MCP1662 LED DRIVER
EVALUATION BOARD
USER’S GUIDE
2014 Microchip Technology Inc. DS50002285A-page 11
Chapter 1. Product Overview
1.1 INTRODUCTION
This chapter provides an overview of the MCP1662 and covers the following topics:
• MCP1662 Short Overview
• What is the MCP1662 LED Driver Evaluation Board?
• What the MCP1662 LED Driver Evaluation Board Kit Contains
1.2 MCP1662 SHORT OVERVIEW
The MCP1662 is a compact, battery operated, fixed frequency, step-up DC/DC con-
verter optimized as an LED constant current generator. This product provides an
easy-to-use power supply solution for LEDs, with a minimum number of external com-
ponents for applications powered by two-cell or three cell alkaline, NiCd or NiMH bat-
teries, one-cell Li-Ion or Li-Polymer batteries.
The MCP1662 is a boost device with PWM-only functionality that operates at a fixed
500 kHz switching frequency. The device has an operating input voltage range from
2.4V to 5.5V (with a typical undervoltage of 2.3V to start and 1.85V to stop). Compared
to its counterpart, the MCP1661, the reference voltage is only 300 mV in order to min-
imize the losses on the sense resistor and increase the overall efficiency of the appli-
cation.
The LED can be turned on and off with a variable duty cycle applied to the EN pin for
applications that require current dimming (variable lighting). Compared to its counter-
part, the MCP1661, which is designed to be a voltage source, the start-up time for the
MCP1662 has been decreased in order to obtain higher dimming frequencies.
The MCP1662 can supply up to 100 mA of current for a string of four white LEDs (LED
forward voltage of 3.2V) from a 3V or higher input voltage source. More detailed infor-
mation regarding the current capabilities of the MCP1662 are available in the data
sheet.
In order to obtain a compact solution, the device is available in a small 5-Lead SOT-23
and an 8-Lead 2X3 TDFN package.
