LM2991 Negative Low Dropout Adjustable Regulator
May 1999
LM2991 Negative Low Dropout Adjustable Regulator
General Des...
LM2991 Negative Low Dropout Adjustable Regulator
May 1999
LM2991 Negative Low Dropout Adjustable Regulator
General Description
The LM2991 is a low dropout adjustable negative regulator with a output
voltage range between −3V to −24V. The LM2991 provides up to 1A of load current and features a On /Off pin for remote shutdown capability. The LM2991 uses new circuit design techniques to provide a low dropout
voltage, low quiescent current and low temperature coefficient precision reference. The dropout
voltage at 1A load current is typically 0.6V and a guaranteed worst-case maximum of 1V over the entire operating temperature range. The quiescent current is typically 1 mA with a 1A load current and an input-output
voltage differential greater than 3V. A unique circuit design of the internal bias supply limits the quiescent current to only 9 mA (typical) when the regulator is in the dropout mode (VOUT − VIN ≤ 3V). The LM2991 is short-circuit proof, and thermal shutdown includes hysteresis to enhance the reliability of the device when inadvertently overloaded for extended periods. The LM2991 is available in 5-lead TO-220 and TO-263 packages and is rated for operation over the automotive temperature range of −40˚C to +125˚C. Mil-Aero versions are also available.
Features
n Output
voltage adjustable from −3V to −24V, typically −2V to −25V n Output current in excess of 1A n Dropout
voltage typically 0.6V at 1A load n Low quiescent current n Internal short circuit current limit n In...