contains the ALD500R/ALD521D A/D Converter chipset that directly plugs into the parallel printer port
of a PC computer. It features calibrated analog input (w/scalable input ranges), and digital circuitry to
communicate with PC or other microprocessors. It is designed to be used as a stand-alone, embedded
system component in a variety of applications including digital panel meters, customized instrumentation
displays, temperature monitoring, high resolution DVM’s, weigh scales and others. Direct Full-scale
analog input range is +/- 2.00000 V DC with a linearity of 0.005%. ALD's 18-bit plus sign integrating
dual-slope analog processor (ALD500) functions as the input device and the ALD521D microprocessor
IC implements the digital conversion, control mode and I/O functions.
configurations, are: Mode A version- calibrated reference and Mode B version – ratio-metric. Mode A is
used primarily for measurements against a calibrated reference voltage typically required in precision
voltmeter applications. Mode B is intended for measurements against a ratio-metric reference voltage
such as those required in weigh scale applications. Standard Mode A version is available as MB1S. Mode
B is a simple application specific adaptation of the standard MB1S.
The MB1S board has provision for PC interface, included DOS setup, operating and calibration software,
Basic programming interface modules, and input resistor divider network for input scaling. DC Inputs are
single ended or optionally fully differential, and features automatic zero and automatic input polarity
detection. A DB25 connector is provided on-board to conveniently interconnect the MB1S to a personal
computer (PC) via the parallel printer port for operation, initial setup and calibration.
Hardware and Software Features
• Directly plug into a PC parallel printer port and displays readings on the monitor.
• Measurement Range: +/- 2.00000 VDC direct input.
• Self-powered from PC computer or external +5 VDC power source
• All solid-state construction.
• 24 bit serial output. (23 bit plus sign bit)
• User selectable +/- 3 1/2 to +/- 6 1/2 digits.
• Differential analog inputs with auto-polarity and auto-zero.
• Simple to install and operate.
• Includes DOS software for user operation, setup, and calibration.
• Includes embedded application software modules.
• Calibration for positive and/or negative inputs.
• Provision for input voltage scaling attenuator network.
• Smart Input Filtering (Sample Averaging) selection for noise reduction and accurate displays.
MB1S © © © © 2003 Advanced Linear Devices, Inc., 415 Tasman Drive, Sunnyvale, California 94089-1706, Tel: (408) 747-1155,
Fax: (408) 747-1286
(Other ranges are user configurable and scalable, using both hardware and software scaling)
The ALD MB1S is a precision +/- 5 ½-digit Digital Voltmeter (DVM) printed circuit board that
Two optional versions of the basic MB1S, each populated with different components and
Single Board Precision DVM with direct PC Interface
http://www.aldinc.com
MB1S(MB1SA2V)/MB1SA20V
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