The MIC23031 is a 400mA 4MHz switching regulator featuring HyperLight Load? mode. The MIC23031 is highly efficient throughout the entire output current range, drawing just 21μA of quiescent current in operation. The tiny 1.6 x 1.6mm MLF? package in combination with the 4MHz switching frequency enables a compact sub-1mm height solution with only three external components. The MIC23031 provides accurate output voltage regulation under the most demanding conditions responding extremely quickly to a load transient with exceptionally small output voltage ripple.
Factoring in the output current, the internal circuitry of the MIC23031 automatically selects between two modes of operation for optimum efficiency. Under light load conditions, the MIC23031 goes into HyperLight Load? mode. HyperLight Load? uses a Pulse-Frequency Modulation (PFM) control scheme that controls the off time at light load. This proprietary architecture reduces the amount of switching needed at light loads, thereby increasing operating efficiency. The MIC23031 attains up to 88% efficiency at 1mA output load. As the load current increases beyond approximately 100mA, the device operates using the Pulse-Width Modulation (PWM) method for up to 93% efficiency at higher loads. The two modes of operation ensure the highest efficiency across the entire load range.
The MIC23031 operates from an input voltage range of 2.7V to 5.5V and features internal power MOSFETs that deliver up to 400mA of output current. This step-down regulator provides an output voltage accuracy of +/-2.5% across the junction temperature range of -40oC to +125oC. The MIC23031 is available in fixed or adjustable versions supporting an output voltage as low as 0.7V.
Requirements
The MIC23031 evaluation board requires an input power source that is able to deliver greater than 500mA at 2.7V to the MIC23031. The output load can either be an active (electronic) or passive (resistive) load.