Microchip Technology

The MIC2129 is a constant-frequency synchronous buck controllers featuring a unique adaptive ON-time control architecture. The MIC2129 operates over an input voltage range from 4.5V to 100V and can be used to supply load current up to 25A (Thermally Limited) . The output voltage is adjustable down to 0.6V with an accuracy of ±1%. The device operates with programmable switching frequency from 100kHz to 800kHz. The MIC2129 controller offers three selectable gate drive voltages (5.2V, 7.5V, 10.5V) to enable the use of logic level or standard FETS to ensure optimal efficiency. The high voltage bootstrap diode is also integrated in this controller saving overall solution size and cost. The other key features of the MIC2129 are remote sense, integrated bootstrap LDO's, adjustable soft start, selectable light load operating modes, precision enable, selectable current limit modes (Hiccup, Latch-up, Cycle by cycle), output OVP protection, Power Good and thermal shut down. The MIC2129 is offered in a 24 pin QFN and as well as TSSOP packages.

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.*