LM340 Datasheet | National Semiconductor

Description The LM140/LM340A/LM340/LM78XXC monolithic 3-terminal positive voltage regulators employ internal current-limiting, thermal shutdown and safe-area pensa- tion, making them essentially indestructible. If adequate heat sinking is provided, they can deliver over 1.0A output cur- rent. They are intended as fixed voltage regulators in a wide range of applications including local (on-card) regulation for elimination of noise and distribution problems associated with single-point regulation. In addition to use as fixed volt- age regulators, these devices can be used with external ponents to obtain adjustable output voltages and cur- rents. Considerable effort was expended to make the entire series of regulators easy to use and minimize the number of external ponents. It is not necessary to bypass the output, although this does improve transient response. Input bypassing is needed only if the regulator is located far from the filter capacitor of the power supply. The 5V, 12V, and 15V regulator options are available in the steel TO-3 power package. The LM340A/LM340/LM78XXC series is available in the TO-220 plastic power package, and the LM340-5.0 is available in the SOT-223 package, as well as the LM340-5.0 and LM340-12 in the surface-mount TO263 package. Features n plete specifications at 1A load n Output voltage tolerances of ±2% at Tj = 25˚C and ±4% over the temperature range (LM340A) n Line regulation of 0.01% of VOUT/V of ∆VIN at 1A load (LM340A) n Load regulation of 0.3% of VOUT/A (LM340A) n Internal thermal overload protection n Internal short-circuit current limit n Output transistor safe area protection n P+ Product Enhancement tested Typical Applications Fixed Output Regulator Adjustable Output Regulator - Required if the regulator is located far from the power supply filter. - - Although no output capacitor is needed for stability, it does help transient response. (If needed, use 0.1 µF, ceramic disc). VOUT = 5V + (5V/R1 + IQ)...