IBM pc-card das16 User Manual

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PC-CARD-DAS16/16AO User's Guide 
Specifications 
Analog output 
Table 6. Analog output specifications 
D/A converter type 
LTC1655 
Resolution 16 
bits 
Number of channels 
Configuration 
Voltage output, single-ended 
Output range 
±10 V 
D/A pacing 
Software 
Data transfer 
Programmed I/O 
Throughput 
System dependent. Using the Universal Library programmed output 
function (cbAout) in a loop in Visual Basic, a typical update rate of 
1.5 kHz (±200 Hz) can be expected. The rate was measured on a 
400 MHz Pentium II based PC. 
Accuracy 
Table 7. Accuracy specifications 
Absolute accuracy 
±12.0 LSB worst case error 
Typical accuracy 
±10.0 LSB worst case error 
Table 8. Calibrated accuracy components 
Gain error 
±3.0 LSB max, ±1.0 LSB typ 
Offset error 
±1.5 LSB max, ±0.5 LSB typ 
Integral linearity error 
±20.0 LSB max, ±8.0 LSB typ 
Differential linearity error 
±1.0 LSB max, ±0.3 LSB typ 
Each PC-CARD-DAS16/16AO is tested at the factory to assure the board’s overall error does not exceed 
±12.0 LSB.  
Total board error is a combination of gain, offset, integral linearity and differential linearity error. The 
theoretical worst-case error of the board may be calculated by summing these component errors. Worst case 
error is realized only in the unlikely event that each of the component errors are at their maximum level, and 
causing error in the same direction. Although an examination of the chart and a summation of the maximum 
theoretical errors shows that the board could theoretically exhibit a ±25.5 LSB error, our testing assures this 
error is never realized in a board that we ship. 
Typical accuracy is derived directly from the various component typical errors. This typical, maximum error 
calculation for the PC-CARD-DAS16/16AO yields ±10.0 LSB. However, this again assumes that each of the 
errors contributes in the same direction and the ±10.0 LSB specification is quite conservative. 
Monotonicity Guaranteed 
monotonic over temperature  
Analog output full-scale gain drift 
±5.0 LSB/°C max 
Analog output zero drift 
±0.5 LSB/°C max 
Overall analog output drift 
±5.5 LSB/°C max 
Slew rate 
± 0.7 V/µs min 
Current drive 
±2 mA min 
Output short-circuit duration 
Indefinite @ 12 mA 
Output coupling 
DC 
Output impedance 
0.1 ohms max 
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