEVout, Output voltage Istby, STANDBY QUIESCENT CURRENT ( A) 100-50-5010 V-500100 ms/DIVIFB, FEEDBACK PIN CURRENT (nA)TJ, JUNCTION TEMPERATURE ( C)TJ, JUNCTION TEMPERATURE ( C) ms/DIVNORMALIZED FREQUENCY (%)TJ, JUNCTION TEMPERATURE ( C)Istby, STANDBY QUIESCENT CURRENT ( A) Figure 8.

10 Standby Quiescent CurrentVin, INPUT voltage (V)Figure 9. Standby Quiescent CurrentFigure 10. Oscillator FrequencyFigure 11. Feedback Pin CurrentFigure 12. Switching WaveformsFigure 13. Load Transient ResponseVin = 12 VVON/OFF = VTJ = 25 , LOAD CURRENT (A) = 12 VNormalized at 25 CAdjustableVersion OnlyCHANGE (mV)CURRENTLM2575, 14. Typical Test CircuitD11N5819L1330 mHOutput24 FeedbackCout330 mF/16 VCin100 mF/50 VLM2575 5153ON/OFFGNDVinLoadVoutRegulatedOutputV inUnregulatedDC V - 40 VD11N5819L1330 mHOutput24 FeedbackCout330 mF/16 VCin100 mF/50 VLM2575 Adjustable153ON/OFFGNDVinLoadVoutRegulat edOutputUnregulatedDC V - 40 Output voltage VersionsAdjustable Output voltage VersionsVout+Vref 1) R2R1 R2+R1 VoutVref )1 Where Vref = V, R1 between kW and kWR2R1+-+-PCB LAYOUT GUIDELINESAs in any switching regulator, the layout of the printedcircuit board is very important.