RFMW , Ltd. announces design and sales support for XSYSTOR controller modules used for operation and protection of depletion mode transistors. Primarily designed for GaN devices, controllers like the 200X02R0 protect GaN transistors during the power On/Off sequence of internal and external voltage supplies. The 200X02R0 is an inverting controller. A positive analog voltage from a potentiometer, ePOT, or microcontroller is inverted into a unity gain negative voltage for device gate bias. A single supply of 28-65VDC is all that is required. TTL enable for both gate and drain switching are independent or made sequential for stability purposes. The 200X02R0 drives CW and Pulsed drain switches with either open-drain or TTL format. One controller is capable of driving several switches or operating multiple transistors at less than 200nsec rise or fall times. Flexible mounting configurations include upright, slanted, or flat for orientation in very tight spaces.