LM2940 LM2940C 1A Low Dropout Regulator General Description The LM2940 LM2940C positive voltage regulator features the ability to source 1A of output current with a dropout voltage of typically 0 5V and a maximum of 1V over the entire temperature range Furthermore a quiescent current reduction circuit has been included which reduces the ground current when the differential between the input voltage and the output voltage exceeds approximately 3V The quiescent current with 1A of output current and an input output differential of 5V is therefore only 30 mA Higher quiescent currents only exist when the regulator is in the dropout mode VIN VOUT 3V Designed also for vehicular applications the LM2940 LM2940C and all regulated circuitry are protected from reverse battery installations or 2 battery jumps During line transients such as load dump when the input voltage can momentarily exceed the specified maximum operating volt age the regulator will automatically shut down to protect both the internal circuits and the load The LM2940 LM2940C cannot be harmed by temporary mirror image insertion Familiar regulator features such as short circuit and thermal overload protection are also provided Features Dropout voltage typically 0 5V IO 1A Output current in excess of 1A Output voltage trimmed before assembly Reverse battery protection Internal short circuit current limit Mirror image insertion protection P Product Enhancement tested Typical Application 882203 Required if regulator is located far from power supply filter COUT must be at least 22 F to maintain stability May be increased without bound to maintain regulation during transients Locate as close as possible to the regulator This capacitor must be rated over the same operating temperature range as the regulator and the ESR is critical see curve Ordering Information Temp Range 0 C TJ 125 C Output Voltage Package 5 0 8 0 9 0 10 12 15 LM2940CT 5 0 LM2940CT 9 0 LM2940CT 12 LM2940CT 15 LM2940CS 5 0 LM2940CS 9 0 LM2940CS 12 LM2940CS 15 LM2940CSX 9 0 LM2940CSX 12 LM2940CSX 15 LM2940CSX 5 0 LM2940LD 5 0 LM2940LD 8 0 LM2940LD 9 0 LM2940LD 10 LM2940LD 12 40 C 40 C TO 263 LLP 1k Units LM2940LD 15 Tape and Reel TJ 125 C TO 220 LM2940LDX 5 0 LM2940LDX 8 0 LM2940LDX 9 0 LM2940LDX 10 LM2940LDX 12 LM2940LDX 15 LLP 4 5k Units Tape and Reel LM2940T 5 0 LM2940T 8 0 LM2940T 9 0 LM2940T 10 LM2940T 12 TO 220 TJ LM2940S 5 0 LM2940S 8 0 LM2940S 9 0 LM2940S 10 LM2940S 12 125 C LM2940SX 5 0 LM2940SX 8 0 LM2940SX 9 0 LM2940SX 10 LM2940SX 12 2007 National Semiconductor Corporation 8822 TO 263 www national com LM2940 LM2940C 1A Low Dropout Regulator January 2007 LM2940 LM2940C Temp Range 40 C TA Output Voltage 5 0 8 0 9 0 10 12 Package 15 LM2940IMP 5 0 LM2940IMP 8 0 LM2940IMP 9 0 LM2940IMP 10 LM2940IMP 12 LM2940IMP 15 SOT 223 85 C LM2940IMPX 5 0 LM2940IMPX 8 0 LM2940IMPX 9 0 LM2940IMPX 10 LM2940IMPX 12 LM2940IMPX 15 Marking L53B L54B L0EB L55B L56B L70B SOT 223 in Tape and Reel The physical size of the SOT 223 is too small to contain the full device part number The package markings indicated are what will appear on the actual device Mil Aero Ordering Information Temperature Range 55 C TJ 125 C Output Voltage Package 5 0 8 0 12 15 LM2940J 5 0 883 5962 8958701EA LM2940J 12 883 5962 9088401QEA LM2940J 15 883 5962 9088501QEA J16A LM2940WG5 0 883 5962 8958701XA LM2940WG5 12 883 LM2940WG5 15 883 WG16A For information on military temperature range products please go to the Mil Aero Web Site at http www national com appinfo milaero index html Connection Diagrams TO 220 T Plastic Package SOT 223 MP 3 Lead 882202 882242 Front View See NS Package Number TO3B Front View See NS Package Number MP04A 16 Lead Dual in Line Package J 16 Lead Ceramic Surface Mount Package WG 882243 882244 Top View See NS Package Number J16A Top View See NS Package Number WG16A TO 263 S Surface Mount Package LLP LD 8 Lead 882211 Top View 882246 882212 Side View See NS Package Number TS3B Pin 2 and pin 7 are fused to center DAP Pin 5 and 6 need to be tied together on PCB board Top View See NS Package Number LDC08A www national com 2 If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications LM2940S J WG T MP 100 ms Operating Conditions 60V LM2940CS T 1 ms Internal Power Dissipation 260 C 30s 235 C 30s 2 kV Input Voltage Temperature Range 45V 26V 40 C TJ 125 C LM2940T LM2940S Storage Temperature Range 40 C TA 85 C LM2940IMP 65 C TJ 150 C Soldering Temperature Note 3 TO 220 T Wave TO 263 S 0 C TJ 125 C LM2940CT LM2940CS Internally Limited 150 C Note 2 Maximum Junction Temperature Note 1 55 C TJ 125 C LM2940J LM2940WG 40 C TJ 125 C LM2940LD 260 C 10s 235 C 30s Electrical Characteristics VIN VO 5V IO 1A CO 22 F unless otherwise specified Boldface limits apply over the entire operating temperature range of the indicated device All other specifications apply for TA TJ 25 C Output Voltage VO Parameter Conditions 5V Typ LM2940 Limit Note 5 8V LM2940 883 Limit Note 6 Typ 6 25V VIN 26V Output Voltage Line Regulation 5 mA IO 1A 4 85 4 75 4 85 4 75 5 15 5 25 5 15 5 25 20 50 40 50 LM2940 LM2940 883 35 50 80 50 100 LM2940C 35 50 100 mADC and 20 mArms 35 VO 2V VIN 26V 5 00 LM2940 Limit Note 5 LM2940 883 Limit Note 6 Units 9 4V VIN 26V 7 76 7 60 7 76 7 60 VMIN 8 24 8 40 8 24 8 40 VMAX 20 80 50 80 mVMAX 55 80 130 80 130 mVMAX 55 80 1000 1000 m 8 00 IO 5 mA Load Regulation Output Impedance 50 mA IO 1A 1000 1000 55 15 20 10 15 20 15 20 mAMAX 50 60 30 45 60 50 60 mAMAX 700 700 240 1000 1000 Vrms fO 120 Hz Quiescent VO 2V VIN 26V Current IO 5 mA LM2940 LM2940 883 10 15 20 LM2940C 10 15 VIN VO 5V 30 45 60 IO 1A Output Noise 10 Hz 100 kHz Voltage IO 5 mA Ripple Rejection fO 120 Hz 1 Vrms 150 IO 100 mA LM2940 72 60 54 66 54 48 LM2940C 72 60 66 54 fO 1 kHz 1 Vrms 60 50 dBMIN 54 48 dBMIN IO 5 mA Long Term Stability Dropout Voltage 20 32 mV 1000 Hr IO 1A 0 5 0 8 1 0 0 7 1 0 0 5 0 8 1 0 0 7 1 0 VMAX IO 100 mA 110 150 200 150 200 110 150 200 150 200 mVMAX 3 www national com LM2940 LM2940C SOT 223 MP LLP 8 LD ESD Susceptibility Note 4 Absolute Maximum Ratings Note 1 LM2940 LM2940C Output Voltage VO Parameter 5V Conditions Short Circuit Current …
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