MIC3202/MIC3202-1
High-Brightness LED Driver with
Integrated MOSFET and High-Side
Current Sense
944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.comMicrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408)
Septembe M9999-091710-A
r 2010
General Description
The MIC3202 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 MIC3202 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 MIC3202 offers a dedicated PWM input (DIM) which
enables a wide range of pulsed dimming. High-frequency
switching operation of up to 1MHz allows the use of
smaller external components, minimizing space and cost.
The MIC3202 offers a frequency dither feature for low-EMI
applications.
The MIC3202 operates over a junction temperature from
− ° + °40 C to 125 C and is available in an 8-pin e-PAD SOIC
package.
A dither disabled version MIC3202-1 is also available in
the same package as the MIC3202.
Datasheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Features
• 6V to 37V input voltage range
• > High efficiency ( 90%)
• ± 5% LED current accuracy
• MIC3202: Dither enabled for low EMI
• MIC3202-1: Dither disabled
• High-side current sense (up to 1A)
• Dedicated dimming control input
• Hysteretic control (no compensation required)
• Up to 1MHz 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
• 12V lighting systems (MR-16 bulbs, under-cabinet
lighting, garden/pathway lighting)
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Typical Application
MIC3202 Step-Down LED Driver
Efficiency
vs. Input Voltage
80
85
90
95
100
6 14 22 30 38
INPUT VOLTAGE (V)
EFFICIENCY (%)
I
LED
= 1A
L = 47uH
8LED6LED
4LED
2LED
