601-00506 Parallax

LM2940/LM2940C 1A Low Dropout Regulator February 2006 LM2940/LM2940C 1A Low Dropout Regulator momentarily exceed the specified maximum operating volt- General Description age, the regulator will automatically shut down to protect The LM2940/LM2940C positive voltage regulator features both the internal circuits and the load. The LM2940/ the ability to source 1A of output current with a dropout LM2940C cannot be harmed by temporary mirror-image in- voltage of typically 0.5V and a maximum of 1V over the sertion. Familiar regulator features such as short circuit and entire temperature range. Furthermore, a quiescent current thermal overload protection are also provided. reduction circuit has been included which reduces the ground current when the differential between the input volt- Features age and the output voltage exceeds approximately 3V. The n Dropout voltage typically 0.5V I =1A quiescent current with 1A of output current and an input- O output differential of 5V is therefore only 30 mA. Higher n Output current in excess of 1A quiescent currents only exist when the regulator is in the n Output voltage trimmed before assembly dropout mode (V V 3V). IN OUT n Reverse battery protection Designed also for vehicular applications, the LM2940/ n Internal short circuit current limit LM2940C and all regulated circuitry are protected from re- n Mirror image insertion protection verse battery installations or 2-battery jumps. During line + n P Product Enhancement tested transients, such as load dump when the input voltage can Typical Application 00882203 *Required if regulator is located far from power supply filter. **C must be at least 22 F to maintain stability. May be increased without bound to maintain regulation during transients. Locate as close as possible OUT 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 Output Voltage Package Range 5.0 8.0 9.0 10 12 15 0C T 125C LM2940CT-5.0 LM2940CT-9.0 LM2940CT-12 LM2940CT-15 TO-220 J LM2940CS-5.0 LM2940CS-9.0 LM2940CS-12 LM2940CS-15 TO-263 LM2940CSX-5.0 LM2940CSX-9.0 LM2940CSX-12 LM2940CSX-15 40C T LM2940LD-5.0 LM2940LD-8.0 LM2940LD-9.0 LM2940LD-10 LM2940LD-12 LM2940LD-15 LLP J 125C 1k Units Tape and Reel LM2940LDX-5.0 LM2940LDX-8.0 LM2940LDX-9.0 LM2940LDX-10 LM2940LDX-12 LM2940LDX-15 LLP 4.5k Units Tape and Reel 40C T LM2940T-5.0 LM2940T-8.0 LM2940T-9.0 LM2940T-10 LM2940T-12 TO-220 J 125C LM2940S-5.0 LM2940S-8.0 LM2940S-9.0 LM2940S-10 LM2940S-12 TO-263 LM2940SX-5.0 LM2940SX-8.0 LM2940SX-9.0 LM2940SX-10 LM2940SX-12 40C T LM2940IMP-5.0 LM2940IMP-8.0 LM2940IMP-9.0 LM2940IMP-10 LM2940IMP-12 LM2940IMP-15 SOT-223 J 85C LM2940IMPX-5.0 LM2940IMPX-8.0 LM2940IMPX-9.0 LM2940IMPX-10 LM2940IMPX-12 LM2940IMPX-15 SOT-223 in Tape and Reel Marking L53B L54B L0EB L55B L56B L70B 2006 National Semiconductor Corporation DS008822 www.national.comOrdering Information (Continued) 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. Temperature Output Voltage Package Range 5.0 8.0 12 15 55C T 125C LM2940J-5.0/883 LM2940J-12/883 LM2940J-15/883 J16A J 5962-8958701EA 5962-9088401QEA 5962-9088501QEA LM2940WG5.0/883 LM2940WG5-12/883 LM2940WG5-15/883 WG16A 5962-8958701XA For information on military temperature range products, please go to the Mil/Aero Web Site at