The UC2856 is a high performance version of the popular UC2846 series of current mode controllers, and is intended for both design upgrades and new applications where speed and accuracy are important. All input to output delays have been minimized, and the current sense output is slew rate limited to reduce noise sensitivity. Fast 1.5-A peak output stages have been added to allow rapid switching of power FETs. A low impedance TTL compatible sync output has been implemented with a 3-state function when used as a sync input.