User manual

PCI-DA12-8/16 Manual
Page 1-2
Manual MPCI-DA12-16.Dh
Each I/O line is buffered by a type 74LS245 tristate buffer transceiver capable of sourcing 15 mA or
sinking 24mA (64 mA on request as a factory installed option). Pull-ups on the card assure that there
are no erroneous outputs at power up. The buffers are configured automatically by hardware logic for
input or output according to direction assignment from a control register in the PPI.
The PCI-DA12-8/16 contain a type 82C54 counter/timer which has three 16-bit programmable down
counters. Counter/Timer #0 and Counter/Timer #1 are configured for event counting. Counter/Timers
#1 and #2 are concatenated and form a 32-bit counter/timer for frequency generation. The dual
counter/timer is clocked by a 1 MHZ crystal oscillator and may be gated on/off by a CMOS level
signal at the connector. The counters can also be programmed to provide a “clock-tick” interrupt and
update of the DAC buffers for more precisely timed outputs.
Specifications
Analog Outputs
• Resolution: 12 Binary bits (0 to 4095 decimal).
• Channels: 16 or 8 Voltage output or Current sink channels.
• Current Range: 4 to 20 mA.(with excitation voltage 8-36 VDC)
• Voltage ranges (5mA max): 0V to +2.5V.
0V to +5V.
0V to +10V.
-2.5V to +2.5V.
-5V to +5V.
-10V to +10V.
AD7237 D/A Converter, Double Buffered / Simultaneous Update
• Relative Accuracy: ± ½ LSB.
• Monotonicity: 12 bits over operating temperature range.
• Settling Time: 8 usec to one LSB for full-scale step input.
• Linearity: ± ½ LSB integral non-linearity over rated temperature range.
• Gain Stability: 15 ppm/ °C.
• Output Drive Capability: 5mA maximum.
• Short-Circuit Current: 25 mA maximum.
• Output Resistance: Less than 0.1 S.
• Data Format: 12-bit binary, right justified, and offset binary for bipolar
outputs.