MIC4576-3.3WU-TR

The MIC4576 is a series of easy-to-use fixed and adjustable BiCMOS step-down (buck) switch-mode voltage regulators. The 200 kHz MIC4576 duplicates the pinout and function of the 52 kHz LM2576. The higher switching frequency may allow up to a 2:1 reduction in output filter inductor size. The MIC4576 is available in 3.3V, and 5V fixed output versions or a 1.23V to 33V adjustable output version. Both versions are capable of driving a 3A load with excellent line and load regulation. The feedback voltage is guaranteed to ±2% tolerance for adjustable versions, and the output voltage is guaranteed to ±3% for fixed versions, within specified voltages and load conditions. The oscillator frequency is guaranteed to ±10%. In Shutdown mode, the regulator draws less than 200 μA shutdown current. The regulator performs cycle-by-cycle current limiting and thermal shutdown for protection under fault conditions. This series of simple switch-mode regulators requires a minimum number of external components and can operate using a standard series of inductors. Frequency compensation is provided internally. The MIC4576 is available in TO-220 (T) and TO-263 (U) packages for the industrial temperature range.

Applications

• Simple High-Efficiency Step-Down (Buck) Regulator
• Efficient Preregulator for Linear Regulators
• On-Card Switching Regulators
• Positive-to-Negative Converter (Inverting Buck-Boost)
• Battery Charger
• Negative Boost Converter
• Step-Down to 3.3V for Intel Pentium and Similar Microprocessors

Key features

• Fixed 200 kHz Operation
• 3.3V, 5V, and Adjustable Output Versions
• Voltage Over Specified Line and Load Conditions: - Fixed version: ±3% maximum output voltage - Adjustable version: ±2% maximum feedback voltage
• Guaranteed 3A Switch Current
• Wide 4V to 36V Input Voltage Range
• Wide 1.23V to 33V Output Voltage Range
• Requires Minimum External Components
• <200 μA Typical Shutdown Mode
• 75% Efficiency (Adjustable Version >75% Typical)
• Standard Inductors are 25% of Typical LM2576 Inductor Values
• Thermal Shutdown
• Overcurrent Protection
• 100% Electrical Thermal Limit Burn-In