MIC3202/MIC3202-1

High-Brightness LED Driver with

Integrated MOSFET and High-Side

Current Sense

Micrel 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

1422

3038

INPUT VOLTAGE (V)

L = 47uH

8LED

6LED

4LED

2LED