LM2937 500 mA Low Dropout Regulator General Description The LM2937 is a positive voltage regulator capable of supplying up to 500 mA of load current The use of a PNP power transistor provides a low dropout voltage characteristic With a load current of 500 mA the minimum input to output voltage differential required for the output to remain in regulation is typically 0 5V 1V guaranteed maximum over the full operating temperature range Special circuitry has been incorporated to minimize the quiescent current to typically only 10 mA with a full 500 mA load current when the input to output voltage differential is greater than 3V The LM2937 requires an output bypass capacitor for stability As with most low dropout regulators the ESR of this capacitor remains a critical design parameter but the LM2937 includes special compensation circuitry that relaxes ESR requirements The LM2937 is stable for all ESR below 3 This allows the use of low ESR chip capacitors Ideally suited for automotive applications the LM2937 will protect itself and any load circuitry from reverse battery connections two battery jumps and up to 60V 50V load dump transients Familiar regulator features such as short circuit and thermal shutdown protection are also built in Features n Fully specified for operation over 40 C to 125 C n Output current in excess of 500 mA n Output trimmed for 5 tolerance under all operating conditions n Typical dropout voltage of 0 5V at full rated load current n Wide output capacitor ESR range up to 3 n Internal short circuit and thermal overload protection n Reverse battery protection n 60V input transient protection n Mirror image insertion protection Connection Diagrams TO 220 Plastic Package SOT 223 Plastic Package 01128002 Front View 01128026 Front View TO 263 Surface Mount Package 01128006 Side View 01128005 Top View 2005 National Semiconductor Corporation DS011280 www national com LM2937 500 mA Low Dropout Regulator August 2005 LM2937 Ordering Information Package Temperature Range TO 263 40 C TJ 125 C Part Number Packaging Marking LM2937ES 5 0 LM2937ES 5 0 LM2937ESX 5 0 LM2937ES 8 0 LM2937ES 8 0 LM2937ES 10 LM2937ES 12 SOT 223 40 C TJ 125 C 40 C TJ 85 C Rail Rail Rail 500 Units Tape and Reel LM2937ET 5 0 LM2937ET 5 0 Rail LM2937ET 8 0 LM2937ET 8 0 Rail LM2937ET 10 LM2937ET 10 Rail LM2937ET 12 LM2937ET 12 Rail LM2937ET 15 LM2937ET 15 LM2937IMP 5 0 L71B LM2937IMPX 5 0 LM2937IMP 8 0 L72B LM2937IMPX 8 0 LM2937IMP 10 L73B LM2937IMPX 10 LM2937IMP 12 L74B LM2937IMPX 12 LM2937IMP 15 L75B LM2937IMPX 15 www national com Rail 500 Units Tape and Reel LM2937ES 15 LM2937ESX 15 TO 220 TS3B 500 Units Tape and Reel LM2937ESX 12 LM2937ES 15 Rail 500 Units Tape and Reel LM2937ESX 10 LM2937ES 12 NSC Drawing 500 Units Tape and Reel LM2937ESX 8 0 LM2937ES 10 Transport Media 2 TO3B Rail 1k Units Tape and Reel 2k Units Tape and Reel 1k Units Tape and Reel 2k Units Tape and Reel 1k Units Tape and Reel 2k Units Tape and Reel 1k Units Tape and Reel 2k Units Tape and Reel 1k Units Tape and Reel 2k Units Tape and Reel MP04A TO 263 10 seconds 230 C If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications SOT 223 Vapor Phase 60 seconds 215 C SOT 223 Infared 15 seconds 220 C ESD Susceptibility Note 3 2 kV Input Voltage Continuous 26V Transient t 100 ms 60V Internal Power Dissipation Note 2 Temperature Range Note 2 Internally Limited 150 C LM2937ET 65 C to 150 C LM2937IMP Maximum Junction Temperature Storage Temperature Range Operating Conditions Note 1 TO 220 10 seconds 40 C TJ 125 C LM2937ES 40 C TJ 85 C Maximum Input Voltage 260 C 26V Electrical Characteristics VIN VNOM 5V Note 4 IOUTmax 500 mA for the TO 220 and TO 263 packages IOUTmax 400mA for the SOT 223 package COUT 10 F unless otherwise indicated Boldface limits apply over the entire operating temperature range of the indicated device all other specifications are for TA TJ 25 C Output Voltage VOUT Parameter Output Voltage Conditions 5V Typ 5 mA IOUT IOUTmax 8V Limit Limit 8 00 7 60 4 85 5 00 4 75 10V Typ Limit 9 70 V Min 10 00 9 50 V Min 10 30 V Max 7 76 5 15 8 24 5 25 Units Typ 10 50 V Max 15 50 24 80 30 100 mV Max 5 mA IOUT IOUTmax 5 50 8 80 10 100 mV Max VOUT 2V VIN 26V 2 10 2 10 2 10 mA Max 10 20 10 20 10 20 mA Max Line Regulation VOUT 2V VIN 26V Load Regulation Quiescent Current 8 40 IOUT 5 mA IOUT 5 mA VIN VOUT 5V IOUT IOUTmax Output Noise 10 Hz 100 kHz Voltage IOUT 5 mA Long Term Stability 1000 Hrs Dropout Voltage 240 300 Vrms 20 32 40 mV IOUT IOUTmax 0 5 1 0 0 5 1 0 0 5 1 0 V Max IOUT 50 mA 110 250 110 250 110 250 mV Max 1 0 0 6 1 0 0 6 1 0 0 6 A Min 75 60 75 60 75 60 V Min 26 V Min Short Circuit Current Peak Line Transient 150 tf 100 ms RL 100 Voltage Maximum Operational 26 26 Input Voltage Reverse DC VOUT 0 6V RL 100 30 15 30 15 30 15 V Min tr 1 ms RL 100 75 50 75 50 75 50 V Min Input Voltage Reverse Transient Input Voltage 3 www national com LM2937 Absolute Maximum Ratings Note 1 LM2937 Electrical Characteristics VIN VNOM 5V Note 4 IOUTmax 500 mA for the TO 220 and TO 263 packages IOUTmax 400mA for the SOT 223 package COUT 10 F unless otherwise indicated Boldface limits apply over the entire operating temperature range of the indicted device all other specifications are for TA TJ 25 C Output Voltage VOUT Parameter Output Voltage 12V Conditions Typ 5 mA IOUT IOUTmax Typ 11 64 12 00 Line Regulation 15V Limit VOUT 2V VIN 26V 11 40 Units Limit 14 55 15 00 V Min 14 25 V Min 12 36 15 45 V Max 12 60 15 75 V Max 36 120 45 150 mV Max IOUT 5 mA Load Regulation 5 mA IOUT IOUTmax 12 120 15 150 mV Max Quiescent Current VOUT 2V VIN 26V 2 10 2 10 mA Max 10 20 10 20 mA Max IOUT 5 mA VIN VOUT 5V IOUT IOUTmax Output Noise 10 Hz 100 kHz Voltage IOUT 5 mA Long Term Stability 1000 Hrs Dropout Voltage IOUT IOUTmax 0 5 1 0 0 5 1 0 V Max IOUT 50 mA 110 250 110 250 mV Max 1 0 0 6 1 0 0 6 A Min 75 60 75 60 V Min 26 V Min Short Circuit Current Peak Line Transient tf 100 ms RL 100 360 450 Vrms 44 56 mV Voltage Maximum Operational 26 Input Voltage Reverse DC VOUT 0 6V RL 100 30 15 30 15 V Min …
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