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LED Lighting Solutions Design Guide

11

LED Lighting Solutions

MCP1630 and MCP1631 High-Speed

PWM Controllers

The MCP1630 and MCP1631 offer another method that can

be used to generate high speed PWM signals for high power

LED drivers. The MCP1630 is an 8-pin device that contains

the components needed to generate an analog PWM control

loop, including an error amplifier, comparator and a high

current output pin to drive a power transistor.

The MCP1630 is designed to be used with a MCU that

provides a reference clock source. The MCU controls the

PWM frequency and maximum duty cycle. The switching

frequency can be up to 1 MHz, depending on the application

requirements. The MCU can also control the reference input

for the error amplifier when dimming or soft start functions

are required. Multiple MCP1630 devices can be attached to

a MCU to support multiple power channels.

The MCP1630 can be used to solve advanced power supply

issues. When multiple MCP1630 devices are used, phase

offsets can be applied to each clock input to reduce bus

current ripple. For applications that are sensitive to EMI,

dithering can be applied to the clock signal to reduce

radiated energy at a given frequency.

The MCP1631 is a 20-pin device which, in addition to

the MCP1630 includes an internal 5V or 3.3V regulator,

shutdown control, overvoltage protection, oscillator disable

and 1x and 10x gain amplifiers.

MCP1630 Boost Mode LED Driver

This demo board is a step-up, switch-mode,

DC-DC converter used for power LED

applications. The demo board provides a

350 mA or 700 mA constant current source

with a jumper selection. The input operating

voltage range is 9-16 VDC and the board

can supply up to 30W to a string of power

LEDs.

MCP1631HV Digitally Controlled Programmable

This board provides a SEPIC DC-DC

converter for power LED and battery

charging applications. The input voltage

range is 3.5-16 VDC and the maximum

power output is 8.5W.

Literature on the Web

Current Feedback

Thermal Feedback

PIC12HV615

MCU

MCP1630

PWM

Controller

5V

5V

10 LED String

700 mA, 34V DC

User

Interface

9-13V DC

Clock

Reference

MCP9700

Temp Sensor

MCP1630 Boost Mode LED Driver