Bruel & Kjaer 3105 30 kHz Output Module

The Brüel & Kjaer 3105 is a 30 kHz output module delivering precision signal generation for acoustic and vibration measurement systems. This 24-bit D/A converter produces signals up to 25.6 kHz with three selectable output voltage ranges: 70.7 mVpeak, 707 mVpeak, and 7.071 Vpeak into 50 Ω impedance. Integrated with downloadable DSP functionality, the module generates sine, dual sine, multisine, random, pseudo-random, periodic random, pulse, and user-defined waveforms with built-in trigger capability. The long output buffer accommodates up to 4096k samples, supporting both ground-referenced and floating signal configurations with automatic DC-offset compensation. When integrated into multichannel systems like the Type 3561 IDA platform, the 3105 pairs with four independent input channels featuring CCLD (BNC and LEMO) connectors, transducer remote ID support via µLAN, cable fault detection using dual current method, and settable high-pass filters at DC, 0.7 Hz, and 22.4 Hz. Input ranges are independently selectable with autorange capability. Common-mode rejection reaches 50 dB from 1 Hz to 1 kHz and 40 dB from 1 kHz to 25.6 kHz. The antialiasing filter spans DC to 25.6 kHz at -0.1 dB with an -18 dB/octave slope.

Technical Specifications

Maximum output frequency: 25.6 kHz

Output coupling: DC direct (fL = 0 Hz)

Output voltage ranges: 70.7 mVpeak, 707 mVpeak, 7.071 Vpeak

Output impedance: 50 Ω

D/A conversion: 24-bit

Output buffer: Up to 4096k samples (shared memory)

Output levels: 5 mV to 5 V (hardware adjustable)

Input channels: 4 independent

Input connectors: CCLD (BNC and LEMO) per channel

High-pass filter options: DC, 0.7 Hz, 22.4 Hz

Common-mode rejection: 50 dB (1 Hz to 1 kHz); 40 dB (1 kHz to 25.6 kHz)

Maximum induced common-mode voltage: 1 Vpeak (DC to 4 MHz); 10 Vrms (4 MHz to 80 MHz)

Antialiasing filter: DC to 25.6 kHz @ -0.1 dB, -18 dB/octave slope

Key Features

Downloadable waveform library: sine, multisine, random, pseudo-random, periodic random, pulse, user-defined

Transducer remote ID support via µLAN interface

Dual-method cable fault detection

Overload detection with out-of-band frequency indication

Per-channel autorange capability

Long time records: up to 4096k samples total

Built-in digital signal processors

Automatic DC-offset compensation

Typical Applications

Acoustic and vibration measurement campaigns

System excitation and transducer response characterization

Multi-transducer data acquisition with mixed connector types

Sinusoidal and complex waveform signal generation

Compatibility & Integration The 3105 operates as a module within the Type 3561 Intelligent Data Acquisition System, leveraging application software to configure waveforms, filters, and signal processing parameters.