Micrel’s MIC23250 is a dual 400-mA synchronous buck converter housed in a 2-mm x 2-mm, 10-lead MLF package. Aimed at portable applications, the MIC23250 uses the company’s “Hyper Light Load” switching method to achieve up to 94% peak efficiency, low output ripple, and fast transient response while using small output capacitors.
“The 2-mm x 2-mm package and 4-MHz switching speed, which allows the use of 1-µH to 2.2-µH inductors, equates to the smallest dual portable power solution on the market today,” says Andy Cowell, Micrel’s Vice President of Marketing for Analog at Micrel.
The regulator accepts an input voltage of 2.7 V to 5.5 V, and generates fixed, preset output voltages down to 0.72 V. Under normal loads, the MIC23250 switches at 4 MHz and runs in a continuous-conduction mode. The device automatically transitions to a variable-frequency Hyper Light Load mode during light-load conditions to maintain high efficiency.
Typical quiescent current is 35 µA with both regulators operating and efficiency is approximately 85% at a 1-mA load. In the full PWM mode, output voltage ripple is less than 3 mV, rising to 20 mVpp in Hyper Light Load mode. Unit pricing starts at $1.47 for 1000-piece quantities.