Lock-In Amplifiers SR510 and SR530 — Lock-in amplifiers SR510 & SR530 Lock-In Amplifiers The SR510 and SR530 are analog lock-in amplifiers which can measure AC signals as small as nanovolts in the presence of much larger noise levels. Both the single phase SR510 and the dual phase SR530 have low-noise voltage and current inputs, high dynamic reserve, two stages of time constants, and an internal oscillator. In addition, both lock-ins come equipped with a variety of features designed to make them simple to use. · 0.5 Hz to 100 kHz frequency range · Current and voltage inputs · Up to 80 dB dynamic reserve · Tracking band-pass and line filters Sine Wave Mixing · Internal reference oscillator (opt.) The core of the SR510/SR530 is a precision analog sinewave multiplier. Lock-ins use a multiplier (demodulator) to translate the input signal (at the reference frequency) down to DC where it can be filtered and amplified. Many lock-ins use square wave multipliers which introduce spurious harmonic responses. The SR510/SR530 use clean sine-wave multipliers which are inherently free of unwanted harmonics. · Four ADC inputs, two DAC outputs · RS-232 interface (std.) · GPIB interface (opt.) Signal Input The SR510 and SR530 have differential inputs with 7 nV/√Hz of input noise and 100 MΩ input impedance. The input can be configured as a voltage input, or as a current input with 106 V/A gain and an input impedance of 1 kΩ to virtual ground. Full-scale sensitivities from 500 mV down to 100 nV are available. Three input prefilters can be selected. The first is a line notch filter providing 50 dB of rejection at the line frequency. The Stanford Research Systems

second filter similarly provides 50 dB of rejection at the second harmonic of the line frequency. The third filter is a band pass filter which automatically tracks the reference frequency. These three filters can eliminate much of the noise in the signal before it is amplified. Reference Input The reference input can be set to lock to sine waves or to either edge of a pulsed reference. The reference frequency range is 0.5 Hz to 100 kHz, and detection at both the fundamental and second harmonic of the reference is allowed. A convenient, built-in frequency meter constantly measures and displays...

Ordering Information SR510 Single phase lock-in amplifier (w/ rack mount) SR530 Dual phase lock-in amplifier (w/ rack mount) Option 01 GPIB interface for SR510/SR530 Option 02 Internal oscillator SR550 Voltage preamplifier (100 MΩ, 3.6 nV/√Hz) SR552 Voltage preamplifier (100 kΩ, 1.4 nV/√Hz) SR554 Transformer preamplifier (0.091 nV/√Hz) SR555 Current preamplifier SR556 Current preamplifier SR540 Optical chopper There are four A/Ds and two D/As on the rear panel that provide flexibility in interfacing the SR510/SR530 with external signals. These input/output ports measure and supply analog voltages...

Signal Channel Inputs Voltage Current Impedance Voltage Current Full-scale sensitivity Voltage Current Maximum inputs Voltage Current Noise Voltage Current Common Mode Range Rejection Gain accuracy Gain stability Signal filters Dynamic reserve Reference Channel Demodulator Stability 5 ppm/°C (LOW reserve) 50 ppm/°C (NORM reserve) 500 ppm/°C (HIGH reserve) Single-ended or differential 106 V/A 100 MΩ + 25 pF, AC coupled 1 kΩ to virtual ground 100 nV to 500 mV 100 fA to 0.5 µA 100 VDC, 10 VAC damage threshold, 2 Vpp saturation 10 µA damage threshold, 1 µApp saturation Time constants Pre Post Offset...