THE PULSE OF THE FUTURE PVX-4150 ± 1 , 5 0 0 V P U L S E G E N E R AT O R • • • • • • • The PVX-4150 pulse generator produces fast, high voltage wave forms to 1,500V. Optimized for high impedance capacitive loads, the PVX-4150 is well suited for driving extraction grids and deflection plates for electrostatic modulation of particle beams in time-of-flight mass spectrometers and accelerators. Its robust and versatile design also makes it well suited for pulsing or gating power tube grids, Pockels cells and Q Switches, acoustic transducers, microchannel plates, photomultiplier tubes and image intensifiers. The exceptional pulse fidelity of the PVX-4150 will optimize the performance of any system in which it is used. The PVX-4150 generates an output voltage pulse of 1,500 volts with rise and fall times less than 25ns, with very flat voltage pulses to DC into a capacitive load. It can generate singled-ended output pulses from ground to +1500V or from ground to –1500V, and can also generate pulses originating from a DC voltage offset from ground by using both VLow and VHigh power supply inputs. This offset can be from –1500V to +1500V, with a maximum power supply voltage differential of ≤1500V. The PVX-4150 requires a TTL gate signal, a high voltage DC power supply and optional DC offset supply inputs. The output pulse width and frequency are controlled by the gate signal. The pulse output voltage is controlled by the amplitude of the input DC power supplies. 0 to ±1500V Pulse Output <25ns Rise And Fall Times <60ns to DC Pulse Width >240KHz Pulse Repetition Frequency Optimized To Drive Deflection Plates, Grids And Other Capacitive Loads Protected Against Arcs, Shorts And Load Transients Voltage And Current Monitor Outputs be used to generate a negative-going pulse by logically inverting the input gate, so that the input gate is high until the unit is pulsed. When the input gate goes low, the VLOW input supply is connected to the output, thereby generating a negative-going pulse. The PVX-4150 features front panel indicator LEDs to monitor the status of the pulse generator. Front panel voltage and current monitors provide a straightforward means to view the output voltage and current waveforms in real-time, eliminating the need for an external high voltage oscilloscope probe. The pulse generator is a direct-coupled, air-cooled solidstate 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. It has over-current detection and shut-down circuitry to protect the pulse generator from potential damage due to arcs and shorts in the load or interconnect cable. All control and protection logic circuitry, support power, energy storage and output network are incorporated into the PVX-4150. It can be connected directly to the load, and does not require series or shunt resistors, impedance-matching networks between the pulser and the load, or additional energy storage (capacitor banks). All of this is taken care of within the PVX-4150. When the input gate is high, the VHIGH supply is connected to the output. When the input gate is low, the VLOW supply is connected to the output. Therefore the PVX-4150 can DIRECTED ENERGY INCORPORATED THE PULSE OF THE FUTURE SPECIFICATIONS (All specifications measured into a 50pF load connected with 6 feet (~1.8M) of RG-62 (93Ω) coaxial cable) OUTPUT Maximum Value: Minimum Value: Means Of Adjustment: Pulse Rise And Fall Time: Pulse Width: Pulse Recurrence Frequency (PRF): Max. Average Power: Max. Duty Cycle: Droop: Over/undershoot: Throughput Delay Jitter: Output Connector & Cable: ±1500 Volts (VHigh - VLow) 0 Volts Controlled By Power Supply Input Voltages <25ns, typically <20ns (10% to 90%) <60ns to DC, Controlled by Input Gate Single shot to 240KHz at 1500V continuous output, maximum limited by power dissipation (1), 5MHz Burst, Controlled by Input Gate 150W (VHigh + VLow), derated at 2W/°C over 25°C ambient (1) Continuous <1% <5% 120ns Typical <1ns shot-to-shot <60ns Minimum Pulse Width, 1500V Output (25ns/Div horizontal scale, 300V/Div vertical scale) SHV, With 6 feet (~1.8M) RG-62 (93Ω) Coaxial Cable INPUT DC VOLTAGE +VIN (VHigh) Absolute Max. Value: +1500 Volts Absolute Min. Value: -1500 Volts Relative Max. Value: +1500 Volts over VLow Voltage Relative Min. Value: +0V Over VLow Voltage 18ns Rise & Fall Times, 1500V Output (10ns/Div horizontal scale, 300V/Div vertical scale) INPUT DC VOLTAGE -VIN (VLow) Absolute Max. Value: +1500 Volts Absolute Min. Value: -1500 Volts Input DC Connectors: SHV, Rear Panel (One each for +VIN and -VIN) GATE Gate Source & Connector TTL into 50Ω, into BNC connector on the front panel VOLTAGE & CURRENT MONITORS Voltage Monitor: 1000:1 into 1 MegΩ, BNC connector Current Monitor: 10A/V into 50Ω, BNC connector GENERAL Support Power: Dimensions (Excluding Connectors): Weight (Approximate): Typical Output Waveform, 1500V (1µs/Div horizontal scale, 300V/Div vertical scale) 90VAC to 240VAC, 50/60Hz 19” W x 5.2” H x 13” D (48.25cm W x 13.2cm H x 33cm D) 18 lbs. (8.2 Kilograms) SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE These specifications are measured driving a 50pF load connected with 6 feet of RG-62 cable, at 1500V output. However the PVX-4150 can drive loads of a few picofarads to several hundred picofarads of capacitance, limited by its maximum power dissipation capability(1) . At lower load capacitances and/or voltages less then 1500V, the PVX-4150 can operate at continuous pulse recurrence frequencies above 240KHz. The PVX-4150 can also drive resistive or inductive loads, within limitations. Contact DEI for additional information and applications assistance. (1) The power dissipated in the PVX-4150 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 PVX-4150, 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 PVX-4150 is 200pF, and RG-62 cable is 13pf/foot.) Given the maximum dissipation of 150W, the maximum load capacitance, frequency and/or voltage at which the PVX-4150 can operate can be approximated using this formula. This formula also approximates the high voltage power supply requirements needed to drive a given load at a specific voltage and frequency. This formula is not applicable when driving resistive or inductive loads. 244KHz Frequency, 1500V Output (2.5µs/Div horizontal scale, 300V/Div vertical scale) Doc #9200-0209 Rev 2 © Directed Energy, Inc. 2000 Directed Energy, Inc. 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