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Products: High Voltage Amplifiers

Model 623B High-Voltage Power Amplifier

The Trek Model 623B DC-stable high-voltage power amplifier is designed to provide precise control of bi-polar output voltages in the range of 0 to ±2 kV DC or peak AC with an output current capability of ±40 mA DC or peak AC. Applications for the Model 623B include electrostatic beam deflection, electrooptic modulation, electrophoresis research, and piezoelectric poling and driving.

Features of the Model 623B power amplifier include an all-solid-state design, a slew rate greater than 300 V/µs, a large signal bandwidth of DC to greater than 10 kHz, and low noise operation. The four-quadrant active output sta ge sinks or sources current into reactive or resistive loads throughout the output voltage range which is essential for achieving the accurate output responses and high slew rates demanded by reactive loads.

The Model 623B features a current trip or current limit that is adjustable from 2 to 40 mA using the Current Trip/Limit Adjust potentiometer on the front panel. When the Model 623B enters a current trip condition, the high-voltage power amplifier output is disabled, the Trip Status indicator will illuminate and the Trip Monitor output will provide a TTL low. When the current limit operation is selected, the output crosses over to a constant current supply at the programmed limit value. The Model 623B 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 output signals for monitoring purposes or for use as feedback signals in closed-loop control systems. A Digital Enable feature provides a connection for a remote device to turn the high voltage on and off.

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PERFORMANCE

  • DC Voltage Gain
    • Noninverting Configuration
      1000 V/V.
    • Inverting Configuration
      -1000 V/V
    • Differential Configuration
      Function of the difference between two input signals. Represented by the equation:
      V out = V in(A) x (1000 V/V) + V in(B) x (-1000 V/V)
  • DC Voltage Gain Accuracy
    Better than 0.1% of full scale.
  • Offset Voltage
    Less than ±1 V.
  • Output Noise
    Less than 80 mV rms (measured using the true rms feature of the Hewlett Packard Model 34401A digital multimeter).
  • Slew Rate (10% to 90%, typical)
    Greater than 300 V/µs.
  • Large Signal Bandwidth (1% distortion)
    DC to greater than 10 kHz.
  • Small Signal Bandwidth (-3dB)
    DC to greater than 40 kHz.
  • Settling Time (to 1%)
    Less than 150 µs for a 2 kV step.
  • Stability
    • Drift with Time
      Less than 100 ppm/hr, noncumulative.
    • Drift with Temperature
      Less than 200 ppm/°C.
  • Automatic Power Limit
    Automatically limits the output power to protect the Model 623B from overheating due to excessive internal power dissipation. The following graph illustrates the Model 623B operating range automatic power limits.

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PRODUCT FEATURES

  • Amplifier Input
    Three pin input connector that can be configured for inverting, noninverting, or differential amplification.
  • Digital Enable
    An input providing a connection for a TTL compatible signal to turn on and off the high-voltage output. A TTL high (or open) turns off the high-voltage output. A TTL low turns on the high-voltage output.
  • Response Adjust
    A graduated one-turn potentiometer used to optimize the AC response of the Model 623B.
  • Trip/Limit
    Switch selectable for either Current Trip mode or Current Limit mode. A graduated one-turn potentiometer is used to adjust the current trip/limit value from 2 to 40 mA.
  • Out Of Regulation Indicator
    An amber indicator will illuminate when the Model 623B fails to produce the required high-voltage output such as during a current limit.
  • Trip Status
    An amber indicator will illuminate and the Trip Monitor BNC connector will provide a TTL low when the high-voltage output is disabled due to the output current exceeding the current trip level.
  • Voltage Monitor
    A buffered output providing a low-voltage replica of the high voltage output.
    • Scale
      1/1000th of the high-voltage output signal.
    • DC Accuracy
      Better than 0.1% of full scale.
    • Offset Voltage
      Less than ±2.5 mV.
    • Output Noise
      Less than 2 mV rms (measured using the true rms feature of the Hewlett Packard Model 34401A digital multimeter).
    • Output Impedance
      0.1 ohm.
  • Current Monitor
    A buffered output providing a low-voltage representation of the load current.
    • Scale
      0.25 V/mA.
    • DC Accuracy
      Better than 0.5% of full scale.
    • Offset Voltage
      Less 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 (-3db)
      DC to greater than 10 kHz.
    • Output Impedance
      47 ohms.

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OUTPUT

  • Output Voltage Range
    0 to ±2 kV DC or peak AC.
  • Output Current Range
    0 to ±40 mA DC or peak AC.
    (See Automatic Power Limit feature for limitations.)

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AMPLIFIER INPUT

  • Input Voltage Range
    0 to ±2 V DC or peak AC.
  • Input Impedance
    • Noninverting
      25 kohm, nominal.
    • Inverting
      50 kohm, nominal.
    • Differential
      50 kohm, nominal.

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ACCESSORIES

  • Accessories Supplied
    • Operator’s manual, Amphenol 3-pin mating connector with 3 meters of cable, Alden 3 meters (10 ft) high-voltage output cable assembly, and line cord.

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GENERAL

  • Dimensions
    134 mm H x 432 mm W x 439 mm D
    (5.25" H x 17" W x 17.25" D).
    • Weight
      13.2 kg (29 lb).
  • High-Voltage Output Connector
    Alden high-voltage connector.
  • Amplifier Input
    Amphenol panel mount.
  • Voltage Monitor Connector
    BNC connector.
  • Current Monitor Connector
    BNC connector.
  • Digital Enable Connector
    BNC connector.
  • Trip/Limit Connector
    BNC connector.
  • AC Line Receptacle
    Standard IEC three-prong AC line connector with integral fuse holder.
  • 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
      220 VA, maximum.
  • Operating Conditions
    • Temperature
      0 °C to 40 °C.
    • Relative Humidity
      To 85%, noncondensing.

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CERTIFICATION

TREK, INC. certifies that each Model Model 623B 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
    • Installation Category
      CAT II: Local level mains, appliances, portable equipment.
    • Pollution Category
      Degree 1: Operate in environments where no pollution or only dry, nonconductive pollution occurs.
    All specifications are with no load unless otherwise noted and are subject to change.

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