The MIC39500 and MIC39501 is a 5A low-dropout linear voltage regulator that provides a low-voltage, high-current output with a minimum of external components. Utilizing Micrel's proprietary Super eta PNPTM pass element, the MIC39500 offers extremely low dropout (typically 400mV at 5A) and low ground current (typically 70mA at 5A). The MIC39500 is ideal for PC Add-In cards that need to convert from standard 5V or 3.3V, down to new, lower core voltages. A guaranteed maximum dropout voltage of 500mV over all operating conditions allows the MIC39500 to provide 2.5V from a supply as low as 3V. The MIC39500 also has fast transient response, for heavy switching applications. The device requires only 47F of output capacitance to maintain stability and achieve fast transient response The MIC39500 is fully protected with overcurrent limiting, thermal shutdown, reversed-battery and reversed-lead insertion protection. The MIC39501 offers a TTL-logic-compatible enable pin and an error flag that indicates undervoltage and overcurrent conditions. The MIC39500 comes in the TO220 and TO-263 packages and is an ideal upgrade to older, NPN-based linear voltage regulators.