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5210 Dual Phase Analog Lock-in Amplifier

5210 Lock-in Amplifier
Model 5210

The 5210 has become the benchmark lock-in amplifier against which others are judged.  It is the most widely referenced in technical publications describing a diverse range of research applications including optical, electrochemical, electronic, mechanical and fundamental physical studies.
Since the introduction of the introduction of instruments using digital signal processing has brought advances in phase sensitive detection techniques, instruments using analog demodulators are still the first choice for many experiments. These include those requiring a true analog output, for example in some feedback control loops, or where the instrument is used to recover the envelope modulation of a carrier frequency.
Voltage or current inputs
The 5210 includes a current preamplifier with two transimpedance settings, so it can directly measure signals from current sources such as photodiodes. The instrument has an input impedance as low as 25 Ω (typically), the resulting voltage generated across the source by the signal current is minimized for the very best performance.

Continuous full-scale sensitivity control 
The 5210 offers a range of calibrated full-scale sensitivity settings. Unique to the 5210 is the sensitivity vernier control, allowing the full-scale sensitivity to be set to any value between the calibrated values. In performing an optical transmission experiment one can measure transmission in terms of a percentage relative to that of a “reference” sample.  The reference sample is placed in the optical path when the auto vernier control is activated.  

Unique Walsh Function Demodulators
The simplest method of implementing the phase sensitive detector at the heart of an analog lock-in is with a reversing switch driven at the reference frequency, giving excellent linearity, dynamic range and stability. This is known as a “squarewave” demodulator since the instrument responds to signals not only at the reference frequency but also at its odd harmonics. It offers much better performance than can be achieved by using a true analog multiplier, which requires the synthesis of a very pure reference sinusoid and is very nonlinear when handling large levels of interfering signal.
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    Item Model Number
    GPIB/USB Adapter CE0115S
  • Software +

    Item Model Number
    Acquire Software
    The software includes a powerful plotting engine that lets you show data just as you want it using a variety of line styles, allows data export to both text and CSV files, offers comprehensive clipboard support, and includes a context-sensitive help system
    Active X Control SRINSTCOMMS
  • Specifications +

    Dual-phase model 5210 analog lock-in amplifiers operating over a reference frequency range of 0.5 Hz to 120 kHz. Wide range of auxiliary inputs and outputs.

    Measurement Modes
    The model 5210 can simultaneously show one of these outputs on the front panel display:
    X In-phase
    R Magnitude
    0 Phase Angle
    Harmonic F or 2F
    Measures noise in a given bandwidth centered at the reference frequency F
    Two 3½-digit LCD displays and analog panel meter
    Signal Channel
    Voltage Input

    A only or Differential (A-B)
    Full-scale Sensitivity 100 nV to 3 V in a 1-3-10 sequence and vernier adjustment
    Max. Dynamic Reserve > 130 dB
    Impedance 100 MΩ // 25 pF
    Maximum Safe Input 30 V pk-pk
    Voltage Noise 5 nV/√Hz @ 1 khZ
    C.M.R.R. > 100 dB @ 1 kHz
    Frequency Response 0.001 hz to 120 kHz
    Gain Accuracy 1% typical in Flat mode, 2% typical in tracking Bandpass mode
    Gain Stability 200 ppm/ºC typical
    Distortion -90 dB THD (60 dB AC gain, 1 kHz)
    Grounding BNC shields can be grounded or floated via 1 kΩ to ground
    Current Input
    Mode 10-6A/V or 10-8 A/V
    Full-scale Sensitivity
    10-6 A/V

    100 fA to 3 µA in a 1-3-10 sequence and vernier adjustment
    1 -A to 300 µA in a 1-3-10 sequence and vernier adjustment
    Max. Dynamic Reserve > 130 dB
    10-6 A/V
    10-8 A/V

    < 250 Ω at 1 kHz
    <2.5 kΩ at 100 Hz
    Maximum Input 15 mA continuous, 1 A momentary
    10-6 A/V
    10-8 A/V

    130 fA/√Hz at 1 kHz
    13 fA/√Hz at 500 Hz
    Frequency Response
    10-6 A/V
    10-8 A/V

    -3 dB at 60 kHz
    -3 dB at 330 Hz
    Gain Accuracy 1% typical in Flat mode, 2% typical in tracking Bandpass mode
    Gain Stability 200 ppm/ºC typical
    Grounding BNC shield can be grounded or floated via 1 kΩ to ground
    Signal Channel Filters
    Line Frequency Rejection Filter
    Center frequency,
    F (factory set)

    50/100 or 60/120 Hz
    Off, F, 2F, F & 2F
    Main Signal Channel Filter

    Fourth-order Low-pass, Bandpass, Notch or Flat (Disabled)
    Auto or Manual turning
    Signal Monitor Front-panel BNC connector allows viewing of signal immediately ahead of the demodulators(s)
    Reference Channel
    TTL Input (rear panel)
    Frequency Range

    0.5 Hz to 120 kHz
    Analog input (front panel)
    Frequency Range
    Squarewave input
    Frequency Range

    *Note: Lower levels can be used with the analog input at the expense of increased phase errors

    1 mΩ // 30 pF
    1.0 V rms*
    0.5 Hz to 120 kHz

    250 mVrms*
    2 Hz to 120 kHz
    Phase Set Resolution 0.005º increments
    Phase Set Accuracy ± 1º
    Phase Noise 0.005º rms @ 1 kHz, 100 ms, 12 dB TC
    Phase Drift < 0.05º/ºC
    (model 5210 only)
    ± 0.5º above 5 Hz, degrading to ± 5º at 0.5 Hz
    Acquisition Time 100 ms + 2 cycles max
    Lock Indicator LED warns of frequency/phase unlock
    Demodulator and Output Processing
    Mode Sineware (Walsh demodulator + BP/LP filter) or Squarewave

    Zero stability /Dynamic Reserve

    Mode Dynamic Reserve
    Filter On
    Dynamic Reserve
    Filter Off
    Zero Stability
    High 130 dB 60 dB 500 ppm/ºC
    Normal 110 dB 40 dB 50 ppm/ºC
    High 90 dB 20 dB 5 ppm/ºC

    Harmonic Rejection > 80 dB with Low-pass, and > 60 dB with Bandpass main signal filter
    Output Filters
    Time Constant

    1 ms - 3 ks (1-3-10 sequence)
    6 dB/oct or 12 db/oct for all TC settings
    Offset Auto and Manual on X and/or Y: ±100% full-scale with Expand on)
    Frequency Range
    Amplitude Range
    Amplitude Resolution
    0 - 500 mV
    500 mV - 2 V

    0.5 Hz - 120 kHz
    0 - 2 V rms (front panel or computer); 5 V rms fixed (computer only)

    1 mV
    4 mV
    Distortion (THD) 0.5%
    Output sinewave from 900 Ω source
    Auxiliary Inputs
    ADC 1, 2, 3 and 4
    Maximum input
    Input Impedance
    Sample Rate
    Trigger Mode
    Trigger Input

    ±15 V
    1 mV
    ±20 mV
    1 MΩ // 30 pF
    100 Hz
    Internal, External or ref synchronous
    TTL compatible
    Demodulator Monitor 100 µs TC @ 6 dB/octave (5210: X output only)
    Main Analog (CH1 and CH2) Outputs
    5210: Two ±10 V FS (X, Y or R, 0)
    Resolution 1 mV
    Impedance 1 kΩ
    Update Rate 100 Hz
    Expand Expands X output by factor of 10
    Auxiliary D/A Outputs
    5210 One output, ±15 V
    Resolution 1 mV