General Description

The MCP16361/2/3 family of devices are highly integrated, high-efficiency, fixed-frequency, step-down DC-DC converters in a compact 8-lead 3x3 mm VDFN package that operates from input voltage sources up to 48V. Integrated features include a high-side switch, fixed-frequency Peak Current Mode Control, Internal Compensation, Power Good, Peak Current Limit and Overtemperature Protection. The MCP16361/2/3 provides all the active functions for local DC-DC conversion, with fast transient response and accurate regulation.

High efficiency conversion is achieved by integrating the current-limited, low-resistance, high-speed N-Channel MOSFET and associated drive circuitry. High switching frequency minimizes the size of external filtering components resulting in a small size solution.

The MCP16361/2/3 can supply 3A of continuous current while regulating the output voltage from 2.0V to 24V. An integrated, high-performance peak current mode architecture keeps the output voltage tightly regulated, even during input voltage steps and output current transient conditions that are common in power systems.

The MCP16361 is capable of running in PFM/PWM mode. It switches in PFM mode for light load conditions and for large buck conversion ratios. This results in a higher efficiency over all load ranges.

By comparison, the MCP16362 runs in PWM-only mode, and is recommended for applications in which the low-frequency component associated with PFM mode of operation is not desirable.

Besides the two aforementioned options, the MCP16363 is designed for EMI constrained applications where reduced peak emissions are required. This is achieved by sweeping the switching frequency over a 10 range above the 2.2 MHz nominal value.

Output voltage is set with an external resistor divider. The Power Good output pin will go from logic low to logic high (through an external pull-up resistor) once the output voltage is within 93 of the nominal set point. The EN input is used to turn the device on and off. While off, only a few micro-amps of current are consumed from the input.

The MCP16361/2/3 is offered in a space-saving 8-lead 3x3 mm VDFN wettable flanks surface mount package.

Features

•Input Voltage Range: 4.0V to 48V

•Adjustable Output Voltage Range: 2.0V to 24V

•Integrated N-Channel Buck Switch: 100 m

•3A Output Current

•2.2 MHz Fixed Frequency

•Shutdown Current: 5 μA typical

•Quiescent Current: 18 μA typical (not switching)

•Device Selectable Switching Mode

-Automatic Pulse Frequency Modulation/Pulse Width Modulation (PFM/PWM) Operation - MCP16361

-PWM only Mode of Operation - MCP16362

-PWM only Mode of Operation with Switching Frequency Dithering for EMI constrained applications - MCP16363

•Power Good Output

•Undervoltage Lockout (UVLO)

•Peak Current Mode Control

•Internal Compensation

•Internal Soft-Start

•Internal Bootstrap Diode

•Cycle-by-Cycle Peak Current Limit

•Overtemperature Protection

•Available Package: 8-lead 3x3 mm wettable flanks VDFN (see Package Type)

Applications

•Automotive DC/DC and 48V Systems

•Microcontroller Bias Supply

•24V Industrial Input DC-DC Conversion

•Set-Top Boxes, DSL Cable Modems

•Wall Cube Regulation

•SLA Battery-Powered Devices

•AC-DC Digital Control Power Sources

•Power Meters

•Medical and Health Care

•Distributed Power Supplies