The Stanford Research Systems DS345 is a 30 MHz synthesized function and arbitrary waveform generator based on an innovative Direct Digital Synthesis (DDS) architecture. It generates standard waveforms with excellent 1 µHz frequency resolution, wideband noise, and arbitrary waveforms updated at a fast 40 MSa/s rate. The instrument features comprehensive modulation options including AM, FM, Phase Modulation (PM), Burst, and phase-continuous frequency sweeps.
Specifications
Physical
| Parameter | Value |
|---|---|
| Power Supply | 50 W, 100/120/220/240 VAC, 50/60 Hz |
| Operating Temperature | 0 to 50 |
| Dimensions (W×H×D) | 216 × 89 × 330 |
| Weight | 4.5 |
Waveforms
| Parameter | Value |
|---|---|
| Standard Waveforms | Sine, Square, Triangle, Ramp |
| Arbitrary Waveforms | Yes |
| Noise Mode | White Noise |
Frequency Characteristics
| Parameter | Value |
|---|---|
| Sine Range | 1 µHz to 30.2 MHz |
| Square Range | 1 µHz to 30.2 MHz |
| Triangle Range | 1 µHz to 100 kHz |
| Ramp Range | 1 µHz to 100 kHz |
| Noise Bandwidth | 10 MHz |
| Frequency Resolution | 1 µHz |
Amplitude and Output
| Parameter | Value |
|---|---|
| Amplitude Range (50 Ohms) | 10 mVpp to 10 Vpp |
| Amplitude Resolution | 3 digits |
| Output Impedance | 50 Ω |
| Output Floating Range | Up to ±40 V relative to earth ground |
| Display Formats | Vpp, Vrms, dBm |
Arbitrary Waveform Capabilities
| Parameter | Value |
|---|---|
| Sample Rate | 40 MSa/s |
| Waveform Memory Length | 16,300 points |
| Vertical Resolution | 12 bits |
Modulation
| Parameter | Value |
|---|---|
| Internal Source Frequency | 1 mHz to 10 kHz |
| AM Depth | ±100 % (1 % resolution) |
| FSK/BPSK Rate (Internal) | 0.001 Hz to 50 kHz |
| External AM Input Range | ±5 V for 100% modulation |
| External AM Bandwidth | 15 kHz |
Sweep
| Parameter | Value |
|---|---|
| Sweep Type | Linear or Logarithmic |
| Sweep Direction | Up or Down |
| Sweep Continuity | Phase-continuous |
| Sweep Time | 0.001 s to 1000 s |
Burst
| Parameter | Value |
|---|---|
| Burst Maximum Frequency (Sine/Square) | 1 MHz |
| Burst Maximum Frequency (Triangle/Ramp) | 100 kHz |
Inputs and Outputs
| Parameter | Value |
|---|---|
| Main Output Connector | Front-panel BNC (floating) |
Timebase
| Parameter | Value |
|---|---|
| Frequency Accuracy | ±5 ppm (20 °C to 30 °C) |
Phase
| Parameter | Value |
|---|---|
| Phase Control Range | ±7199.999° |
| Phase Control Resolution | 0.001° |
Square Wave Characteristics
| Parameter | Value |
|---|---|
| Square Wave Rise/Fall Time | < 15 ns (10 % to 90 %) |
| Square Wave Asymmetry | < 1 % of period + 4 ns |
| Square Wave Overshoot | < 5 % of peak-to-peak amplitude |
Triangle/Ramp Wave Characteristics
| Parameter | Value |
|---|---|
| Triangle/Ramp Linearity | > 99 % (up to 100 kHz) |
Arbitrary Wave Characteristics
| Parameter | Value |
|---|---|
| Arbitrary Waveform Rise/Fall Time | < 35 ns |
Amplitude & Offset
| Parameter | Value |
|---|---|
| DC Offset Range (50 Ω) | ±5 V |
| DC Offset Range (High Z) | ±10 V |
| DC Offset Accuracy | 1.5 % of setting + 20 mV |
Spectral Purity (Sine)
| Parameter | Value |
|---|---|
| Harmonic Distortion (DC to 1 MHz) | < -55 dBc |
| Harmonic Distortion (1 MHz to 10 MHz) | < -45 dBc |
| Harmonic Distortion (10 MHz to 30 MHz) | < -35 dBc |
Signal Quality
| Parameter | Value |
|---|---|
| Phase Noise | < -110 dBc/Hz (10 kHz offset, 5 MHz carrier) |
| Spurious (DC to 1 MHz) | < -65 dBc |
| Spurious (1 MHz to 15 MHz) | < -55 dBc |
| Spurious (15 MHz to 30 MHz) | < -45 dBc |
Burst Mode
| Parameter | Value |
|---|---|
| Burst Count | 1 to 30,000 cycles |
Inputs & Outputs
| Parameter | Value |
|---|---|
| External Reference Input Frequency | 10 MHz |
Technology
Direct Digital Synthesis (DDS)
Applications
Test & Measurement