The MIC2178 is a 200kHz synchronous buck (step-down) switching regulator designed for high-efficiency, battery-powered applications.The MIC2178 operates from a 4.5V to 16.5V input and features internal power MOSFETs that can supply up to 2.5A output current. It can operate with a maximum duty cycle of 100% for use in low-dropout conditions. It also features a shutdown mode that reduces quiescent current to less than 5µA.
The MIC2178 achieves high efficiency over a wide output current range by operating in either PWM or skip mode. The operating mode is externally selected, typically by an intelligent system, which chooses the appropriate mode according to operating conditions, efficiency, and noise requirements. The switching frequency is preset to 200kHz and can be synchronized to an external clock signal of up to 300kHz.
The MIC2178 uses current-mode control with internal current sensing. Current-mode control provides superior line regulation and makes the regulator control loop easy to compensate. The output is protected with pulse-by-pulse current limiting and thermal shutdown. Undervoltage lockout turns the output off when the input voltage is less than 4.5V.
The MIC2178 and is packaged in a 20-lead wide power SOIC package with an operating temperature range of -40°C to +85°C.
See the MIC2177 for automatic selection of PWM or skip-mode operation.