The MIC5239 is a low quiescent current, µCap low-dropout regulator. With a maximum operating input voltage of 30V and a quiescent current of 23µA, it is ideal for supplying keep-alive power in systems with high voltage batteries. Capable of 500mA output, the MIC5239 has a dropout voltage of only 350mV. It can provide high output current for applications such as USB. As a µCap LDO, the MIC5239 is stable with either a ceramic or a tantalum output capacitor. It only requires a 3.3µF output capacitor for stability. The MIC5239 includes a logic compatible enable input and an undervoltage error flag indicator. Other features of the MIC5239 include thermal shutdown, current limit, overvoltage shutdown, reverse-leakage protection, and reverse-battery protection. Available in the thermally enhanced SOIC-8, MSOP-8 and SOT-223, the MIC5239 comes in fixed 1.5V, 1.8V, 2.5V, 3.0V, 3.3V and 5.0V, and adjustable voltages. For other output voltages, contact Micrel. All support documentation can be found on Micrel’s web site at: www.micrel.com.
The MIC5239 is a low‑quiescent current, uCap low‑dropout regulator designed for high‑voltage battery systems and USB power supplies. It operates from 2.3 V to 30 V, delivers up to 500 mA, and features a 350 mV dropout at full load.
The device is available in fixed‑voltage versions (1.5 V, 1.8 V, 2.5 V, 3.0 V, 3.3 V, 5.0 V) and an adjustable version, in SC‑8, MSOP‑8 and SOT‑223 packages. It includes a logic‑compatible enable pin, an undervoltage error flag, thermal shutdown, current limit, over‑voltage protection, reverse‑leakage and reverse‑battery protection.
| Quiescent current | 23 µA |
|---|---|
| Maximum output current | 500 mA |
| Dropout voltage (500 mA) | 350 mV |
| Input voltage range | 2.3 V to 30 V |
| Fixed output voltage options | 1.5 V, 1.8 V, 2.5 V, 3.0 V, 3.3 V, 5.0 V |
The MIC5239 can deliver up to 500 mA of continuous output current.
The device has an ultra‑low quiescent current of 23 µA.
At a 500 mA load the dropout voltage is only 350 mV.
It operates with an input voltage from 2.3 V up to 30 V.