Stanford Research Systems Generators
5 models with full specifications in Generators.
Stanford Research Systems (SRS) designs high-precision signal, function, and digital delay generators for scientific research and engineering laboratories. Their instrumentation portfolio addresses distinct testing domains: high-resolution delay and pulse generation, standard direct digital synthesis (DDS) function generation with arbitrary capability, and ultra-low distortion audio-frequency testing. By focusing on low noise, high frequency resolution, and excellent amplitude accuracy, SRS instruments provide reliable reference signals for laser timing, component characterization, acoustic testing, and general-purpose laboratory calibration. This guide highlights the key technical differences across the SRS generator range to assist engineers in selecting the correct instrument for their specific performance requirements.
- DDS Frequency Range
- 1 µHz up to 30.2 MHz
- Delay Resolution
- 5 ps (DG535)
- Ultra-Low THD (DS360)
- -110 dB typ. (< 5 kHz)
- Delay Channels
- 4 independent channels
All models
| Model | Type | Amplitude Resolution | Dimensions (W×H×D) | Operating Temperature |
|---|---|---|---|---|
| DG535 | Pulse | 10 mV | 356 × 89 × 356 | 0 to +50 |
| DS345 | Arbitrary | 3 digits | 216 × 89 × 330 | 0 to 50 |
| DS360 | Function | 3 digits | 432 × 89 × 413 mm (17" × 3.5" × 16.25") | 0 °C to 50 °C |
| DS335 | Function | 3 digits | 216 mm × 89 mm × 330 mm | 0°C to 50°C |
| DS340 | Function | 3 digits | 216 mm × 89 mm × 330 mm | 0 °C to 50 °C |
Digital Delay and Pulse Generators
The Stanford Research Systems DG535 serves as an industry standard for precision timing applications, such as laser triggering and chemical kinetics. It features four independent delay channels (A, B, C, and D) and provides either four precisely-timed logic transitions or two independent pulse outputs. The instrument delivers a wide delay range of 0 to 1000 seconds with an exceptionally fine delay resolution of 5 ps.
With an insertion delay of approximately 85 ns from an external trigger to the T0 output, the DG535 supports triggering rates from 1 mHz to 1 MHz. Output formats include TTL, ECL, NIM, and variable levels ranging from -3 V to +4 V, allowing integration into diverse logic environments.
Synthesized Function and Arbitrary Generators
For general-purpose signal sourcing, SRS utilizes Direct Digital Synthesis (DDS) to deliver phase-continuous waveforms with 1 µHz frequency resolution. The range is structured by frequency limits and arbitrary waveform capabilities:
- Stanford Research Systems DS335: A compact 3.1 MHz synthesized function generator offering basic sine and square waves up to 3.1 MHz, ramps up to 10 kHz, and a 10 MHz white noise source.
- Stanford Research Systems DS340: A 15 MHz generator that adds arbitrary waveform capabilities (up to 40 MSamples/s sampling rate, 12-bit vertical resolution, and 16,300 points) and supports Gaussian noise.
- Stanford Research Systems DS345: A high-performance 30 MHz generator offering sine and square waves up to 30.2 MHz, ramps up to 100 kHz, and standard arbitrary waveform functions alongside a 10 MHz white noise source.
Low-Distortion Audio and Analog Testing
When testing high-fidelity audio equipment or sensitive analog circuitry, standard DDS generators may lack the necessary noise performance. The Stanford Research Systems DS360 is specifically designed for these applications, combining 20-bit D/A conversion with dedicated analog circuitry. It operates from 10 mHz to 200 kHz for both sine and square waves.
The DS360 achieves a typical total harmonic distortion (THD) of -110 dB at frequencies below 5 kHz. It also offers balanced outputs (up to 80.0 Vpp) and unbalanced outputs (up to 40.0 Vpp), making it suitable for professional audio and precise calibration work.
Popular models
Frequently asked questions
- How do the output channels of the DG535 operate?
- The DG535 features four independent delay channels (A, B, C, and D) that can be linked to T0 or any other delay channel. This delay linking allows users to build complex timing configurations across a 0 to 1000 second range with 5 ps resolution.
- Which SRS generators support arbitrary waveforms?
- The DS340 and DS345 support arbitrary waveform generation. The DS340 features a 40 MSamples/s playback rate with 12-bit vertical resolution and a maximum waveform length of 16,300 points, allowing user-defined shapes to be loaded via GPIB or RS-232.
- What is the primary advantage of the DS360 over the DS345?
- While the DS345 covers a wider frequency range up to 30.2 MHz, the DS360 is optimized for low-distortion audio and precision analog work. The DS360 offers ultra-low THD (typical -110 dB below 5 kHz), balanced outputs up to 80 Vpp, and a 20-bit D/A converter, whereas the DS345 is a standard DDS function generator.