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Digital i/o – Measurement Computing USB-1408FS User Manual

Page 22

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USB-1408FS User's Guide

Specifications

22

Table 7. Analog output accuracy

Range

Accuracy (±LSB)

0 V to 4.096 V

4.0 typ, 45.0 max

Table 8. Analog output accuracy components

Range

% of FSR (±)

Gain Error at FS (±mV)

Offset (±mV)

(Note 6)

Accuracy at FS (±mV)

0 V to 4.096 V

0.1 typ, 0.9 max

4.0 typ, 36.0 max

1.0 typ, 9.0 max

4.0 typ, 45.0 max

Note 6:

Zero-scale offsets may result in a fixed zero-scale error producing a "dead-band” digital input code
region.. In this case, changes in digital input code at values less than 0x040 may not produce a
corresponding change in the output voltage. The USB-1408FS offset error is tested and specified at
code 0x040.

Digital I/O

Table 9. Digital I/O specifications

Parameter

Specification

Digital type

CMOS

Number of I/O

16 (Port A0 through A7, Port B0 through B7)

Configuration

2 banks of 8

Pull-up/pull-down configuration

All pins pulled up to 5V via 47 k

Ω resistors (default).

Hardware with p/n 193331x (where x is the revision letter) may be changed to
pull-down using an internal jumper.
Other hardware versions can be configured for pull-down at the factory.

Input high voltage threshold

2.0 V min

Input high voltage limit

5.5 V absolute max

Input low voltage threshold

0.8 V max

Input low voltage limit

–0.5 V absolute min
0 V recommended min

Output high voltage
(IOH = –6.0 mA)

3.84 V min

Output low voltage
(IOL = 6.0 mA)

0.33 V max

Power on and reset state

Input