The Micrel MIC4721 is a high efficiency PWM buck (step-down) regulator that provides up to 1.5A of output current. The MIC4721 operates at 2MHz and has proprietary internal compensation that allows a closed loop bandwidth of over 200KHz. The low on-resistance internal p-channel MOSFET of the MIC4721 allows efficiencies up to 94%, reduces external components count and eliminates the need for an expensive current sense resistor. The MIC4721 operates from 2.7V to 5.5V input and the output can be adjusted down to 1V. The devices can operate with a maximum duty cycle of 100% for use in low-dropout conditions. The MIC4721 is available in the 10-pin MSOP package with a junction operating range from –40°C to +125°C. Data sheets and support documentation can be found on Micrel’s web site at: www.micrel.com.
The MIC4721 is a high‑efficiency 1.5 A PWM buck regulator that operates from 2.7 V to 5.5 V input and can deliver output voltages down to 1 V. It features an internal p‑channel MOSFET, up to 94 % efficiency, and a 2 MHz switching frequency with a 100 % maximum duty cycle.
The datasheet includes ordering information, pin functions, absolute maximum ratings, electrical characteristics, typical performance curves, functional diagrams, layout recommendations, a schematic with bill of materials, and package dimensions for the 10‑pin MSOP package.
| Supply Voltage Range | 2.7 V to 5.5 V |
|---|---|
| Maximum Output Current | 1.5 A |
| Efficiency | up to 94 % |
| Maximum Duty Cycle | 100 % |
| Switching Frequency | 2 MHz |
| Package | 10‑pin MSOP |
The device operates from 2.7 V to 5.5 V input.
It can supply up to 1.5 A of output current.
The regulator can achieve efficiencies up to 94 %.
The PGOOD pin pulls low when the output voltage is within ±10 % of the set regulation voltage.