Throughput rate to pc (usb or wireless), Digital input/output – Measurement Computing WLS-TEMP User Manual

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WLS-TEMP Specifications

Note 12:

Resistance values greater than 180 kΩ cannot be measured by the device in the thermistor mode.

The 180 kΩ resistance limit includes the total resistance across the current excitation (±Ix) pins, which
is the sum of the thermistor resistance and the lead resistances.

Note 13:

For accurate three wire compensation, the individual lead resistances connected to the ±Ix pins

must be of equal value.

Throughput rate to PC (USB or wireless)

Table 9. Throughput rate specifications

Number of input channels

Maximum throughput

2 Samples/second

2 S/s on each channel, 4 S/s total

2 S/s on each channel, 6 S/s total

2 S/s on each channel, 8 S/s total

2 S/s on each channel, 10 S/s total

2 S/s on each channel, 12 S/s total

2 S/s on each channel, 14 S/s total

2 S/s on each channel, 16 S/s total

Note 14:

The analog inputs are configured to run continuously. Each channel is sampled twice per second.

The maximum latency between when a sample is acquired and the temperature data is provided by the
device is approximately 0.5 seconds

Digital input/output

Table 10. Digital input/output specifications

Parameter

Specification

Digital type

CMOS

Number of I/O

8 (DIO0 through DIO7)

Configuration

Independently configured for input or output.
Power on reset is input mode unless bit is configured for alarm.

Pull up/pull-down
configuration

All pins pulled up to +5 V via 47 kΩ resistors (default). Pull down to ground (GND) also
available.

Digital I/O transfer rate
(software paced)

 Digital input: 50 port reads or single bit reads per second, typ
 Digital output: 100 port writes or single bit writes per second, typ

Input high voltage

2.0 V min, 5.5 V absolute max

Input low voltage

0.8 V max, –0.5 V absolute min

Output low voltage
(IOL = 2.5 mA)

0.7 V max

Output high voltage
(IOH = –2.5 mA)

3.8 V min

Note 15:

All ground pins are common and are isolated from earth ground. If a connection is made to earth

ground when using digital I/O and conductive thermocouples, the thermocouples are no longer
isolated. In this case, thermocouples must not be connected to any conductive surfaces that may be
referenced to earth ground.