POWER AND LINEAR IC SOLUTIONS

Constant-Current Boost Controller

Solid-state lighting is a growth market; it offers greater energy efficiency, longer operating lives and far more design flexibility than has ever been possible with traditional incandescent lamps. However, to get the most from these systems, suitable IC components are needed to drive them.

The MIC3230/1/2 devices from Micrel are constant-current boost switching controllers specifically designed to power one or more strings of high-power LED emitters. Suitable for a variety of solid-state lighting applications, these ICs have an input voltage range from 6V to 45V.



The powerful drive circuitry can deliver up to 70W to the LED system. Power consumption is minimised through the implementation of a 250mV feedback voltage reference providing an accuracy of ±3%. The devices in this family of drivers all have dimming capability via a Pulse Width Modulated (PWM) input signal and feature an enable pin for low-power shutdown.

Multiple MIC3230 ICs can be synchronised to a common operating frequency and work together to help reduce noise and errors in a system. An external resistor sets the adjustable switching frequency of the MIC3230/1.

The switching frequency can be between 100kHz and 1MHz. Setting the switching frequency provides the mechanism by which a design can be optimised for high efficiency or a reduced number of external components. The drivers also offer a variety of protection features, including overvoltage protection, thermal shutdown and undervoltage lockout.

The MIC3231 has a dither feature to assist in the reduction of ElectroMagnetic Interference (EMI). It lowers emission levels by approximately 10dB.

The MIC3232 is a 400kHz fixed frequency device in a small MSOP-10 package. The MIC3230 and MIC3231 both have programmable switching frequency and are available in EPAD TSSOP-16 and 3mm × 3mm MLF^®-12 packages.

Features

• 70W output power
• Operating temperature: –40°C to +125°C
• Wide input voltage range: 6V to 45V
• Switching frequency range: 100kHz to 1MHz
• Compact packages

Applications

• Architectural lighting
• Industrial lighting
• Display lighting
• General lighting
• Automotive lighting

For further information, including the Micrel MIC3230/1/2 Datasheet and Datasheets for the MIC3230/1 and MIC3232 Evaluation Boards, please click here

Note: MLF is a registered trademark of Amkor Technologies.