The LT1683 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 external N-channel MOSFET switches. Current and voltage slew rates can be independently set to optimize harmonic content of the switching waveforms vs efficiency. The LT1683 can reduce high frequency harmonic power by as much as 40dB with only minor losses in efficiency. The LT1683 utilises a dual output (push-pull) current mode architecture optimized for low noise topologies. The IC includes gate drivers and all necessary oscillator, control and protection circuitry. Unique error amp circuitry can regulate both positive and negative voltages. The oscillator may be synchronized to an external clock for more accurate placement of switching harmonics. Protection features include gate drive lockout for low VIN, opposite gate lockout, soft-start, output current limit, short-circuit current limiting, gate drive overvoltage clamp and input supply undervoltage lockout.
