MIC3203 Datasheet, PDF (1/21 Pages) Micrel Semiconductor – High-Brightness LED Driver Controller with High-Side Current Sense

MIC3203/MIC3203-1
High-Brightness LED Driver Controller
with High-Side Current Sense
General Description
Features
The MIC3203 is a hysteretic, step-down, constant-current,
High-Brightness LED (HB LED) driver. It provides an ideal
solution for interior/exterior lighting, architectural and
ambient lighting, LED bulbs, and other general illumination
applications.
The MIC3203 is well suited for lighting applications
requiring a wide-input voltage range. The hysteretic control
gives good supply rejection and fast response during load
transients and PWM dimming. The high-side current
sensing and on-chip current-sense amplifier delivers LED
current with ±5% accuracy. An external high-side current-
sense resistor is used to set the output current.
The MIC3203 offers a dedicated PWM input (DIM) which
enables a wide range of pulsed dimming. A high-frequency
switching operation up to 1.5MHz allows the use of smaller
external components minimizing space and cost. The
MIC3203 offers frequency dither feature for EMI control.
The MIC3203 operates over a junction temperature from
−40°C to +125°C and is available in an 8-pin SOIC
package.
A dither disabled version MIC3203-1 is also available in
the same package as the MIC3203.
• 4.5V to 42V input voltage range
• High efficiency (>90%)
• ±5% LED current accuracy
• MIC3203: Dither enabled for low EMI
• MIC3203-1: Dither disabled
• High-side current sense
• Dedicated dimming control input
• Hysteretic control (no compensation!)
• Up to 1.5MHz switching frequency
• Adjustable constant LED current
• Over-temperature protection
• −40°C to +125°C junction temperature range
Applications
• Architectural, industrial, and ambient lighting
• LED bulbs
• Indicators and emergency lighting
• Street lighting
• Channel letters
Datasheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
• 12V lighting systems (MR-16 bulbs, under-cabinet
lighting, garden/pathway lighting)
_________________________________________________________________________________________________________________________
Typical Application
MIC3203 Step-down LED Driver
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
March 2010
M9999-032910-A