DCX-127 Multifunction Module


DCX-127 Multifunction Module
Providing non-audio functionality & interface capabilities for typical audio test setups

The DCX-127 Multifunction Module provides Audio Precision’s PC-controlled audio analyzers with an interface toolkit of non-audio functions and interface capabilities that are often required in typical audio test applications.

• DC voltage and resistance measurements auto-ranging from 200 mV to 500 V and 200 Ω to 2 MΩ full scale, fully floating and protected to provide accurate measurements in the presence of large common mode voltages
• Resistance measurements using either 4-wire or 2-wire techniques
• Two independently-programmable, bipolar floating DC voltage outputs, each with a ±10.5 V range
• 20 mV resolution and monotonicity to 40 mV (19 bits)
• Software can sweep either DC source
• Digital input of static or low-speed parallel input, word width up to 21 bits
• Digital output of a parallel digital word of 21 bits
• Simplified 8-bit program control interface can be defined to execute any pre-defined keystroke sequence, to run different software procedures based upon switch closures

The module contains a 4-1/2 digit DC voltmeter-ohmmeter, two 20-bit programmable DC voltage sources, 21 bits of digital I/O, and four 8-bit programmable auxiliary output ports for device control or status indicators. Typical applications include VCA gain control linearity, VCA distortion, amplifier DC offset and power supply checks, power amplifier load switching control, loudspeaker voice coil resistance measurements, temperature measurements, test fixture control, and testing DC parameters of A/D and D/A converters.
The DCX-127 also provides pulses and DC levels whose timing depend upon key software actions such as end of sweep, analyzer channel selection, or data settling. These may be used for synchronization and sequencing of external devices or portions of the test system such as the triggered sine burst generator.

All DCX-127 output functions are under analyzer software control, and all of the inputs are displayed in the control software and can be displayed as bar graphs or plotted values during a sweep when appropriate.

NOTE: Use of the DCX-127 Multifunction Module with APx500 Series audio analyzers requires an APIB adapter (USB, PCI or PCMCIA).