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Products: High Voltage Function Generators

TREK Model 677B Power Amplifier/Supply

The Trek Model 677B is a high-voltage power amplifier/supply unit for precise control of output voltages in the range of 0 to ±2 kV DC or peak AC with an output current range of 0 to ±5 mA DC or peak AC. The Model 677B can be operated in one of two modes: as a high-voltage amplifier where it is configured as a noninverting amplifier with a fixed gain of 200 V/V, or as a high-voltage power supply which responds to front panel controls to command an exact output voltage or current. A differential input is available on the Model 677B-1.

The Model 677B features an all-solid-state design for high slew rate, wide bandwidth, and low-noise operation. The four-quadrant, active output stage sinks or sources current into reactive or resistive loads throughout the output voltage range. This is essential for achieving the accurate output response and high slew rates demanded by reactive loads.

The Model 677B is protected against over-voltage and over-current conditions that may be generated by active loads or by output short circuits to ground.

Precision voltage and current monitors provide low-voltage representations of the high-voltage output and load current for monitoring purposes, or for use as feedback signals in a closed-loop system.

The Digital Enable feature provides a connection for a remote device to turn on and off the high-voltage output. This makes the Model 677B suitable for automated or computer-controlled systems.

The Model 677B can be operated on a bench top or, with optional hardware, in a standard 19-inch rack.

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OUTPUT

  • Output Voltage Range Amplifier Mode
    0 to ±2 kV DC or peak AC.
  • Output Voltage Range Supply Mode
    Adjustable from 0 to +2 kV DC or 0 to -2 kV DC with 1 V resolution.
  • Output Current Range
    0 to ±5 mA DC or peak AC with an adjustable current limit.

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AMPLIFIER INPUT

  • Input Voltage Range
    0 to ±10 V DC or peak AC.
  • Input Impedance
    10 kiloohms, nominal.

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PERFORMANCE

  • General Performance
    • DC Accuracy
      Better than ±0.1% of full scale.
    • Offset Voltage
      Better than ±500 mV.
    • Output Noise
      Less than 100 mV rms (measured using the true rms feature of the Hewlett Packard Model 34401A digital multimeter).
    • Stability
      • Drift with Time
        Less than 100 ppm/hour, noncumulative.
      • Drift with Temperature
        Less than 350 ppm/°C.
    • Regulation
      • Line
        Better than 0.025% for a line change from 90 to 110 V AC, 103 to 127 V AC, or 207 to 250 V AC.
      • Load
        Better than 0.025% for a load change from 0 to 5 mA.
  • Amplifier Performance
    • DC Voltage Gain
      200 V/V.
    • Slew Rate (10% to 90%, typical)
      Greater than 15 V/µs.
      • Large Signal Bandwidth (1% distortion)
        DC to greater than 1.2 kHz.
    • Small Signal Bandwidth (-3dB)
      DC to greater than 5 kHz.
    • Settling Time to 1%
      Less than 300 µs for a 2 kV step.

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PRODUCT FEATURES

  • High Voltage On/Off
    A three-position switch to select on, off or remote. (See "Digital Enable" for information pertaining to remote on/off.)
  • Mode Switch
    Selects either the Amplifier or Supply mode of operation.
  • Supply Mode Voltage Control
    • Voltage Selection
      A multiturn control to set the desired output voltage as indicated by the digital display.
    • Polarity
      A two-position rocker switch.
  • Current Limit
    Adjustable from 1 mA to 5 mA. A multiturn control is used to set the current limit as indicated by the digital display. A yellow LED will illuminate when the instrument is in a current limit condition.
  • Current Limit Set Accuracy
    Better than 1% of setting.
  • Front Panel Display
    A 3-1/2-digit LED display can be selected to indicate the voltage output, the voltage setting (supply mode), the current output or the current limit setting. Two rocker switches are used to select the quantity displayed.
    • Range when Displaying Voltage
      0 to ±1999 V.
    • Range when Displaying Current
      0 to 5.00 mA.
    • Resolution when Displaying Voltage
      1 V.
    • Resolution when Displaying Current
      10 µA.
    • Zero Offset
      ±1 count, referred to the Voltage and Current Monitors.
  • Voltage Monitor
    A buffered output providing a low-voltage representation of the high-voltage output signal.
    • Scale
      1/200th of the high-voltage output signal.
    • DC Accuracy
      Better than 0.1% of full scale. (May degrade to 0.6% in the presence of RF fields up to 3 V/m.)
    • Offset Voltage
      Better than ±5 mV.
    • Output Noise
      Less than 10 mV rms (measured using the true rms feature of the Hewlett Packard Model 34401A digital multimeter).
    • Output Impedance
      Less than 0.1 ohms .
  • Current Monitor
    A buffered output providing a low-voltage representation of the load current.
    • Scale
      1 V/mA.
    • DC Accuracy
      Better than 1% of full scale.
    • Offset Voltage
      Better than ±5 mV.
    • Output Noise
      Less than 10 mV rms (measured using the true rms feature of the Hewlett Packard Model 34401A digital multimeter).
    • Bandwidth
      DC to greater than 800 Hz.
    • Output Impedance
      Less than 0.1 ohms.
  • Digital Enable
    An input for connection of a TTL compatible signal to turn on and off the high-voltage output when the High Voltage switch is in the Remote position. A TTL high (or open) will turn off the high-voltage output. A TTL low will turn on the high-voltage output.

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GENERAL

  • Power Requirements
    • Line Voltage
      Factory set for one of two ranges: 90 to 127 V AC or 180 to 250 V AC, at 48 to 63 Hz (specify when ordering).
  • Power Consumption
    60 VA, maximum.
  • Operating Conditions
    • Temperature
      0 °C to 40 °C.
    • Relative Humidity
      To 85%, noncondensing.
    • Altitude
      To 2000 meters.
  • Dimensions
    110 mm H x 220 mm W x 430 mm D
    (4.3" H x 8.7" W x 17" D).
  • Weight
    4 kg (9 lb).
  • High-Voltage Output Connector
    Alden high-voltage connector.
  • Amplifier Input
    BNC connector.
  • Voltage Monitor Connector
    BNC connector.
  • Current Monitor Connector
    BNC connector.
  • Digital Enable Connector
    BNC connector.
  • AC Line Cord Receptacle
    Standard IEC three-prong AC line connector.

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CERTIFICATION & COMPLIANCE

TREK, INC. certifies that each Model 677B is tested and calibrated to specifications using measurement equipment traceable to the National Institute of Standards and Technology or traceable to consensus standards. A Certificate of Calibration accompanies each instrument when it is shipped from the factory.

Low Voltage Safety Compliance (EN 61010-1)

Installation Category
CAT II: Local-level mains, appliances, portable equipment.

Pollution Category
Degree 1: Operate in environments where no pollution occurs or only dry, nonconductive pollution occurs.

All specifications are with no load unless otherwise noted and are subject to change.

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