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High-Brightness LED Driver Controller with High-Side Current Sense
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 currentsense 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℃ to +125℃ and is available in an 8-pin SOIC package.
MIC3203 主要特性:
• 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℃ to +125℃ junction temperature range
MIC3203 应用:
• 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)
图1.MIC3203/MIC3203-1方框图
