Model 1487 CRT High Voltage Power Supply

• Triple output CRT power supply (anode, focus and grid)
• All outputs adjustable
• Low line and load regulation of high voltage outputs
• All outputs short circuit and arc protected
• Remotely programmed shutdown for each output
• Each output is current limited
• Compact size - 6 x 4 x 4 in.
• DB-9 I/O connector

Model 1210 is a high-stability power supply designed for the difficult requirements of electron microprobes and focused ion beam systems. It features low ripple and low stored energy. The low stored energy at the output reduces computer system upsets when arcing occurs within the beam column and prevents damage to the semiconductor wafer being probed. Outputs are available to 30 kV. The standard output voltage is 20 kV.

The low output ripple is the result of using sine wave excitation to the high voltage multiplier plus the use of a novel ripple cancellation circuit. Hence, low output ripple is achieved without using a large value output capacitor. Sine wave excitation generates less noise on the input power line compared to square wave excitation.

The 1210 uses separate power return lines for the high voltage load, the input power and the voltage programming reference. Separating these signals reduces unwanted interactions between the critical programming reference and the other circuits.