Avalanche Transistor Pulser for Fast-Gated Operation of Micro-Channel Plate Image-Intensifiers

摘要

Transistors operated in the avalanche mode are employed to generate a 1000 volt 10 to 30 nsec wide pulse with less than 4 nsec rise and fall times. This pulse is resistively attenuated to approximately equal to 270 volts and drives the image intensifier tube which is a load of approximately equal to 200 pf. To reduce stray inductance and capacitance, transistor chips were assembled on a thick-film hybrid substrate. Circuit parameters, operating conditions, and coupling to the microchannel plate image-intensifier (MCPI exp 2 ) tube are described. To provide dc operating voltages and control of transient voltages on the MCPI exp 2 tube a resistance-capacitance network has been developed which (a) places the MCPI exp 2 output phosphor at ground, (b) provides programmable gains in ''f-stop'' steps, and (c) minimizes voltage transients on the MCPI exp 2 tube. (ERA citation 03:024987)