MIC2178 Micrel, Inc. MIC2178
2.5A Synchronous Buck Regulator General Description Features The Micrel MIC2178 is a 200kHz synchronous buck (stepdown) 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
5ВµA.
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
+85В°C.
See the MIC2177 for automatic selection of PWM or skipmode operation. 4.5V to 16.5V input voltage range Dual-mode operation for high efficiency (up to 96%)
PWM mode for > 200mA load current …
