The LT83203/LT83205 synchronous step-down regulator is uniquely designed to combine an ultra-low noise reference with Silent Switcher architecture to achieve both high efficiency and excellent wideband noise performance. The innovative ultra-low noise architecture provides exceptional low-frequency (0.1Hz to 100kHz) output noise performance in a switching regulator. The output voltage can be programmed with a single resistor, resulting in virtually constant output noise independent of output voltage. Silent Switcher architecture minimizes EMI emissions while delivering high efficiency at high switching frequencies. The LT83203/LT83205 is ideal for high-current, noise-sensitive applications that benefit from the high efficiency of a synchronous switching regulator. APPLICATIONS * RF Power Supplies: PLLs, VCOs, Mixers, LNAs, PAs * High Speed/High Precision ADCs/DACs * Low Noise Instrumentation * General Purpose Power Supply * Silent Switcher® 3 Architecture * Ultra-Low RMS Noise (10Hz to 100kHz): 4μVRMS * Ultra-Low Spot Noise: 4nV/√Hz at 10kHz * Ultra-Low EMI Emissions * Ultra-Fast Transient Response * <1μs Transient Recovery Time * High Efficiency at High Frequency * Up to 93% Efficiency at 2MHz, 12VIN to 3.3VOUT * Up to 90% Efficiency at 4MHz, 12VIN to 3.3VOUT * Input Voltage Range: 2.8V to 18V * Output Voltage Range: 0V to (VIN − 0.5V) * Unity Gain Configuration up to 13V Output