Macro Sensors LVDTs: DCM-1000 DC-Operated LVDT Signal Conditioner Module

Description

Macro Sensors' Model DCM-1000 is a low-cost, single-channel, board-level LVDT signal conditioner module designed primarily for incorporation into OEM products but also used by students and cost-sensitive end users. The DCM-1000 operates from ±15 Volts DC power and provides a low-noise 0 to ±10 Volts DC full-scale output suitable for inputing directly into PLCs, digital readouts, and data acquisition systems, as well as other signal processing and recording devices. This module provides a cost-effective high-performance alternative to in-house-designed electronics to support 4-, 5-, or 6-wire LVDTs or 3-wire half-bridge style LVRTs.

Utilizing modern, high-reliability, surface-mount construction, the DCM-1000 uses a time-proven ASIC that produces a low distortion sine wave to excite the LVDT and has a synchronous demodulator to convert the LVDT's AC output to a more useful bipolar DC voltage proportional to LVDT core position. Additional circuitry regulates the ASIC's DC operating power, enables on-board span and zero adjustability, and provides a 2-pole low pass output filter.

By shifting removable jumpers on the board, a user can choose 3, 5, or 10 kHz nominal excitation frequencies for driving the LVDT. Similarly, the user can select several coarse gain jumper settings, allowing a DCM-1000 to operate over more than a 50-to-1 range of full scale output signals from the LVDT.

As a result, a DCM can operate almost any LVDT or LVRT, regardless of sensitivity. And for multi-channel applications, a user can switch on-board jumpers to synchronize the oscillators of each module in a master-slave configuration, which minimizes beat frequencies, heterodyning, and inter-modulation and/or crosstalk between channels.

A key feature of the DCM-1000 is minimal interaction between the Zero and Span controls, which facilitates user calibration while providing maximum I/O flexibility. The DCM-1000's Zero control permits output offset adjustment from -100% to +100% of full scale, which allows a user to set up the module with a unipolar output of 0 to 10 Volts DC over the entire working range of the sensor. The DCM-1000 module requires no phase adjustment and works satisfactorily even with moderate length cables between it and most LVDTs.

The I/O and power connections to the DCM-1000 module can be hardwired to on-board solder terminals or to a card edge connector into which the module can be plugged. As an alternative to mounting using a card edge connector, the module can be mounted by two female-threaded standoffs attached to the pc board. In addition to the standard catalog version, the DCM-1000 module is available in custom configurations for OEMs or larger systems integrators who might need different I/O parameters, such as input power or excitation and filter cutoff frequencies, or a reduction in package size by trimming off the card edge connections.


click the image for an enlarged view General Specifications Mechanical Drawing & Wiring Diagram Accessories Ordering Information Tech Bulletin Instruction Manual	Description Macro Sensors' Model DCM-1000 is a low-cost, single-channel, board-level LVDT signal conditioner module designed primarily for incorporation into OEM products but also used by students and cost-sensitive end users. The DCM-1000 operates from ±15 Volts DC power and provides a low-noise 0 to ±10 Volts DC full-scale output suitable for inputing directly into PLCs, digital readouts, and data acquisition systems, as well as other signal processing and recording devices. This module provides a cost-effective high-performance alternative to in-house-designed electronics to support 4-, 5-, or 6-wire LVDTs or 3-wire half-bridge style LVRTs. Utilizing modern, high-reliability, surface-mount construction, the DCM-1000 uses a time-proven ASIC that produces a low distortion sine wave to excite the LVDT and has a synchronous demodulator to convert the LVDT's AC output to a more useful bipolar DC voltage proportional to LVDT core position. Additional circuitry regulates the ASIC's DC operating power, enables on-board span and zero adjustability, and provides a 2-pole low pass output filter. By shifting removable jumpers on the board, a user can choose 3, 5, or 10 kHz nominal excitation frequencies for driving the LVDT. Similarly, the user can select several coarse gain jumper settings, allowing a DCM-1000 to operate over more than a 50-to-1 range of full scale output signals from the LVDT. As a result, a DCM can operate almost any LVDT or LVRT, regardless of sensitivity. And for multi-channel applications, a user can switch on-board jumpers to synchronize the oscillators of each module in a master-slave configuration, which minimizes beat frequencies, heterodyning, and inter-modulation and/or crosstalk between channels. A key feature of the DCM-1000 is minimal interaction between the Zero and Span controls, which facilitates user calibration while providing maximum I/O flexibility. The DCM-1000's Zero control permits output offset adjustment from -100% to +100% of full scale, which allows a user to set up the module with a unipolar output of 0 to 10 Volts DC over the entire working range of the sensor. The DCM-1000 module requires no phase adjustment and works satisfactorily even with moderate length cables between it and most LVDTs. The I/O and power connections to the DCM-1000 module can be hardwired to on-board solder terminals or to a card edge connector into which the module can be plugged. As an alternative to mounting using a card edge connector, the module can be mounted by two female-threaded standoffs attached to the pc board. In addition to the standard catalog version, the DCM-1000 module is available in custom configurations for OEMs or larger systems integrators who might need different I/O parameters, such as input power or excitation and filter cutoff frequencies, or a reduction in package size by trimming off the card edge connections.	Features Support most standard LVDTs or LVRTs 0 to ±10 V DC or 0 to 10 V DC output. 50-to-1 full scale input sensitivity range. 3, 5 or 10 kHz sine wave excitation. Master/slave excitation synchronizing. Non-interactive span and zero adjustments. No demodulator phase adjustment needed.