MCP1633 Pulse-Width Modulation (PWM) Controller

The MCP1633 high-speed PWM controller from Microchip Technology is a pulse-width modulator developed for standalone power supply applications. The MCP1633 design is based on the MCP1632 PWM controller but includes specific blocks for PWM LED dimming. It is suitable for use in topologies requiring a low-side MOSFET, such as boost, flyback, SEPIC, Cuk, and more. The MCP1633 uses current mode control to provide superior bandwidth and transient response, and also cycle-by-cycle current limiting with adjustable peak offset. The MCP1633 is also capable of operating in voltage mode control if required.

The MCP1633 SEPIC LED driver demo board is a step-up/step-down, switch-mode, DC/DC converter used for LED driver applications. The demo board provides a 200 mA constant current source. Other output currents can be obtained with minor modifications to the board’s bill of materials (BOM). MCP1633 LED driver demo board utilizes Microchip's MCP1633 high-speed pulse-width modulator (PWM). The small 16-pin QFN MCP1633 device contains all the analog components necessary for a peak current mode control loop including specialized LED driver blocks. An 8-pin PIC12F1822 microcontroller is used to implement the dimming and protection functions. MCP1633 LED drivers are well suited for LED lighting, switch-mode power supply, and brick DC/DC converter applications.