Stanford Research Systems SR865A, Руководство по эксплуатации

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Specifications vii
SR865A DSP Lock-in Amplifier
SR865A Specifications
Signal Channel
Voltage Inputs Single-ended (A) or differential (A−B)
Sensitivity (Output Scale) 1 nV to 1 V (voltage input)
1 fA to 1 μA (current input)
Input Impedance 10 M Ω +25 pF, ac (>1 Hz) or dc coupled
Input Range 10 mV to 1 V (peak); max input before overload
Gain Accuracy 1% below 200 kHz and 2% to 4 MHz (signal amplitude <30% of input range)
Input Noise 2.5 nV/√Hz above 1 kHz, 10 mV input range (typical)
CMRR Greater than 90 dB at 1 kHz (dc Coupled)
Harmonic Distortion −80 dB below 100 kHz, −60 dB above 100 kHz
Dynamic Reserve Greater than 120 dB
Current Input Ranges 1
μ
A or 10 nA
Reference Channel
Frequency Range 1 mHz to 4 MHz
Timebase 10 MHz In/Out phase locks the internal frequency to other SR865A units
Ext TTL Reference Minimum 2 V logic level, rising or falling edge
Ext Sine Reference 400 mV pk–pk minimum signal, ac coupled (>1 Hz)
Ext Reference Input Impedance 1 M Ω or 50 Ω
Acquisition Time (2 5 ms) or 40 ms, whichever is greater
Phase Setting Resolution 360/2 32 deg
Phase Noise Ext TTL reference: <0.001° rms at 1 kHz, (100 ms, 12 dB/oct) (typical)
Internal reference: <0.0001° rms at 1 kHz (100 ms, 12 dB/oct)
Phase Drift Sine Out to Signal In (200 mVrms)
<0.002°/°C below 20 kHz (dc coupled input)
<0.02°/°C below 200 kHz
<0.2°/°C below 2 MHz
Harmonic Detect Detect at N×f
ref
where N≤99 and N×f
ref
<4 MHz
Dual F Reference Detect at f
dual
= | f
int
− f
ext
|
All frequencies less than 4 MHz for specified performance
Chopper Reference SR865A drives SR540 Chopper (via Aux Out 4) to lock the chopper to f
int
Demodulator
dc Stability Digital output values have no offset drift
Time Constants 1 μs to 30 ks
Low Pass Filters Typical RC type filters or Advanced Gaussian/Linear Phase filters
Filter Slope 6, 12, 18, 24 dB/oct rolloffs
Synchronous Filter Available below 4 kHz
Harmonic Rejection −80 dB
Low Latency Output Rear panel BlazeX output with <2 μs delay (plus low pass filter rise/fall times)
Internal Oscillator
Frequency 1 mHz to 4 MHz
Frequency Accuracy 25 ppm + 30 μHz with internal timebase
External Timebase 10 MHz timebase input/output on rear panel
Frequency Resolution 6 digits or 0.1 mHz, whichever is greater