THE PULSE OF THE FUTURE PVM-4210 DUAL OUTPUT HIGH VOLTAGE PULSE GENERATOR MODULE • • • • • • • • The PVM-4210 is a compact, OEM-style pulse generator module providing two simultaneous differential voltage pulses of up to ±950V (1,900V differential), with pulse rise and fall times <15 nanoseconds, and pulse widths continuously adjustable from <40 nanoseconds to DC. The pulser operates on +24VDC to +28VDC support power, and features integrated DC high voltage power supplies. The PVM-4210 is optimized for differential drive of deflection plates for electrostatic modulation of particle beams in time-offlight mass spectrometers and accelerators. It will also drive any high impedance, capacitive load such as Pockels Cells and QSwitches, electrodes, microchannel plates, acoustic transducers, image intensifiers and photomultiplier tubes. The exceptional pulse fidelity of the PVM-4210 will optimize the performance of any system in which it is used. The module provides two pulse output channels, controlled by a common control logic. When the control logic receives a gate signal, both channels pulse simultaneously. One channel pulses from ground to the positive high voltage, and the other channel pulses from ground to the negative high voltage. Therefore each output can be connected to the electrodes of a Pockels Cell or Q-Switch, or to a pair of deflection plates, providing a 1,900V differential pulse across the cell or plates. These outputs may also be inverted, to pulse from the high voltage potential to ground. The width and frequency of the output pulses follow the width and frequency of the TTL input gate. The amplitude of the output pulse voltage for each channel is independently adjustable from 0 to 950V using screwdriver-adjustable potentiometers readily accessible on the end panel of the pulser module. The PVM-4210 requires +24VDC to +28VDC support power and a TTL gate signal. For safety and control flexibility, a TTL level signal is used to enable and disable the DC power supplies. Simultaneous Positive And Negative 0 To +950V and 0 To –950V Pulse Outputs 1,900V Differential Output <15ns Rise And Fall Times <40ns to DC Pulse Width >20KHz Pulse Repetition Frequency Internal High Voltage Power Supplies Optimized To Drive Deflection Plates, Pockels Cells, Q-Switches And Other Capacitive Loads Economical, Modular Solid State Design Each channel is a half-bridge (totem pole) design, offering equally fast pulse rise and fall times, low power dissipation, and virtually no over-shoot, under-shoot or ringing. The unit has over-current detection and shut-down circuitry to protect the pulse generator against potential damage due to arcs and shorts in the load or interconnect cables. Unlike some competing solid state switches, the PVM-4210 is a complete pulser solution with high voltage power supplies, energy storage and output network, ready for use. It can be connected directly to the load, and does not require series or shunt resistors, impedancematching networks between the pulser and the load, or additional energy storage (capacitor banks). All of this is taken care of within the PVM-4210. The pulser is housed in an aluminum enclosure, with threaded mounting holes in the base to simplify installation and assembly in OEM applications. The PVM-4210 is a direct-coupled, all solid-state design using air as the primary insulating medium. Its conservative design margin gives you long component life. And keeping the PVM-4210 free of potting compound or encapsulation materials makes it easy to service if a component ever does require replacement. Some competing products are potted, and must be replaced if they fail. But compactness and durability are not all you get in the PVM4210. Inherent in the design is exceptional pulse fidelity with virtually no ringing, over-shoot or under-shoot, and protection against arcs, shorts and load transients in a reliable, economical module. DIRECTED ENERGY INCORPORATED THE PULSE OF THE FUTURE SPECIFICATIONS (All specifications measured into a 50pF load connected to each of the two outputs with 12” (~30cm) of Belden 8218 75Ω coaxial cable ) OUTPUT PULSE ELECTRICAL CHARACTERISTICS (Specifications Apply To Both Output Channels) Output Voltage Output Voltage Adjustments Pulse Width Pulse Rise And Fall Time Pulse Recurrence Frequency 0 to +950V ±5V (Channel 1), 0 to –950V ±5V (Channel 2) Screwdriver-adjustable potentiometers, End Panel <40ns to DC measured FWHM, controlled by input gate ≤15ns, 10%-90% Pulse Droop Single Shot to >20KHz continuous, 5MHz burst, controlled by input gate (1) <1% Over/Undershoot <5% Jitter <1ns Shot-to-Shot Throughput Delay (Delay from leading edge of input gate to leading edge of output pulse) Maximum Duty Cycle 93ns typical Maximum Average Power (Per Channel) 4W (1) Pulse Output Connectors SHV, End Panel Output Cables 12” (~30cm) Belden 8218 75Ω Coaxial Cable Min. Pulse Width: 38ns at 950V 10ns/Div horizontal scale, 200V/Div vertical scale Continuous GATE Typical Differential Output, ±950V Gate Source External Gate Input TTL into 50Ω Gate Rise Time <20ns Gate Connector DSUB, End Panel 2.5µs/Div horizontal scale, 318V/Div vertical scale, center horizontal trace is ground GENERAL Support Power 24VDC to 28VDC @ 600mA Maximum Current Dimensions (Excluding Connectors) 5.5”W x 11”L x 1.75”H (140mm W x 279.5mm L x 44.5mm H ) 41 Ounces (1.16 kilograms) Weight (Approximate) Pulse Fall Time: 13ns at 950V Specifications subject to change without notice 10ns/Div horizontal scale, 200V/Div vertical scale (1) The power dissipated in each channel of the PVM-4210 when driving a capacitive load is defined by the formula CV2F, where C is the total load capacitance, including the capacitance of the load, interconnect cable, and the internal capacitance of the PVM-4210, V is the pulse voltage, and F is the pulse repetition frequency (or the total pulses per second). (For these calculations, the internal capacitance of the PVM-4210 is 125pF, and Belden 8218 cable is 21.5pf/foot.) Given the maximum power supply capability of 4W (4mA) per channel, the maximum load capacitance, frequency and/ or voltage at which the PVM-4210 can operate can be approximated using this formula. At lower load capacitances and/or voltages less then 950V, the PVM-4210 can operate at continuous pulse recurrence frequencies greater than 20KHz. This formula is not applicable when driving non-capacitive (resistive or inductive) loads. Contact DEI for information or assistance in using the PVM-4210 with different load characteristics or impedances. 5MHz Pulse Burst, 950V Output 20KHz Frequency, Both Channels 250ns/Div horizontal scale, 200V/Div vertical scale 25µs/Div horizontal scale, 318V/Div vertical scale 9200-0204 Rev 3 © Directed Energy, Inc. 2000 Directed Energy, Inc. An IXYS Company 2401 Research Blvd., Suite 108 Fort Collins, CO USA 80526 970-493- 1901 Fax: 970-493-1903 Email: [email protected] Web: http://www.directedenergy.com