LT1738

U U LT1738 Slew Rate Controlled Ultralow Noise DC/DC Controller FEATURES s Greatly Reduced Conducted and Radiated EMI s Low Switching Harmonic Content s Independent Control of Output Switch Voltage and Current Slew Rates s Greatly Reduced Need for External Filters s Single N-Channel MOSFET Driver s 20kHz to 250kHz Oscillator Frequency s Easily Synchronized to External Clock s Regulates Positive and Negative Voltages s Easier Layout Than with Conventional Switchers U APPLICATIO S s Power Supplies for Noise Sensitive Communication Equipment s EMI Compliant Offline Power Supplies s Precision Instrumentation Systems s Isolated Supplies for Industrial Automation s Medical Instruments s Data Acquisition Systems DESCRIPTIO The LT®1738 is a switching regulator controller designed to lower conducted and radiated electromagnetic interference (EMI). Ultralow noise and EMI are achieved by controlling the voltage and current slew rates of an external N-channel MOSFET switch. Current and voltage slew rates can be independently set to optimize harmonic content of the switching waveforms vs efficiency. The LT1738 can reduce high frequency harmonic power by as much as 40dB with only minor losses in efficiency. The LT1738 utilizes a current mode architecture optimized for single switch topologies such as boost, flyback and Cuk. The IC includes gate drive and all necessary oscillator, control and protection circuitry. Unique error amp circuitry can regulate both positive and negative voltage...