USB-1608G Series User's Guide
Functional Details
15
An example of a 4-element list is shown in the table below.
Sample channel gain queue list
Element
Channel
Range
Mode
0
CH5
BIP5V
SE
1
CH1
BIP10V
DIFF
2
CH15
BIP1V
SE
3
CH5
BIP5V
SE
Carefully match the gain to the expected voltage range on the associated channel or an over range condition
may occur. Although this condition does not damage the device, it does produce a useless full-scale reading,
and can introduce a long recovery time due to saturation of the input channel.
For more information about analog signal connections
For more information about analog input connections, refer to the
Guide to Signal Connections
(this document
is available on our web site at
www.mccdaq.com/signals/signals.pdf
Analog output (USB-1608GX-2AO only)
The USB-1608GX-2AO has two 16-bit analog outputs (
AOUT0
and
AOUT1
). Both outputs can be updated
simultaneously at a rate of 250 kS/s per channel. One output can be updated at a rate of 500 kS/s. The output
range is fixed at ±10 V. The outputs default to 0 V when the host computer is shut down or suspended, or when
a reset command is issued to the device.
External clock I/O
USB-1608G Series devices provide one external clock input (
AICKI
) and one external clock output (
AICKO
) for
analog inputs.
The USB-1608GX-2AO also has one external clock input (
AOCKI
) and one external clock output (
AOCKO
) for
analog outputs.
You can connect an external clock signal to
AICKI
and/or
AOCKI
.
When using an external clock,
AICKO
outputs the pulse generated from
AICKI
.
When using a USB-1608GX-2AO, the
AOCKO
pin outputs the pulse generated from
AOCKI
.
When using the internal clock,
AICKO
outputs the
ADC scan clock.
When using a USB-1608GX-2AO,
AOCKO
outputs the
DAC scan clock.
Digital I/O
You can connect up to eight digital I/O lines to
DIO0
through
DIO7
. Each digital channel is individually
configurable for input or output. The digital I/O terminals can detect the state of any TTL-level input. Refer to
the schematic shown in Figure 7.
Figure 7. Schematic showing switch detection by digital channel DIO0
If you set the switch to the +5 V input, DIO0 reads
TRUE
(1). If you move the switch to GND, DIO0 reads
FALSE
(0).
