LM2576规格书

(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002 1 GENERAL DESCRIPTION FEATURES 3.3V,5V,12V,15V,and adjustable output versions Adjustable version output voltage range,1.23V to 37V(57V for HV version)4%max over line and load conditions Guaranteed 3A output current Wide input voltage range,40V up to 60V for HV version Requires only 4 external components 52 kHz fixed frequency oscillator TTL shutdown capability,low power standby mode High efficiency Uses readily available standard inductors Thermal shutdown and current limit protection APLICATIONS Simple high-efficiency step-down(buck)regulator Efficient pre-regulator for linear regulators On-card switching regulators The LM2576 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down(buck)switching regulator,capable of driving 3A load with excellent line and load regulation.These devices are available in fixed output voltages of 3.3V,5V,12V,15V,and an adjustable output versions.Requiring a minimum number of external components,these regulators are simple to use and include internal frequency compensation and a fixed-frequency oscillator.The LM2576 series offers a high-efficiency replacement for popular three-terminal linear regulators.It substantially reduces the size of the heat sink,and in some cases no heat sink is required.A standard series of inductors optimized for use with the LM2576 are available from several different manufacturers.This feature greatly simplifies the design of switch-mode power supplies.Other features include a guaranteed 4%tolerance on output voltage within specified input voltages and output load conditions,and 10%on the oscillator frequency.External shutdown is included,featuring 50 A(typical)standby current.The output switch includes cycle-by-cycle current limiting,as well as thermal shutdown for full protection under fault conditions.Note:The LM2576HV is not produced yet.Positive to negative converter(Buck-Boost)TYPICAL APPLICATION(Fixed Output Voltage Versions)7V-40V(60V for HV)UNREGULATED DC INPUT LM2576/LM2576HV-5.0+V IN+5V REGULATED OUTPUT 3A LOAD 1+C IN 3 GND ON/OFF OUTPUT 4 L1 100 H D1 1N5822 C OUT 10 0 0 F 100 F FEEDBACK 5+FIGURE 1.2 Shenzhen Developer microelectronics Co.,Ltd 2 BLOCK DIAGRAM 3.3V,R2=1.7K 5V,R2=3.1K 12V,R2=8.84K 15V,R2=11.3K For ADJ,Version R1=Open,R2=0 ORDERING INFORMATION Output Voltage Temperature Range 3.3 5.0 12 15 ADJ Package Type LM2576HVS-3.3 LM2576HVS-5.0 LM2576HVS-12 LM2576HVS-15 LM2576HVS-ADJ LM2576S-3.3 LM2576S-5.0 LM2576S-12 LM2576S-15 LM2576S-ADJ TO-263 LM2576HVT-3.3 LM2576HVT-5.0 LM2576HVT-12 LM2576HVT-15 LM2576HVT-ADJ-40 C TA 125 C LM2576T-3.3 LM2576T-5.0 LM2576T-12 LM2576T-15 LM2576T-ADJ TO-220 +CINCOUTFEED-BACK+14+-+DRIVER1.23VBAND-GAP REFERENCE52kHZOSCILLATORRESETTHERMALSHUTDOWNCURRENTLIMIT32L1LOADINTERNALREGULATORON/OFF5R2R11.0kFIXED GAIN ERROR AMPCOMPARATOR3 AMPSWITCHOUTPUTGNDVOUTD1ON/OFFVINUNREGULATEDDC INPUT(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd 3 Absolute Maximum Ratings(Note 1)Minimum ESD Rating(C=100pF,R=1.5 k)Lead Temperature(Soldering,10 Seconds)2 kV260 C Maximum Supply Voltage Operating Ratings LM2576 45V LM2576HV 63V Temperature Range ON/OFF Pin Input Voltage-0.3V V +VIN LM2576/LM2576HV-40 C TJ +125 C Output Voltage to Ground Supply Voltage (Steady State)-1V LM2576 40V Power Dissipation Internally Limited LM2576HV 60V Storage Temperature Range-65 C to+150 C Maximum Junction Temperature 150 C LM2576-3.3,LM2576HV-3.3 Electrical Characteristics Specifications with standard type face are for TJ=25 C,and those with boldface type apply over full Operating Temperature Range.Symbol Parameter Conditions LM2576-3.3 LM2576HV-3.3 Units(Limits)Typ Limit(Note 2)SYSTEM PARAMETERS(Note 3)Test Circuit Figure 2 VOUT Output Voltage VIN=12V,ILOAD=0.5A Circuit of Figure 2 3.3 3.234 3.366 V V(Min)V(Max)VOUT Output Voltage LM2576 6V VIN 40V,0.5A ILOAD 3A Circuit of Figure 2 3.3 3.168/3.135 3.432/3.465 V V(Min)V(Max)VOUT Output Voltage LM2576HV 6V VIN 60V,0.5A ILOAD 3A Circuit of Figure 2 3.3 3.168/3.135 3.450/3.482 V V(Min)V(Max)Efficiency VIN=12V,ILOAD=3A 75%(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd 4 LM2576-5.0,LM2576HV-5.0 Electrical Characteristics Specifications with standard type face are for TJ=25 C,and those with Figure 2 boldface type apply over full Operating Temperature Range.Symbol Parameter Conditions LM2576-5.0 LM2576HV-5.0 Units(Limits)Typ Limit(Note 2)SYSTEM PARAMETERS(Note 3)Test Circuit Figure 2 VOUT Output Voltage VIN=12V,ILOAD=0.5A Circuit of Figure 2 5.0 4.900 5.100 V V(Min)V(Max)VOUT Output Voltage LM2576 0.5A ILOAD 3A,8V VIN 40V Circuit of Figure 2 5.0 4.800/4.750 5.200/5.250 V V(Min)V(Max)VOUT Output Voltage LM2576HV 0.5A ILOAD 3A,8V VIN 60V Circuit of Figure 2 5.0 4.800/4.750 5.225/5.275 V V(Min)V(Max)Efficiency VIN=12V,ILOAD=3A 77%LM2576-12,LM2576HV-12 Electrical Characteristics Specifications with standard type face are for TJ=25 C,and those with boldface type apply over full Operating Temperature Range.Symbol Parameter Conditions LM2576-12 LM2576HV-12 Units(Limits)Typ Limit(Note 2)SYSTEM PARAMETERS(Note 3)Test Circuit Figure 2 VOUT Output Voltage VIN=25V,ILOAD=0.5A Circuit of Figure 2 12 11.76 12.24 V V(Min)V(Max)VOUT Output Voltage LM2576 0.5A ILOAD 3A,15V VIN 40V Circuit of Figure 2 12 11.52/11.40 12.48/12.60 V V(Min)V(Max)VOUT Output Voltage LM2576HV 0.5A ILOAD 3A,15V VIN 60V Circuit of Figure 2 12 11.52/11.40 12.54/12.66 V V(Min)V(Max)Efficiency VIN=15V,ILOAD=3A 88%(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd 5 LM2576-15,LM2576HV-15 Electrical Characteristics Specifications with standard type face are for TJ=25 C,and those with boldface type apply over full Operating Temperature Range.Symbol Parameter Conditions LM2576-15 LM2576HV-15 Units(Limits)Typ Limit(Note 2)SYSTEM PARAMETERS(Note 3)Test Circuit Figure 2 VOUT Output Voltage VIN=25,ILOAD=0.5A Circuit of Figure 2 15 14.70 15.30 V V(Min)V(Max)VOUT Output Voltage LM2576 0.5A ILOAD 3A,18 VIN 40V Circuit of Figure 2 15 14.40/14.25 15.60/15.75 V V(Min)V(Max)VOUT Output Voltage LM2576HV 0.5A ILOAD 3A,18 VIN 60V Circuit of Figure 2 15 14.40/14.25 15.68/15.83 V V(Min)V(Max)Efficiency VIN=18V,ILOAD=3A 88%LM2576-ADJ,LM2576HV-ADJ Electrical Characteristics Specifications with standard type face are for TJ=25 C,and those with boldface type apply over full Operating Temperature Range.Symbol Parameter Conditions LM2576-ADJ LM2576HV-ADJ Units(Limits)Typ Limit(Note 2)SYSTEM PARAMETERS(Note 3)Test Circuit Figure 2 VOUT Feedback Voltage VIN=12V,ILOAD=0.5A,VOUT=5V Circuit of Figure 2 1.230 1.217 1.243 V V(Min)V(Max)VOUT Feedback Voltage LM2576 0.5A ILOAD 3A,8V VIN 40V VOUT=5V Circuit of Figure 2 1.230 1.193/1.180 1.267/1.280 V V(Min)V(Max)VOUT Feedback Voltage LM2576HV 0.5A ILOAD 3A,8V VIN 60V,VOUT=5V Circuit of Figure 2 1.230 1.193/1.180 1.273/1.286 V V(Min)V(Max)Efficiency VIN=12V,ILOAD=3A,VOUT=5V 77%(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd 6 All Output Voltage Versions Electrical Characteristics Specifications with standard type face are for TJ=25 C,and those with boldface type apply over full Operating Temperature Range.Unless otherwise specified,VIN=12V for the 3.3V,5V,and Adjustable version,VIN=25V for the 12V version,and VIN=30V for the 15V version,ILOAD=500mA.Symbol Parameter Conditions LM2576-XX LM2576HV-XX Units(Limits)Typ Limit(Note 2)DEVICE PARAMETERS Ib Feedback Bias Current VOUT=5V(Adjustable Version Only)50 100/500 nA fO Oscillator Frequency(Note 8)52 47/42 58/63 kHz kHz(Min)kHz(Max)VSAT Saturation Voltage IOUT=3A(Note 4)1.4 1.8/2.0 V V(Max)DC Max Duty Cycle(ON)(Note 5)98 93%(Min)ICL Current Limit(Notes 4,8)5.8 4.2/3.5 6.9/7.5 A A(Min)A(Max)IL Output Leakage Current(Notes 6,7):Output=0V Output=-1V Output=-1V 7.5 2 30 mA(Max)mA mA(Max)IQ Quiescent Current(Note 6)5 10 mA mA(Max)ISTBY Standby Quiescent Current _ ON/OFF Pin=5V(OFF)50 200 A A(Max)(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd 7 All Output Voltage Versions Electrical Characteristics(Continued)Specifications with standard type face are for TJ=25 C,and those with boldface type apply over full Operating Temperature Range.Unless otherwise specified,VIN=12V for the 3.3V,5V,and Adjustable version,VIN=25V for the 12V version,and VIN=30V for the 15V version,ILOAD=500mA.Symbol Parameter Conditions LM2576-XX LM2576HV-XX Units(Limits)Typ Limit(Note 2)_ ON/OFF CONTROL VIH _ ON/OFF Pin VOUT=0V 1.4 2.2/2.4 V(Min)VIL Logic Input Level VOUT=Nominal Output Voltage 1.2 1.0/0.8 V(Max)IIH _ ON/OFF Pin Input Current _ ON/OFF Pin=5V(OFF)12 30 A A(Max)IIL _ ON/OFF Pin=0V(ON)0 10 A A(Max)Note 1:Absolute Maximum Ratings indicate limits beyond which damage to the device may occur.Operating Ratings indicate conditions for which the device is intended to be functional,but do not guarantee specific performance limits.For guaranteed specifications and test conditions,see the Electrical Characteristics.Note 2:All limits guaranteed at room temperature(standard type face)and at temperature extremes(bold type face).Note 3:External components such as the catch diode,inductor,input and output capacitors can affect switching regulator system performance.When the LM2576/LM2576HV is used as shown in the Figure 2 test circuit,system performance will be as shown in system parameters section of Electrical Characteristics.Note 4:Output pin sourcing current.No diode,inductor or capacitor connected to output.Note 5:Feedback pin removed from output and connected to 0V.Note 6:Feedback pin removed from output and connected to+12V for the Adjustable,3.3V,and 5V,versions,and+25V for the 12V and 15V versions,to force the output transistor OFF.Note 7:VIN=40V(60V for high voltage version).Note 8:The oscillator frequency reduces to approximately 11 kHz in the event of an output short or an overload which causes the regulated output voltage to drop approximately 40%from the nominal output voltage.This self protections feature lowers the average power dissipation of the IC by lowering the minimum duty cycle from 5%down to approximately 2%.(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd 8 Typical Performance Characteristics(Circuit of Figure 2)TJ=25CVIN=40VILOAD=3AILOAD=200mAVIN=12VNormalized at 25CILOAD=200mAILOAD=3A-55C25C150C15V OUT5VSWITCH CURRENT(A)INPUT VOLTAGE(V)JUNCTION TEMPERATURE(C)Switch SaturationVoltageEfficiencyOscilator FrequencyVIN=20VILOAD=500mANormalized atTJ=25CILOAD=500mATJ=25CILOAD=3AILOAD=1AILOAD=200mAL1=150 HRIND=0.13.3V,5V&ADJ12V&15VJUNCTION TEMPERATURE(C)INPUT VOLTAGE(V)JUNCTION TEMPERATURE(C)Normalized Output VoltageLine RegulationDropout VoltageVIN=40VVOUT=5VMeasured atGround PinTJ=25CVIN=25VVIN=12 VVON/OFF=5VILOAD=3AILOAD=200mAJUNCTION TEMPERATURE(C)INPUT VOLTAGE(V)JUNCTION TEMPERATURE(C)Standby Quiescent CurrentQuiescent CurrentCurrent Limit(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd 9 Typical Performance Characteristics(Circuit of Figure 2)(Continued)VOUT 1.23VILOAD=500mAILOAD=500mAAdjustable Version OnlyAdjustable Version OnlyVIN=7VVIN=40VILOAD=500mAVIN=7VAdjustable Version OnlyVIN=40VDUTY CYCLE(%)JUNCTION TEMPERATURE(C)Minimum Operating VoltageQuiescent Currentvs Duty CycleFeedback Voltagevs Duty CycleDUTY CYCLE(%)Adjustable Version OnlyJA=32C/WJA=37C/WJA=50C/WJA=73C/WMaximum Power Dissipation(TO-263)Feedback Pin CurrentAMBIENT TEMPERATURE(C)JUNCTION TEMPERATURE(C)(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd 10 Typical Performance Characteristics(Circuit of Figure 2)(Continued)Switching Waveforms Load Transient Response VOUT=15V A:Output Pin Voltage,50V/div B:Output Pin Current,2A/div C:Inductor Current,2A/div D:Output Ripple Voltage,50mV/div,AC-Coupled Horizontal Time Base:5 s/div 5s/divABCD100s/divOutputVoltageChangeLoadCurrent(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd 11 Test Circuit and Layout Guidelines As in any switching regulator,layout is very important.Rapidly switching currents associated with wiring inductance generate voltage transients which can cause problems.For minimal inductance and ground loops,the length of the leads indicated by heavy lines should be kept as short as possible.Single-point grounding(as indicated)or ground plane construction should be used for best results.When using the Adjustable version,physically locate the programming resistors near the regulator,to keep the sensitive feedback wiring short.Fixed Output Voltage Versions CIN#100 F,75V,Aluminum Electrolytic COUT#1000 F,25V,Aluminum Electrolytic D1#Schottky,MBR360 L1#100 H,Pulse Eng.PE-92108 R1#2k,0.1%R2#6.12k,0.1%Adjustable Output Voltage Version )RR1(VV12REFOUT)1VV(RRREFOUT12 where VREF=1.23V,R1 between 1k and 5k FIGURE 2.7V-60VUNREGULATED DC INPUTLM2576HV-ADJ+VINLOAD1+CIN3GNDON/OFFOUTPUT4L1100 HD1MBR360COUT1000 F100 FFEEDBACK5+2VOUT5.00VR2R1VINUNREGULATED DC INPUTLM2576HV-FIXED OUTPUT+VINLOAD1+CIN3GNDON/OFFOUTPUT4L1100 HD1MBR360COUT1000 F100 FFEEDBACK5+2VOUT(LM2576-3.3)(LM2576HV-3.3)(LM2576-5.0)(LM2576HV-5.0)(LM2576-12)(LM2576HV-12)(LM2576-15)(LM2576HV-15)(LM2576-ADJ)(LM2576HV-ADJ)SIMPLE SWITCHER 3AStep-Down Voltage RegulatorMay 2001-revised July 2002Shenzhen Developer microelectronics Co.,Ltd