SERIES IOS-320 I/O SERVER MODULE 12-BIT HIGH DENSITY ANALOG INPUT BOARD
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Acromag, Inc. Tel:248-295-0310 Fax:248-624-9234 Email:solutions@acromag.com http://www.acromag.com
The output of the PGA feeds the Analog to Digital Converter
(ADC). The A/D Converter is a state of the art, 12-bit, successive
approximation converter with a built-in Sample and Hold (S/H)
circuit. The S/H goes into the hold mode when a conversion is
initiated. This maintains the selected channel's voltage constant
until the A/D Converter has accurately digitized the input. Then it
returns to the sample mode to acquire the next channel. Once a
conversion has been started, the control register can be updated
for the next channel. This allows the input to settle for the next
channel while the previous channel is converting, which gives rise
to the pipelined mode of operation (and maximum system
throughput).
A miniature DIP switch on the board control the range
selection for the A/D Converter (-5 to +5, -10 to +10, or 0 to +10
Volts) as detailed in Section 2. DIP switch selection should be
made prior to powering the unit. Thus, all channels will use the
same A/D Converter range. However, the analog input range can
vary on an individual channel basis depending on the
programmable gain selection.
The logic interface provides 12 Volt supplies to the analog
circuitry. The -10 to +10 and 0 to +10 Volt A/D Converter ranges
will be clipped if these supplies are used, typically to 9 Volt
maximum inputs. The user has the option of providing 15 Volt
external supplies to fully utilize input ranges to 10 Volts. These
supplies are selected via hardware jumpers J1 and J2 as detailed
in Section 2. Note that jumper selection should be made prior to
powering the unit. Further, internal and external supplies should
not be mixed (e.g. do not use +12 Volts with -15 Volts).
The board contains four precision voltage references and a
ground (autozero) reference for use in calibration. These provide
considerable flexibility in obtaining accurate calibration for any
desired ADC range and gain combination, when compared to
fixed hardware potentiometers for offset and gain calibration of
the ADC and PGA. The calibration signals are selected
(multiplexed into the PGA) like any other input channel.
5.0 SERVICE AND REPAIR
SERVICE AND REPAIR ASSISTANCE
Surface-Mounted Technology (SMT) boards are generally
difficult to repair. It is highly recommended that a non-functioning
board be returned to Acromag for repair. The board can be
damaged unless special SMT repair and service tools are used.
Further, Acromag has automated test equipment that thoroughly
checks the performance of each board. When a board is first
produced and when any repair is made, it is tested, placed in a
burn-in room at elevated temperature, and retested before
shipment.
Please refer to Acromag's Service Policy Bulletin or contact
Acromag for complete details on how to obtain parts and repair.
PRELIMINARY SERVICE PROCEDURE
Before beginning repair, be sure that all of the procedures in
Section 2, Preparation For Use, have been followed. Also, refer
to the documentation of your carrier board to verify that it is
correctly configured. Verify that there are no blown fuses.
Replacement of the carrier and/or IOS with one that is known to
work correctly is a good technique to isolate a faulty board.
CAUTION: POWER MUST BE TURNED OFF BEFORE
REMOVING OR INSERTING BOARDS
WHERE TO GET HELP
If you continue to have problems, your next step should be to
visit the Acromag worldwide web site at
http://www.acromag.com
.
Our web site contains the most up-to-date product and software
information.
Go to the “Support” tab to access:
Application Notes
Frequently Asked Questions (FAQ‟s)
Product Knowledge Base
Tutorials
Software Updates/Drivers
An email question can also be submitted from within the
Knowledge Base or directly from the “Contact Us” tab.
Acromag‟s application engineers can also be contacted
directly for technical assistance via telephone or FAX through the
numbers listed below. When needed, complete repair services
are also available.
Phone: 248-295-0310
Fax: 248-624-9234
Email:
solutions@acromag.com
