Acqutek - PA-AD12(-H) (details)
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Similar / Related Products PI-IO48A - PA-CP12 - PA-ST12(-H) - PA-MA12(-H) - PA-MD12(16) - PA-AD12(-H) - PA-DA12(16)
XC-IO96 - XC-AD12 - XC-DA12
XI-PI08 - XI-IM04 - XO-RR08 - XO-SRD4/XO-SRA4 - ST-XD02 - ST-DM37 - IC-XCXD

PA-AD12(-H) Brief Description
Analog to Digital Card

Description - Model No - Expansion - Block Diagram - Function - Register - Programming - Specifications


    20us (PA-AD12), 10us (PA-AD12-H) analog to digital (A/D) converter.
    12-Bit A/D converter with 1 LSB accuracy.
    8 differential or 16 single-ended analog input channels.
    8254 timer provides background A/D conversion.
    Jumper-configuration gain controller.
    DC/DC converter to reduce noise from PC.


    For users who require A/D only, we've got a card for you. The PA-AD12 and PA-AD12-H are 12 bit analog to digital converters.

    The PA-AD12 and PA-AD12-H have 8 differential/16 single-ended input channels with 12 bit 20us/10us A/Ds. An 8254 Timer/Counter, on board, allows background conversions.

    This module also comes with jumper-configurable gain control that allows the user to select the gain.


    Function PA-AD12 PA-AD12-H
    A/D Resolution 12 Bit 12 Bit
    Channels 8 Differential or 16 Single-ended 8 Differential or 16 Single-ended
    Conversion time 20 us 10 us
    Accuracy 11 Bit 11 Bit


    Model No. Function
    ST-DM37 Screw terminal board for A/D D/A connector
    IC-XCXD Chassis for XCI/XDI expansion cards



    The signal connector - The signal connector is a 37 pin D-type male connector.

    A/D channel selection - The PA-AD12(-H) can be configured for 8 differential inputs or 16 single-ended inputs. The configuration is set by an on-board jumper, the channel is software selectable. (base+2 port)

    Sample and hold - The PA-AD12(-H) uses a sample and hold circuit that depends on the end of conversion signal from the A/D chip. Thus, the sample and hold rate is a function of the A/D conversion speed.

    A/D conversion control - The A/D conversion can be triggered in three ways, they can be selected by writing a command to the A/D command port (base+3).

      Trigger method 1 : S/W trigger conversion
      This method of conversion is very easy to implement because the software is directly controlling the A/D conversions.
      Trigger method 2 : External clock conversion
      The external clock conversion consists of using an external clock or pulse, longer than 200 nanoseconds, to trigger the A/D conversion. This gives the user great flexibility in providing a trigger signal that enables one to synchronize the A/D with other devices.
      Trigger method 3 : 8254 timer conversion
      Timer conversion use the 8254 to generate a clock pulse that enablesconversion to be done in the background leaving the CPU to do more important tasks.

    A/D conversion When an A/D conversion takes place, (by software trig, external clock trig, etc.) the EOC (End Of Conversion) line goes high. Once the signal is received, conversion of the voltage held by the sample and hold unit is initiated. Once the converison is initiated (EOC is high), no other start conversion command will be accepted until the completion of the conversion.

    Upon completion of the conversion, the EOC line goes low (in timer or external clock trig mode, an interrupt will occurred). Next, the least significant byte (LSB) and the most significant byte (MSB) of the digital value for the voltage can be read from the data registers, base+0 and base+1 respectively.

    The 8 bits of the base+1 port are the 8 most significant bits of the A/D conversion result. The 4 most significant bits of the base+0 port are the 4 least significant bits of the A/D conversion

    Reading conversion result - The conversion status of the A/D can be read from the status port.


    +0 02E0HI/O readA/D LSB data
    I/O writeStart A/D conversion
    +1 02E1HI/O readA/D MSB data
    I/O writeNone
    +2 02E2HI/O readA/D channel select
    I/O write
    +3 02E3HI/O readA/D status
    I/O writeA/D command
    +12 02ECHI/O read8254 counter 0 data (A/D internal use)
    I/O write
    +13 02EDHI/O read8254 counter 1 data (A/D timer conversion)
    I/O write
    +14 02EEHI/O read8254 counter 2 data (A/D timer conversion)
    I/O write
    +15 02EFHI/O read8254 read-back status
    I/O write8254 command


    Shipped with this board are Utility, Library and Sample Programs. These programs are included with the product at no additional expense.

    Utility Program - This program will provide comprehensive testing of various functions of the board to ensure proper operation.
    Library And Sample Programs - The library program provides the interface to Turbo-C, Microsoft Quick Basic, Microsoft Quick C, Microsoft GW-BASIC, IBM BASIC and Assembler.
    Labtech Notebook Driver - A Labtech's Notebook driver interface is available as an optional product.
    Window Driver - Window 3.1 and Window NT driver interface is available as an optional product.


    Analog Inputs (A/D)
    Resolution 12 bits
    Input channel 16 channels (single-ended)
    8 channels (differential)
    Input voltage range -5V to +5V, -10Vto +10V
    0V to +5V, 0V to +10V
    Accuracy 1 bit
    Conversion time 20us(PA-AD12)
    10us (PA-AD12-H)
    Overvoltage 35V
    Gain controller 1, 2, 5, 10, 20, 50 or user define
    by H/W jumper setting
    Conversion method S/W trig
    External clock trig
    Internal 8254 timer trig
    Connector 37 pins D-type male connector
    Counter Timer (CLK)
    Controller 8254
    Counters 3 16-bit down counter
    2 for A/D timer conversion
    1 for user's application
    Clock source 4 MHz
    Input/output type TTL
    Interface Characters
    Compatible bus IBM PC and compatibles
    Data path 8 bits
    Interface type 12 Bit I/O mapped
    I/O location occupied 8
    Port address range 100H to FF0H
    Interrupt IRQ2,3,4,5,7,10,11,12,14,15
    Interrupt source A/D end of conversion (EOC)
    Power requirement 1.25A / +5V
    Operating temperature +5 ° C to +50 ° C
    Humidity 0 to 90% non-condensing
    Weight 175 g
    Dimension 17.5 x 12.6 x 2.0 cm

Copyright © 1996 - 2000 by Acqutek Corporation, Inc.