High-Efficiency Step-Up (Boost) Converter Design Using the Microchip MCP1662T-E/OT

The demand for efficient power management solutions continues to grow, driven by the proliferation of battery-powered devices and energy-sensitive applications. Step-up (boost) converters are critical components in systems where the input voltage is lower than the required output voltage. The Microchip MCP1662T-E/OT is a highly integrated, high-efficiency boost converter controller designed to address these needs with exceptional performance and compact form factor.

Key Features of the MCP1662T-E/OT

The MCP1662T-E/OT is a fixed-frequency, current-mode PWM controller optimized for boost topologies. It operates over a wide input voltage range from 2.0V to 5.5V, making it suitable for single-cell Li-ion, dual-cell alkaline, or NiMH battery applications. The device can deliver output voltages up to 30V and supports load currents up to 1.5A, depending on the external component selection. Its integrated high-side PMOS switch reduces external part count and simplifies board layout, while its 1.2MHz fixed switching frequency allows for the use of small inductors and capacitors, minimizing the overall solution size.

Design Considerations for High Efficiency

Achieving high efficiency in a boost converter requires careful attention to several design parameters. Inductor selection is critical; a low-DCR (DC resistance) inductor improves efficiency by reducing conductive losses. The output capacitor must have low ESR (equivalent series resistance) to minimize output voltage ripple and stabilize the control loop. Additionally, PCB layout plays a significant role in performance. Proper grounding, short trace lengths for high-current paths, and adequate thermal management are essential to reduce noise and switching losses.

The MCP1662T-E/OT incorporates several features to enhance efficiency. Pulse Frequency Modulation (PFM) mode at light loads reduces switching losses, extending battery life in portable applications. The device also includes internal soft-start to limit inrush current during startup, protecting the converter and load.

Typical Application Circuit

A typical boost converter design using the MCP1662T-E/OT includes the IC, an inductor, input and output capacitors, a diode, and feedback resistors to set the output voltage. The feedback network divides the output voltage to the internal error amplifier’s reference voltage of 1.2V. By selecting appropriate resistor values, the output voltage can be precisely adjusted. For example, to achieve a 12V output from a 3.7V Li-ion battery, the resistor ratio must be set to divide 12V down to 1.2V.

Performance and Efficiency

The MCP1662T-E/OT demonstrates peak efficiencies exceeding 95% under optimal conditions. This high efficiency is maintained across a wide load range, thanks to the seamless transition between PWM and PFM modes. The device’s current-mode control provides excellent line and load regulation, ensuring stable operation even with varying input voltages and output demands.

ICGOODFIND: The Microchip MCP1662T-E/OT is an excellent choice for designers seeking a compact, high-efficiency boost converter solution. Its integration, wide input range, and advanced control features make it ideal for portable electronics, IoT devices, and other applications where space and power efficiency are paramount.

Keywords:

Boost Converter, High Efficiency, MCP1662T-E/OT, Current-Mode PWM, Power Management