LM2576 3.0 A, 15 V, StepDown Switching Regulator The LM2576 series of regulators are monolithic integrated circuits ideally suited for easy and convenient design of a stepdown switching regulator (buck converter). All circuits of this series are LM2576 Typical Application (Fixed Output Voltage Versions) Feedback 4 L1 7.0 V 40 V +V in LM2576 100 H Unregulated Output 1 DC Input 5.0 V Regulated C in Output 3.0 A Load D1 2 100 F C out 3OGN 5N/OFF 1N5822 1000 F D Representative Block Diagram and Typical Application +V in ON/OFF Unregulated 3.1 V Internal Output R2 /OFF ON DC Input Regulator Voltage Versions ( ) 1 5 C 3.3 V 1.7 k in 5.0 V 3.1 k 4 12 V 8.84 k 15 V 11.3 k Feedback Current For adjustable version Limit R2 Fixed Gain R1 = open, R2 = 0 Error Amplifier Comparator Driver Regulated R1 Output Latch Freq 1.0 k L1 V out Shift Output 18 kHz 1.0 Amp 2 1.235 V Switch GND C D1 out BandGap Thermal 52 kHz 3 Reset Load Reference Oscillator Shutdown This device contains 162 active transistors. Figure 1. Block Diagram and Typical Application MAXIMUM RATINGS Rating Symbol Value Unit Maximum Supply Voltage V 45 V in ON/OFF Pin Input Voltage 0.3 V V +V V in Output Voltage to Ground (SteadyState) 1.0 V Power Dissipation Case 314B and 314D (TO220, 5Lead) P Internally Limited W D Thermal Resistance, JunctiontoAmbient R 65 C/W JA Thermal Resistance, JunctiontoCase R 5.0 C/W JC 2 Case 936A (D PAK) P Internally Limited W D Thermal Resistance, JunctiontoAmbient R 70 C/W JA Thermal Resistance, JunctiontoCase R 5.0 C/W JC Storage Temperature Range T 65 to +150 C stg Minimum ESD Rating (Human Body Model: C = 100 pF, R = 1.5 k ) 2.0 kV Lead Temperature (Soldering, 10 seconds) 260 C Maximum Junction Temperature T 150 C J Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied, damage may occur and reliability may be affected.