Analog Output Calibration; Digital Input/Output - Measurement Computing USB-3102 User Manual

USB-3102 User's Guide
Note 5: Each of the four DAC8554 outputs controls a VOUTx and IOUTx channel-pair simultaneously.
So, for example, when writing to channel VOUT0, the associated IOUT0 channel will also be
updated. Conversely, when writing to channel IOUT0, the associated VOUT0 channel is also
updated. Unused VOUTx and IOUTx output channels should be left disconnected.
The following formula will calculate the maximum load resistance for correct IOUT circuit
Note 6:
operation. The compliance voltage applied should not exceed the limits specified in Table 5.
Note 7: The maximum differential non-linearity specification applies to the entire 0 to 70 °C temperature
range of the USB-3102. This specification also accounts for the maximum errors due to the
software calibration algorithm (in Calibrated mode only) and the DAC8554 digital to analog
converter non-linearities.

Analog output calibration

Parameter
Recommended warm-up time
On-board precision reference
Calibration method
Calibration interval

Digital input/output

Digital logic type
Number of I/O
Configuration
Pull-up/pull-down configuration
(Note 8)
Digital I/O input loading
Digital I/O transfer rate (system paced)
Input high voltage
Input low voltage
Output high voltage (IOH = –2.5 mA)
Output low voltage (IOL = 2.5 mA)
Power on and reset state
Note 8: Pull up and pull down configuration area available using the DIO CTL terminal block pin 54.
The pull down configuration requires the DIO CTL pin (pin 54) to be connected to a DGND pin
(pin 50, 53 or 55). For a pull up configuration, the DIO CTL pin should be connected to the +5V
terminal pin (pin 56).

Calibrated Output:
Load Resistance = (Compliance Voltage - 6V)/0.020A

Un-Calibrated Output:
Load Resistance = (Compliance Voltage - 6V)/0.025A
Table 6. Analog output calibration specifications
Conditions
Table 7. Digital I/O specifications
CMOS
8
Independently configured for input or output
User configurable
All pins floating (default)
TTL (default)
47K ohms (pull-up/pull down configurations)
System dependent, 33 to 1000 port reads/writes or single bit reads/writes per
second.
2.0 V min, 5.5 V absolute max
0.8 V max, –0.5 V absolute min
3.8 V min
0.7 V max
Input
Specifications
15 minutes min.
DC level: 5.000 V ±1 mV max.
Tempco: ±10 ppm/°C max.
Long term stability: ±10 ppm/SQRT(1000 hrs)
Software calibration
1 year
21
Specifications