Applied Kilovolts Ltd.
Woods Way
Goring By Sea
West Sussex
BN12 4QY
U.K.
Tel: +44 (0) 1903 708850
Fax: +44 (0) 1903 708851
sales@appliedkilovolts.com

Digital Control System for High Precision Power Supplies Applications : Precise HV control for - Mass spectrometers - Electron microscopes - Electron Guns - Ion Guns - Surface Science - X-Ray Systems • High Stability - Very low temp co <5ppm/ °C • 16 bit monotonic DAC for Voltage Control • Very low noise injection, very high noise immunity • Optically Isolated Data Path • Ground loop offsets & noise eliminated • 12 Bit Readback of o/p Current, 8 BitReadback of o/p Voltage • Ribbon Cable interwiring - easy configuration & reconfiguration • Safe Operation • Single USB port for up to 64 PSUs • Fibre Optic bridge for Ion/Electron gun applications

This Digital Interface system uses a proprietary bus structure to provide a very low noise, highly stable control for up to 64 of our Precision High Voltage power supply modules, both unipolar, and reversible, via a single USB port. A simple ribbon cable connection scheme to a master interface and a 24V power supply enables a safe, flexible, multichannel high voltage system to be quickly and easily configured, and reconfigured, for such applications as Mass Spectrometers, Electron Microscopes, & Surface Science Equipment A fibre-optic data path is also available for high voltage isolation, for Electron Gun and Ion Gun applications, where control of a group of power supplies elevated to many kV is easily configured. Safety is paramount: power is removed from a module, the moment its comms path is broken. The Digital Control Interface PCB fits directly on the Molex i/p connector of the HP series High Voltage power supply, and is contained within the envelope of the PSU, or inside the case of the LS Precision High Voltage Modules. A 15Way ribbon cable from the USB receiver and 24V power supply, provides both the power and digital control signals, and can be readily daisy-chained, for ease of inter-wiring. A fibre optic bridge is also available to connect to a group of supplies not at ground potential. The fibre optic relay module receives the fibre-optic coms and relays them on to another similar module if required – as illustrated. This make is very easy to control and monitor multiple electron guns and ion guns.

FEATURES :
Proprietary bus structure for minimal noise injection to the analogue control signals.
Analogue compensation for power supply cabling voltage drops.
Up to 64 Precision supplies can be controlled by one USB PC port.

SAFETY :
Digital On/Off control of supply to each PSU, provides removal of the ‘source of energy’.
In the default mode, if the USB connection powers down, or is unplugged, then the high voltage enable bus control line goes low and the high voltage supplies are turned off. This can be disabled by a link in the USB receiver, so that the modules remain at their set levels.
If HV enable is forced low externally by an open collector transistor, then the high voltage supplies are turned off.
The optical link sends idle packets so if these packets are not seen for 2 frames, then the high voltage enable is turned off, and all isolated supplies will be turned off, but this too can be over-ridden with a link.

SOFTWARE :
A Template is provided to save re-generating the USB source code, for ease of system integration. The source code, in Visual Basic can be provided if necessary.