DSP锁相放大器

美国斯坦福公司生产的SR830和SR810数字锁相放大器具有高性能，低价格等优势。SR830数字锁相放大器既显示幅值，有显示相位值。SR810锁相放大器只显示幅值。

使用数字处理技术（DSP）完全取代了传统的由解调器，滤波器和放大器组成的锁相放大器。

主要性能：

●频率范围1mHz 到102.4kHz

●＞100dB 的动态保留

●稳定性为5ppm/℃

●0.01 度的相位分辨率

●时间常数为10μs 到30ks（最大24dB倍频程衰减速率）

●具有自动获取，自动定相，自动存储

●自动补偿功能

●合成参考光源

●GPIB 和RS-232 两种接口

技术参数：

电压输入Single-ended or differential

分辨率 2 nV to 1 V

电流输入106 or 108 V/A

输入阻抗电压10 MΩ + 25 pF, AC or DC coupled

输入阻抗电流1 kΩ to virtual ground

增益精度±1 % (±0.2 % typ.)

噪声 (typ.) 6 nV/√Hz at 1 kHz; 0.13 pA/√Hz at 1 kHz (106 V/A); 0.013 pA/√Hz at 100 Hz (108 V/A)

线性滤波50/60 Hz and 100/120 Hz (Q = 4 )

CMRR100 dB to 10 kHz, decreasing by 6 dB/oct above 10 kHz

动态范围 >100 dB (without prefilters)

稳定性 <5 ppm/°C

参考通道：

频率范围0.001 Hz to 102.4 kHz

参考输入TTL or sine (400 mVpp min.)

输入阻抗1 MΩ, 25 pF

相位分辨率0.01° front panel, 0.008° through computer interface

相位误差<1°

相对相位误差<0.001°

正交性90° ± 0.001°

相位噪声Internal ref. Synthesized, <0.0001° rms at 1 kHzExternal ref. 0.005° rms at 1 kHz (100 ms time constant, 12 dB/oct)

相位漂移 <0.01°/°C below 10 kHz, <0.1°/°C above 10 kHz

谐波检测2F, 3F, ... nF to 102 kHz (n < 19,999)

收集时间(2 cycles + 5 ms) or 40 ms,whichever is larger

解调器：

稳定性   Digital outputs and display: no drift Analog outputs: <5 ppm/°C for all dynamic reserve settings

谐波YZ器?90 dB

时间常数 10 μs to 30 ks (6, 12, 18, 24 dB/oct rolloff). Synchronous filters available below 200 Hz.

内部振荡器：

范围   1 mHz to 102 kHz

频率精度25 ppm + 30 μHz

频率分辨率4? digits or 0.1 mHz, whichever is greater

失真?80 dBc (f <10 kHz), ?70 dBc(f >10 kHz) @ 1 Vrms amplitude

振幅    0.004 to 5 Vrms into 10 kΩ (2 mV resolution), 50 Ω output impedance, 50 mA maximum current into 50 Ω Amplitude accuracy 1 % Amplitude stability 50 ppm/°C Outputs Sine, TTL (When using an external reference, both outputs are phase locked to the external reference.)

显示：

通道1    4?-digit LED display with 40-segment LED bar graph. X, R, X-noise, Aux 1 or Aux 2. The display can also be any of these quantities divided by Aux 1 or Aux 2.

通道2    (SR830) 4?-digit LED display with 40-segment LED bar graph. Y, θ, Y-noise, Aux 3 or Aux 4. The display can also be any of these quantities divided by Aux 3 or Aux 4.

补偿    X, Y, R can be offset up to ±105 % of full scale.

放大倍率X, Y, R can be expanded by 10× or 100×.

参考    4?-digit LED display

输入和输出：

CH1输出     X, R, X-noise, Aux 1 or Aux 2,(±10 V), updated at 512 Hz

CH2输出    (SR830) Y, θ, Y-noise, Aux 3 or Aux 4,(±10 V), updated at 512 Hz

X, Y输出In-phase and quadrature components (rear panel) (±10 V), updated at 256 kHz.

Aux. A/D inputs4 BNC inputs, 16-bit, ±10 V,1 mV resolution, sampled at 512 Hz

Aux. D/A outputs 4 BNC outputs, 16-bit, ±10 V, 1 mV resolution

正弦    Internal oscillator analog output

TTL输出    Internal oscillator TTL output

数据缓冲器 The SR810 has an 8k point buffer. The SR830 has two 16k point buffers. Data is recorded at rates to 512 Hz and read through the computer interfaces.

触发输入 (TTL) Trigger synchronizes data recording

远程放大器 Provides power to the optional SR550, R552 and SR554 preamps

连接口 IEEE-488.2 and RS-232 interfaces standard. All instrument functions can be controlled and read through IEEE-488.2 or RS-232 interfaces.