MIC3230 Datasheet, PDF (1/20 Pages) Micrel Semiconductor – Constant Current Boost Controller for Driving High Power LEDs

MIC3230/1/2
Constant Current Boost Controller for
Driving High Power LEDs
Bringing the Power to Light™
General Description
The MIC3230/1/2 are constant current boost switching
controllers specifically designed to power one or more
strings of high power LEDs. The MIC3230/1/2 have an
input voltage range from 6V to 45V and are ideal for a
variety of solid state lighting applications.
The MIC3230/1/2 utilizes an external power device which
offers a cost conscious solution for high power LED
applications. The powerful drive circuitry can deliver up to
70W to the LED system. Power consumption has been
minimized through the implementation of a 250mV
feedback voltage reference providing an accuracy of ±3%.
The MIC323x family is dimmable via a pulse width
modulated (PWM) input signal and also features an enable
pin for low power shutdown.
Multiple MIC3230 ICs can be synchronized to a common
operating frequency. The clocks of these synchronized
devices can be used together in order 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 optimized for efficiency (performance) and size of the
external components (cost). The MIC323x family of LED
drivers also offer the following protection features: Over
voltage protection (OVP), thermal shutdown and under-
voltage lock-out (UVLO).
Features
• 6V to 45V input supply range
• Capable of driving up to 70W
• Ultra low EMI via dithering on the MIC3231
• Programmable LED drive current
• Feedback voltage = 250mV ±3%
• Programmable switching frequency (MIC3230/1) or
400kHz fixed frequency operation (MIC3232)
• PWM Dimming and separate enable shutdown
• Frequency synchronization with other MIC3230s
• Protection features:
Over Voltage Protection (OVP)
Over temperature protection
Under-voltage Lock-out (UVLO)
• Packages:
VIN 1
EN 2
PWMD 3
COMP 4
IADJ 5
10 VDD
9 DRV
8 PGND
7 OVP
6 IS
MIC3232
MSOP-10
VIN 1
EN 2
PWMD 3
COMP 4
IADJ 5
FS 6
EPAD
12 VDD
11 DRV
10 PGND
9 OVP
8 IS
7 SYNC/NC
MIC3230/1
MLF-12
N/C 1
VIN 2
16 N/C
15 VDD
EN 3
14 DRV
PWMD 4
COMP 5
13 PGND
12 OVP
IADJ 6
11 IS
FS 7
AGND 8
EPAD
10 SYNC/NC
9 N/C
MIC3230/1
TSSOP-16
• –40°C to +125°C junction temperature range
The MIC3231 offers a dither feature to assist in the
reduction of EMI. This is particularly useful in sensitive
EMI applications, and provides for a reduction or
emissions by approximately 10dB.
The MIC3232 is a 400kHz fixed frequency device offered
in a small MSOP-10 package. The MIC3230/1 are offered
in both the EPAD TSSOP-16 package and the
3mm × 3mm MLF^®-12 package.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Applications
• Street Lighting
• Solid State Lighting
• General Illumination
• Architectural Lighting
• Constant Current Power Supplies
_________________________________________________________________________________________________
Bringing the Power to Light is a trademark of Micrel, Inc.
MicroLead Frame and MLF are registered trademark of Amkor Technologies.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
January 2009
M9999-011409-A
[phone]