LT1683

The LT^®1683 is a switching regulator controller designedto lower conducted and radiated electromagnetic interfer-ence (EMI). Ultralow noise and EMI are achieved bycontrolling the voltage and current slew rates of externalN-channel MOSFET switches. Current and voltage slewrates can be independently set to optimize harmoniccontent of the switching waveforms vs efficiency. TheLT1683 can reduce high frequency harmonic power by asmuch as 40dB with only minor losses in efficiency.

The LT1683 utilizes a dual output (push-pull) currentmode architecture optimized for low noise topologies. TheIC includes gate drivers and all necessary oscillator,control and protection circuitry. Unique error amp cir-cuitry can regulate both positive and negative voltages.

The oscillator may be synchronized to an external clock formore accurate placement of switching harmonics.Protection features include gate drive lockout for low V_IN,opposite gate lockout, soft-start, output current limit,short-circuit current limiting, gate drive overvoltage clampand input supply undervoltagelockout.