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 inputoutput 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 voltage 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 n n n n n n n 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 00882203 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 Temperature Range 0 C TJ 125 C 40 C TJ 125 C 40 C TJ 125 C 40 C TJ 85 C SOT 223 Package Marking Output Voltage 5 0 8 0 9 0 10 12 Package 15 LM2940CT 5 0 LM2940CT 9 0 LM2940CT 12 LM2940CT 15 LM2940CS 5 0 LM2940CS 9 0 LM2940CS 12 LM2940CS 15 TO 263 LM2940LD 12 LM2940LD 15 LLP 1k Units Tape and Reel LM2940LDX 15 LLP 4 5k Units Tape and Reel LM2940LD 5 0 LM2940LD 8 0 LM2940LD 9 0 LM2940LD 10 LM2940LDX 5 0 LM2940LDX 8 0 LM2940LDX 9 0 LM2940LDX 10 LM2940LDX 12 LM2940T 5 0 LM2940T 8 0 LM2940T 9 0 LM2940T 10 LM2940T 12 LM2940S 5 0 LM2940S 8 0 LM2940S 9 0 LM2940S 10 LM2940S 12 LM2940IMP 5 0 LM2940IMP 8 0 LM2940IMP 9 0 LM2940IMP 10 LM2940IMP 12 TO 220 TO 263 LM2940IMP 15 LM2940IMPX 5 0 LM2940IMPX 8 0 LM2940IMPX 9 0 LM2940IMPX 10 LM2940IMPX 12 LM2940IMPX 15 L53B L54B L0EB L55B L56B TO 220 SOT 223 SOT 223 in Tape and Reel L70B 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 2003 National Semiconductor Corporation DS008822 www national com LM2940 LM2940C 1A Low Dropout Regulator January 2003 LM2940 LM2940C Ordering Information Temperature Range Continued Output Voltage 5 0 55 C TJ 125 C 8 0 LM2940J 5 0 883 5962 8958701EA Package 12 LM2940J 8 0 883 5962 9088301QEA 15 LM2940J 12 883 5962 9088401QEA LM2940J 15 883 5962 9088501QEA LM2940WG5 0 883 5962 8958701XA J16A 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 Plastic Package 3 Lead SOT 223 00882202 00882242 Front View Order Number LM2940CT 5 0 LM2940CT 9 0 LM2940CT 12 LM2940CT 15 LM2940T 5 0 LM2940T 8 0 LM2940T 9 0 LM2940T 10 or LM2940T 12 See NS Package Number TO3B Front View Order Part Number LM2940IMP 5 0 LM2940IMP 8 0 LM2940IMP 9 0 LM2940IMP 10 LM2940IMP 12 or LM2940IMP 15 See NS Package Number MP04A 16 Lead Ceramic Surface Mount Package WG 16 Lead Dual in Line Package J 00882244 00882243 Top View Order Number LM2940WG5 0 883 5962 8958701XA See NS Package Number WG16A Top View Order Number LM2940J 5 0 883 5962 8958701EA LM2940J 8 0 883 5962 9088301QEA LM2940J 12 883 5962 9088401QEA LM2940J 15 883 5962 9088501QEA See NS Package Number J16A www national com 2 LM2940 LM2940C Connection Diagrams Continued TO 263 Surface Mount Package 8 Lead LLP 00882211 Top View 00882212 Side View Order Number LM2940CS 5 0 LM2940CS 9 0 LM2940CS 12 LM2940CS 15 LM2940S 5 0 LM2940S 8 0 LM2940S 9 0 LM2940S 10 or LM2940S 12 See NS Package Number TS3B 00882246 Top View Order Number LM2940LD 5 0 LM2940LD 8 0 LM2940LD 9 0 LM2940LD 10 LM2940LD 12 LM2940LD 15 See NS Package Number LDC08A Pin 2 and pin 7 are fused to center DAP Pin 5 ans 6 need to be tied together on PCB board 3 www national com LM2940 LM2940C Absolute Maximum Ratings SOT 223 MP Package Note 1 ESD Susceptibility Note 3 If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications LM2940S T MP 100 ms 60V LM2940CS T 1 ms 45V 2 kV Operating Conditions Note 1 Input Voltage 26V Temperature Range Internal Power Dissipation Note 2 Maximum Junction Temperature Lead Temperature Time for Wave Soldering TO 263 S Package 260 C 4s 40 C TJ 85 C LM2940IMP 65 C TJ 150 C 260 C 10s 0 C TJ 125 C LM2940CT LM2940CS 150 C TO 220 T Package 40 C TJ 125 C LM2940T LM2940S Internally Limited Storage Temperature Range 260 C 4s LM2940J LM2940WG 55 C TJ 125 C LM2940LD 40 C TJ 125 C 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 8V LM2940 LM2940 883 Limit Limit Note 4 Note 5 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 VO 2V VIN 26V 5 00 LM2940 LM2940 883 Limit Limit Note 4 Note 5 Units 9 4V VIN 26V 8 00 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 IO 5 mA Load Regulation Output Impedance 50 mA IO 1A 100 mADC and 20 mArms 35 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 …
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