LI5640 (1mHz to 100kHz, 2nV Full-scale Multifunction Digital Lock-in Amplifier (Multifunction Type) with Phase Stability 0.01°/°C, Gain Stability ±100ppm/°C, Time Constant (at Minimum) 10µs and Built-in Oscillator)

Brand: NF
Model Series: LI5600 Series

About Product

Lock-in Amplifier is used for detecting and measuring AC signal’s amplitude or phase buried in noise as high sensitive AC Voltmeter with noise immunity. For the DSP lock-in amplifier, NF has taken full advantage of the sophisticated computation capacities of digital signal processors, while significantly improving the speed for setting and response during measurement, the stability of output and the compatibility of data with computers, at the same time as pursuing operability and lower cost. NF has full confidence in its experience and know-how in lock-in amplifiers. The NF LI5600 Series Digital Lock-in Amplifiers are thus designed and used by many customers like in the fields of physics and science including spectroscopic analysis.

Product Features

  • Line-up of two products
    • There are two models available for the product, namely the multi-functional and fully equipped digital lock-in amplifier LI 5640 and the economic digital lock-in amplifier LI 5630 with the same basic performance but of simpler functional line-up. Both models are of two-phase type
  • High stability
    • The amplifier features high stability and low drift designs in which all processes have been digitized except for the preamplifier used for input. Zero output drift was reduced to miniscule levels in the high sensitivity regions. Phase stability is 0.01°/°C and gain stability is ±100 ppm/°C. This high stability has formed the backbone for high resolution of 4½ digits and the phase noise of 0.001°. These features enable very reliable small signal measurements
    • Voltage input
      • Basic gain accuracy: ±0.5%
      • Basic gain stability: ±100ppm/°C
    • Current input (LI5640)
      • Basic current accuracy: ±1%
      • Basic gain stability: ±150ppm/°C
    • Phase sensitive detector
      • Basic phase stability: 01°/°C
    • Internal Oscillator
      • Frequency range: 5mHz to 105 kHz
      • Basic accuracy: ±30ppm
  • Prompt and smooth responses
    • Prompt and smooth measurement responses
      • The minimum time constant for the wave detection part is 10µs. D/A conversion of direct current output is possible with high speed and accuracy, at up to 256k samples/sec and 16 bit. Responses are prompt not only for X-Y but also for R-θ output. Up to 16k samples/second is possible for recording with digital data memory. Moreover, the amplifier features the new synchronized filter, allowing a moving average to be maintained with signal period. Ripples in measurement are significantly reduced, even with small time constants. In addition, the synchronized filter can be used in all frequency ranges. We invite everyone to enjoy fully the prompt and smooth responses
    • Instantaneous responses when settings are switched
      • Even when the settings for phase and sensitivity are changed during a measurement, the latest value is converted to the value for the new setting, allowing instantaneous responses for measurement. Even when the time constant is large, you do not need to wait for the time constant response
  • Equipped with analog meter to help an user grasp the measurement intuitively
    • LI5630: 1 analog meter
    • LI5640: 2 analog meters
  • Built-in oscillator (LI5640)
  • Versatile interfaces: GPIB and RS232 are provided as standard

Product Functions

  • Measurement is possible starting from 1mHz
    • Measurement is possible from 1mHz, something that could never be achieved with analogue lock-in amplifiers. A new way has been paved for low-speed phenomenon analysis, such as infrared spectroscopy and temperature response. Digital systems naturally allow high stability. You need never worry about drift in measurements. It is also to the advantage of low frequency measurements that signals are locked to the reference signal in approximately two periods
  • Easy operation
    • The amplifier features a one-way set up for signal input, filter, dynamic reserve, sensitivity and time constants, in that order from left to right. Because it is easy to see the key arrangement, errors in settings are prevented. The auto-set button is convenient for setting unknown input signals. There are three sets of large displays. They ensure accurate reading of settings and measurements. In addition, modify dial and analogue meters are also provided. You can enjoy the capabilities of the digital lock-in amplifier in an analogue style
  • Measurement display
    • LI5630
      • DATA parameter: X, Y, R , θ
    • LI5640
      • DATA1 parameter: X (= R cosθ), R, NOISE, AUX IN 1
      • DATA2 parameter: Y (= R sinθ), θ, AUX IN 1, AUX IN 2
  • Auxiliary input (DC voltage measurement)
    • LI5630: 1 channel
    • LI5640: 2 channels
  • Auxiliary output (DC voltage output): 2 channels (LI5640)
  • Automatic setting function is available
  • Data memory
    • LI5630
      • [DATA], [AUX IN], [X, Y] ,[R, θ], [DATA, AUX IN], [X, Y, reference signal frequency], [R, θ, reference signal frequency], [X, Y, AUX IN, R], [R, θ, AUX IN, X]
  • LI5640
    • [DATA1], [DATA2], [DATA1, DATA2], [DATA2, AUX IN2], [DATA1, DATA2, reference signal frequency], [DATA1, DATA2, AUX IN1, AUX IN2]

Product Application

  • Detecting and measuring AC signal’s amplitude or phase buried in noise
  • Spectroscopic reflective measurement of materials (See photo section)
  • Measurement of thermal conductivity properties of materials (See photo section)
  • Optical measurement for intensity and absorption
    • Spectroscopy analysis for general spectroscopy, auger electron spectroscopy, photo-acoustic spectroscopy and Raman spectroscopy
  • Photo gyro
  • Magnetic measurement (Evaluation of magnetic materials, vibration type magnetometer, magnetic detection using SQUID)
  • Sensor evaluation
  • Bridge detector
  • Impedance measurement
  • Mechanical vibration measurement
  • Biological/physiological signal measurement

Standard Accessories

  1. GPIB Interface
  2. RS232 Interface
  3. 3-pole/2-pole Converting Adapter
  4. Protective Cap (For Current Input Connector)
  5. Fuse
  6. Operation Manual
  7. Power Cable

Product Options

  • None

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