Measurement Computing Corporation, InstaCal, Universal Library, and the Measurement Computing logo are
either trademarks or registered trademarks of Measurement Computing Corporation. Refer to the Copyrights &
Trademarks section on mccdaq.com/legal
for more information about Measurement Computing trademarks.
Other product and company names mentioned herein are trademarks or trade names of their respective
companies.
Measurement Computing Corporation does not authorize any Measurement Computing Corporation product for
use in life support systems and/or devices without prior written consent from Measurement Computing
Corporation. Life support devices/systems are devices or systems that, a) are intended for surgical implantation
into the body, or b) support or sustain life and whose failure to perform can be reasonably expected to result in
injury. Measurement Computing Corporation products are not designed with the components required, and are
not subject to the testing required to ensure a level of reliability suitable for the treatment and diagnosis of
people.
2
Table of Contents
Preface
About this User's Guide ....................................................................................................................... 5
What you will learn from this user's guide ......................................................................................................... 5
Conventions in this user's guide ......................................................................................................................... 5
Where to find more information ......................................................................................................................... 5
Chapter 1
Introducing the USB-1808X .................................................................................................................. 6
Installing the software ........................................................................................................................................ 7
Installing the hardware ....................................................................................................................................... 7
Calibrating the hardware..................................................................................................................................... 7
USB connector .................................................................................................................................................................. 8
Analog input ..................................................................................................................................................... 10
Analog output ................................................................................................................................................... 11
Digital I/O ......................................................................................................................................................... 11
Digital input scanning ......................................................................................................................................................11
Period measurement mode ...............................................................................................................................................13
Digital triggering .............................................................................................................................................. 15
Power output ..................................................................................................................................................... 16
Analog input ..................................................................................................................................................... 18
Analog input DC voltage measurement accuracy ............................................................................................................19
Analog output ................................................................................................................................................... 20
Analog input/output calibration ........................................................................................................................ 21
Digital input/output........................................................................................................................................... 21
Power ................................................................................................................................................................ 24
USB .................................................................................................................................................................. 25
EU Declaration of Conformity ............................................................................................................ 28
4
About this User's Guide
What you will learn from this user's guide
This user's guide describes the Measurement Computing USB-1808X data acquisition device and lists device
specifications.
Conventions in this user's guide
For more information
Text presented in a box signifies additional information and helpful hints related to the subject matter you are
reading.
Caution! Shaded caution statements present information to help you avoid injuring yourself and others,
damaging your hardware, or losing your data.
Bold text is used for the names of objects on a screen, such as buttons, text boxes, and checkboxes.
Italic text is used for the names of manuals and help topic titles, and to emphasize a word or phrase.
Preface
Where to find more information
Additional information about USB-1808X hardware is available on our website at www.mccdaq.com. You can
also contact Measurement Computing Corporation with specific questions.
Knowledgebase: kb.mccdaq.com
Tech support form: www.mccdaq.com/support/support_form.aspx
Email: techsupport@mccdaq.com
Phone: 508-946-5100 and follow the instructions for reaching Tech Support
For international customers, contact your local distributor. Refer to the International Distributors section on our
web site at www.mccdaq.com/International
.
5
Chapter 1
Introducing the USB-1808X
The USB-1808X is a multifunction data acquisition device providing the following features:
Eight 18-bit simultaneous-sampling differential (DIFF) or single-ended (SE) analog input channels –
software-selectable per channel as DIFF or SE
Sample rate of 200 kS/s per channel maximum
Analog input ranges of ±10 V, ±5 V, 0 V to 10 V, and 0 V to 5 V – software-selectable per channel
Two 16-bit analog outputs
Four individually-configurable digital I/O channels
Two high-speed general-purpose counters
Two quadrature encoder inputs
Two timer outputs
One external digital trigger for data acquisition and one external digital trigger for data generation
Two external clock inputs and two clock outputs for synchronous input and output operations with more
than one device.
Screw terminals for field wiring connections
The device is powered by the +5 V USB supply from the computer, requiring no external power.
The USB-1808X is a USB 2.0 high-speed device that is fully compatible with both USB 1.1, USB 2.0, and
USB 3.0 ports.
Functional block diagram
USB-1808X functions are illustrated in the block diagram shown here.
Figure 1. Functional block diagram
6
Chapter 2
Installing the USB-1808X
Unpacking
As with any electronic device, you should take care while handling to avoid damage from static
electricity. Before removing the device from its packaging, ground yourself using a wrist strap or by simply
touching the computer chassis or other grounded object to eliminate any stored static charge.
Contact us immediately if any components are missing or damaged.
Installing the software
Refer to the MCC DAQ Quick Start and the USB-1808X product page on our website for information about the
software supported by the USB-1808X.
Install the software before you install your device
The driver needed to run the USB-1808X is installed with the software. Therefore, you need to install the
software package you plan to use before you install the hardware.
Installing the hardware
To connect the USB-1808X to your system, connect the USB cable to an available USB port on the computer or
to an external USB hub connected to the computer. Connect the other end of the USB cable to the USB
connector on the device. No external power is required.
When connected for the first time, a
device. When the dialog closes, the installation is complete. The
the device is successfully installed.
If the Status LED turns off
If communication is lost between the device and the computer, the device LED turns off. To restore
communication, disconnect the USB cable from the computer and then reconnect it. This should restore
communication, and the LED should turn on.
Found New Hardware dialog opens when the operating system detects the
Status LED on the USB-1808X turns on after
Calibrating the hardware
The Measurement Computing Manufacturing Test department performs the initial factory calibration. Return
the device to Measurement Computing Corporation when calibration is required. The recommended calibration
interval is one year.
Updating firmware
Your DAQ device contains firmware that can be updated in the field if required. Firmware is available for
download at www.mccdaq.com/firmware.aspx
if an update to your device firmware is available.
. MCC recommends that you check this page periodically to see
7
Functional Details
External components
The USB-1808X has the following external components (see Figure 2 through Figure 4 on pgs. 9-10):
USB connector
LEDs
Screw terminals
USB connector
The USB connector provides +5 V power and communication. No external power supply is required.
Screw terminals
The screw terminals provide the following connections:
Chapter 3
Eight DIFF analog inputs (
Refer to Figure 2 and Figure 3 on page 9 for DIFF and SE pinouts.
Two analog outputs (
Four digital I/O lines (
Two general-purpose counter inputs (
Two quadrature encoder inputs (
Two timer outputs (
An external trigger input (
Two external clock inputs (
One +5 V power output (
Ten analog ground (
Use 16 AWG to 30 AWG wire when making connections to the screw terminals.
CH0H/CH0L to CH7H/CH7L) or eight SE analog inputs (CH0H to CH7H)
AOUT0 and AOUT1)
DIO0 to DIO3)
CTR0 and CTR1)
ENC0A, ENC0B, ENC0Z and ENC1A, ENC1B, ENC1Z)
TMR0 and TMR1)
ITRIG) and an external trigger output OTRIG)
ICLKI and OCLKI) and two external clock outputs (ICLKO, OCLKO)
+VO) connection
AGND) and seven digital ground (GND) connections
8
USB-1808X User's Guide Functional Details
Figure 2. DIFF mode pinout
Figure 3. SE mode pinout
9
USB-1808X User's Guide Functional Details
1
USB connector
3
Activity LED
2
Status LED
0
CH0H/CH0L (DIFF)
±10 V
1
CH2H/AGND (SE)
±5 V
2
CH3H/AGND (SE)
0 V to 5 V
3
CH6H/CH6L (DIFF)
0 V to 10 V
4
CH7H/CH7L (DIFF)
±5 V
LEDs
The USB-1808X has two LED indicators that indicate the status of power and data. The LEDs are stacked one
above the other, as shown in Figure 4.
The
The
Status LED turns on when the device is detected by the computer.
Activity LED blinks when data is transferred and is off otherwise.
Figure 4. LED indicators
Analog input
You can configure each analog input channel for either SE or DIFF mode. MCC recommends connecting
unused analog input terminals to analog ground terminals during operation. For example, if you are not using
CH7L, connect this terminal to an available AGND terminal.
The input voltage range is software-selectable per channel for ±10 V, ±5 V, 0 V to 10 V, or 0 V to 5 V.
Analog input operations can be paced by the internal clock or by an external clock (
ICLKI – refer to Clock I/O
on page 15). They can be initiated by a digital trigger (Digital triggering on page 15) or a pattern trigger
(Pattern triggering on page 15).
Refer to Synchronous I/O – mixing analog, digital, and counter scanning on page 15 for information on running
analog input scans at the same time as other subsystem scans.
For more information about analog signal connections
For more information about analog input connections, refer to the Guide to DAQ Signal Connections (available
for download at www.mccdaq.com/support/DAQ-Signal-Connections.aspx).
Channel-Gain queue
The channel-gain queue feature allows you to configure a different gain setting for each channel. The gain
settings are stored in a channel-gain queue list that is written to local memory on the device.
The channel-gain queue list can contain up to eight unique elements. The channel list must be in increasing
order. An example of a five-element list is shown in the following table.
Sample channel-gain queue list
Element Channel Range
10
USB-1808X User's Guide Functional Details
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.
Analog output
The two 16-bit analog outputs (AOUT0 and AOUT1) can be updated simultaneously at a rate of 500 kS/s per
channel. Each 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 at power up, or when a reset command is issued to the device.
Analog output operations can be paced by the internal clock or by an external clock (
on page 15). They can be initiated by a digital trigger (Digital triggering on page 15) or a pattern trigger
(Pattern triggering on page 15).
Refer to Synchronous I/O – mixing analog, digital, and counter scanning on page 15 for information on running
analog output scans at the same time as other subsystem scans.
OCLKI – refer to Clock I/O
Digital I/O
You can connect up to four digital I/O lines to DIO0 through DIO3. Each digital channel is individually
configurable for input or output. During initial power on or reset, the digital pins are set for input.
The digital I/O terminals can detect the state of any TTL-level input. Refer to the schematic shown in Figure 5.
Figure 5. Schematic showing switch detection by digital channel DIO0
If you set the switch to the +5 V input, DIO0 reads TRUE (1). When set to GND, DIO0 reads FALSE (0).
Digital input scanning
Digital input operations can be paced by the internal clock or by an external clock (ICLKI – refer to Clock I/O
on page 15). They can be initiated by a digital trigger (Digital triggering on page 15) or a pattern trigger
(Pattern triggering on page 15).
If no analog inputs are being scanned, the digital inputs can sustain rates up to 200 kHz. Digital input ports can
also be read asynchronously before, during, or after an analog input scan.
Refer to Synchronous I/O – mixing analog, digital, and counter scanning on page 15 for information on running
digital input scans at the same time as other subsystem scans.
Pull-up/down configuration
All digital I/O lines are pulled down to 0 V (LO) with a 47 kΩ resistor (default). You can change the
pull-up/down configuration using the internal jumper labeled
access the jumper on the circuit board.
To set the jumper for pull-up or pull-down, complete the following steps.
1. Unplug the device from the computer.
2. Turn the device over and rest the top of the housing on a flat, stable surface.
Caution! The discharge of static electricity can damage some electronic components. Before removing the
USB-1808X from its housing, ground yourself using a wrist strap or touch the computer chassis or
other grounded object to eliminate any stored static charge.
3. Remove the rubber fee from the bottom of the device, and the four screws using a #1 Philips head
screwdriver.
11
DIO. You must remove the device housing to
USB-1808X User's Guide Functional Details
4. Hold both the top and bottom sections together, turn the device over and rest it on the surface, then
carefully remove the top section of the case to expose the circuit board.
Figure 6 shows the location of the
DIO jumper on the circuit board.
Figure 6. Pull-up/down jumper location
5.Configure the DIO jumper for pull-up or pull-down, as shown in Figure 7.
Figure 7. Pull-up/down jumper configuration
6.Replace the top section of the housing and fasten it to the bottom section with the four screws.
For more information about digital signal connections
For general information about digital signal connections and digital I/O techniques, refer to the Guide to DAQ
Signal Connections (available for download at www.mccdaq.com/support/DAQ-Signal-Connections.aspx).
Counter input
Counter inputs can be read asynchronously under program control, or synchronously as part of a digital scan
group.
CTR0 and CTR1 terminals are 32-bit general-purpose counters that can accept frequency inputs up to
The
50 MHz.
The USB-1808X supports the following counter input modes:
Totalize
Period measurement
Pulse-width measurement
Counter input modes are programmable with software. Each mode supports additional counter operation
options.
12
USB-1808X User's Guide Functional Details
Clear on read
The counter is cleared after each read (synchronous or asynchronous). The value of the counter
before it was cleared is latched and returned.
Range limit
When counting up: The counter rolls over to MINLIMIT (or stops if Non-recycle is set) when the
(or stops if Non-recycle is set).
Non-recycle
The counter stops if a count overflow or underflow occurs (or, if Range limit is set, the MAXLIMIT
or MINLIMIT value is reached). Counting resumes if direction is reversed or the counter is reloaded.
Typically, when data is acquired with no counter operation options set, the count of each counter channel is set
to 0 and latched at the beginning of the acquisition.
When counter options are set the counters can concurrently monitor time periods, frequencies, pulses, and other
event-driven incremental occurrences directly from pulse-generators, limit switches, proximity switches, and
magnetic pick-ups.
Counter input operations can be paced by the internal clock or by an external clock (
ICLKI – refer to Clock I/O
on page 15). They can be initiated by a digital trigger (Digital triggering on page 15) or a pattern trigger
(Pattern triggering on page 15).
Refer to Synchronous I/O – mixing analog, digital, and counter scanning on page 15 for information on running
counter input scans at the same time as other subsystem scans.
Totalize counter mode
The USB-1808X can be used as a high-speed pulse counter for general counting applications. The internal
counter increments when the TTL levels transition from low to high or from high to low.
Each option supported in Totalize mode is explained in following table:
Totalize counter mode options
Counter option Description
maximum count (specified by the MAXLIMIT value) is reached.
When counting down: The counter counts down to MINLIMIT and then rolls over to MAXLIMIT
Period measurement mode
Use period mode to measure the period of a signal at a counter channel's input. You can measure x1, x10, x100
or x1000 periods for 32-bit values. Four resolutions are available — 20 ns, 200 ns, 2000 ns, or 20,000 ns. All
period measurement mode options are software-selectable. The 100 MHz system clock is used as the timing
source. Periods from sub-microsecond to many seconds can be measured.
Pulse width measurement mode
Use pulse width mode to measure the time from the rising edge to the falling edge, or vice versa, on a counter
input signal. Four resolutions are available — 20 ns, 200 ns, 2000 ns, or 20,000 ns. All pulse width
measurement mode options are software selectable. The 100 MHz system clock is used as the timing source.
Pulse widths from sub-microsecond to many seconds can be measured.
Quadrature encoder input
The USB-1808X can simultaneously decode signals from up to two encoders. Quadrature encoders, 50 MHz
maximum pulse frequency, and X1, X2, and X4 count modes are supported.
The USB-1808X provides A, B, and Z inputs – ENCxA, ENCxB, and ENCxZ – for each connected encoder.
A typical encoder generates the A and B signals at a 90° phase shift with respect to each other. These signals are
used to determine system position (counts), velocity (counts per second), and direction of travel or rotation. The
Z signal can be programmed to latch the current count or reload the counter with the MINLIMIT value
(counting up) or the MAXLIMIT value (counting down).
The Z signal may be used to establish an absolute reference position within one count of the encoder travel or
rotation. This signal can be used to reload the position counter, which is useful at system startup when the
incremental encoder cannot determine the starting position.
13
USB-1808X User's Guide Functional Details
Count mode
Select X1, X2, or X4. Count modes provide different levels of accuracy with respect to the encoder
X4: count rising and falling edges on both inputs A and B.
Range limit
When counting up: The counter stops when the maximum count (specified by the MAXLIMIT
value) is reached. Counting resumes if direction is reversed or the counter is cleared.
Clear on Z
The counter is cleared by the Z signal.
Latching
Latching mode allows the count to be latched by the Z signal.
Encoder input operations can be paced by the internal clock or by an external clock (ICLKI – refer to Clock I/O
on page 15). They can be initiated by a digital trigger (Digital triggering on page 15) or a pattern trigger
(Pattern triggering on page 15).
Refer to Synchronous I/O – mixing analog, digital, and counter scanning on page 15 for information on running
quadrature encoder scans at the same time as other subsystem scans.
Each supported quadrature encoder option is explained in following table:
Quadrature encoder options
Encoder
option
Description
position.
X1: counts rising edges on input A.
X2: counts rising edges and falling edges on input A.
value) is reached. Counting resumes if direction is reversed or the counter is cleared.
When counting down: The counter stops when the minimum count (specified by the MINLIMIT
Quadrature encoder options that are specific to the Z signal (ENCxZ) are is explained in following table.
Z input quadrature encoder options ()
Counter mode Description
Timer output
You can use TMR0 through TMR1 as 32-bit timer outputs. Each timer can generate pulse rates of up to 50 MHz,
with programmable pulse widths down to 10 ns.
The timer output rate and pulse width can be updated asynchronously at any time, however, doing so results in a
pulse stream that is not seamless.
The following timer output options are software-selectable:
pulse frequency
duty cycle (pulse width divided by the pulse period)
number of pulses to generate
time delay before starting the timer output after it is enabled
idle state of the output (idle high or idle low)
The time delay can range from 0 seconds to 42.94 seconds.
Figure 8. USB-1808X PWM timer channel
Timer output operations can be paced by the internal clock or by an external clock (OCLKI – refer to Clock I/O
on page 15). They can be initiated by a digital trigger (Digital triggering on page 15).
14
USB-1808X User's Guide Functional Details
Synchronous I/O – mixing analog, digital, and counter scanning
The USB-1808X can read analog, digital, and counter inputs, and generate up to two analog outputs and one
digital pattern output at the same time. Digital and counter inputs do not affect the overall A/D rate because
these inputs use no time slot in the scanning sequencer.
For example, one analog input channel can be scanned at the full 200 kS/s A/D rate along with digital and
counter input channels. Each analog channel can have a different gain, and counter and digital channels do not
need additional scanning bandwidth if there is at least one analog channel in the scan group. Digital input
channel sampling is done during the dead time of the scan period when no analog sampling is being done.
Clock I/O
The USB-1808X provides one external clock input (ICLKI) and one clock output (ICLKO) for input operations.
Connect an external clock signal to
The pacer clock is available at
The USB-1808X provides one external clock input (
operations.
Connect an external clock signal to
The pacer clock is available at
ICLKI.
ICLKO.
OCLKI) and one clock output (OCLKO) for output
OCLKI.
OCLKO.
Digital triggering
The ITRIG (for triggering input operations) and OTRIG (for triggering output operations) terminals are external
digital trigger inputs. The trigger mode is software-selectable for edge or level sensitive. Edge sensitive mode is
selectable for rising or falling. Level sensitive mode is selectable for high or low.
Pattern triggering
You can also start an input or output scan with a digital pattern trigger using DIO0 – DIO3. The pattern
represents the state of up to four bits on the port.
You specify the pattern and the trigger type with software. Supported trigger types are Above Pattern, Below
Pattern, Equal Pattern, and Not Equal Pattern. The scan begins when the trigger conditions are met.
The base clock is fixed at 100 MHz (10 ns). The trigger pattern must be held for five base clock cycles (50 ns)
to ensure that it is properly detected. The trigger latency is 1 scan clock period + 8 base clock cycles (80 ns).
Mask option
Use a bitmask to specify which bits to include or exclude from the pattern to detect. To include a bit in the
pattern, sets its value to 1. To exclude a bit from the pattern, sets its value to 0. Refer to the pattern and mask
values shown in Figure 9 and Figure 10.
In Figure 9 all mask bits are set to 1, so all the bits are included in the pattern to detect.
Figure 9. Trigger mask with all bits included
15
USB-1808X User's Guide Functional Details
In Figure 10 all mask bits are excluded except bit 3. The result of this operation is that only bit 3 is included in
the pattern to detect.
Figure 10. Trigger mask with some bits excluded
Ground
The analog ground (AGND) terminals provide a common ground for all analog channels.
The digital ground (
terminals.
GND) terminals provide a common ground for the digital, trigger, counter, and encoder
Power output
The +VO terminal can output up to 10 mA maximum. You can use this terminal to supply power to external
devices or circuitry.
16
USB-1808X User's Guide Functional Details
Mechanical drawings
Figure 11. USB-1808X circuit board (top) and enclosure dimensions
17
A/D converter type
Simultaneous
ADC resolution
18 bits
Number of channels
8 differential (DIFF), 8 single-ended (SE);
software-selectable per-channel for SE or DIFF
Input voltage range
±10 V, ±5 V, 0 V to 10 V, 0 V to 5 V
Software-selectable per channel
All specifications are subject to change without notice.
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.
Analog input
Table 1. General analog input specifications
Parameter Condition Specification
Chapter 4
Input bandwidth All input ranges, small signal
Common mode voltage
range
Channel gain queue Up to 8 elements Software-selectable. Queue list may contain up to
±10 V range
DC to 100 kHz
2.0 MHz
±10.1 V
Digital pattern detection (see Pattern trigger on
eight elements of unique, consecutive channels
paired with any valid range.
18
USB-1808X User's Guide Specifications
±10 V
0.020
1.5
0.00076
3.576
0.00023
4
±5 V
0.020
1.0
0.00057
2.028
0.00023
4
0 V to 10 V
0.020
1.5
0.00028
3.528
0.00023
4
0 V to 5 V
0.020
1.0
0.00014
2.007
0.00023
4
Signal-to-noise ratio (SNR)
94 dB
Signal-to-noise-and-distortion ratio
(SINAD)
94 dB
Total harmonic distortion (THD)
–108 dB
Spurious free dynamic range (SFDR)
112 dB
Effective number of bits (ENOB)
15.3 bits
SNR
91 dB
SINAD
91 dB
THD
–105 dB
SFDR
107 dB
ENOB
14.8 bits
SNR
87 dB
SINAD
87 dB
THD
–104 dB
SFDR
109 dB
ENOB
14.5 bits
SNR 83 dB
SINAD
83 dB
THD
–103 dB
SFDR
103 dB
ENOB
13.6 bits
±10 V
11.6
1.77
±5 V
18.0
2.73
0 V to 10 V
23.3
3.54
0 V to 5 V
36.1
5.47
Accuracy
Analog input DC voltage measurement accuracy
Table 2. DC accuracy components and specifications. All values are (±)
Range
Gain error
(% of
reading)
Offset
error
(mV)
INL error
(% of
range)
Absolute
accuracy at
Full Scale
(mV)
Gain
temperature
coefficient
(% reading/°C)
Dynamic performance
Table 3. Dynamic performance specifications
Range Condition Specification
±10 V
±5 V
Offset
temperature
coefficient
(µV/°C)
0 V to 10 V
0 V to 5 V
Noise performance
For the peak-to-peak noise distribution test, a differential input channel is connected to AGND at the input
terminal block, and 32,000 samples are acquired at the maximum rate available at each setting.
Table 4. Noise performance specifications
Range Counts LSBrms
19
USB-1808X User's Guide Specifications
Number of channels
2 Resolution
16 bits
Output ranges
Calibrated
±10 V
Output transient
Host computer is reset, powered on,
to the device
Duration: 5 ms
Differential non-linearity
±0.25 LSB typ
±1 LSB max
Output current
AOUTx pins
±3.5 mA max
Output short-circuit protection
Single AOUTx channel connected to
AGND
Unlimited duration
Output coupling
DC
Power on and reset state
DACs cleared to zero-scale: 0 V, ±50 mV
Output noise
100 µVrms
trigger on page 24)
output scan clock (OCLKI pin)
Output update rate
0.023 Hz to 500 kHz per channel
Slew rate
15 V/µS
Hardware paced
1,000 kS/s max, system-dependent
±10 V
16
±10 V
0.0183
1.831
4.7
9.4
±10 V
1.0
Analog output
Table 5. Analog output specifications
Parameter Condition Specification
suspended, or a reset command is issued
Powered off from 0 V output Duration: 20 ms
Trigger source OTRIG (see External trigger on page
Scan clock source Internal output scan clock or external
Throughput Software paced 33 S/s to 8,000 S/s typ, system-dependent
ITRIG for inputs, OTRIG for outputs (see External trigger on page 24)
Digital pattern detection for inputs and outputs (see Pattern trigger on page 24)
Input high voltage
2.0 V min
5.5 V absolute max
Input low voltage
0.8 V max
0 V recommended min
3.76 V min (IOH = –2.5 mA)
Output low voltage
0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 2.5 mA)
Output current
±2.5 mA max
Analog input/output calibration
Table 9. Analog I/O calibration specifications
Parameter Specification
Digital input/output
Table 10. Digital I/O specifications
Parameter Specification
Pull-up configuration The port has 47 kΩ resistors configurable as pull-up or pull-down (default) via internal
Digital I/O transfer rate
Output high voltage 4.4 V min (IOH = –50 µA)
33 to 8,000 port reads/writes or single bit reads/writes per second typ,
–0.5 V absolute min
21
USB-1808X User's Guide Specifications
Terminal names
CTR0, CTR1
Number of channels
2 channels
Resolution
32-bit
Counter type
FPGA
Counter input modes
Totalize, Pulse width, Period
Input type
Schmitt trigger, 33 Ω series resistor, 47kΩ pull-down to ground
Note 3: This is the total quiescent current requirement for the device that includes up to 10 mA for the status LED. This
does not include any potential loading of the digital I/O bits, +VO terminal, or the AOUTx outputs.
Note 4: The +4.5 V min limit includes the +VO 10 mA load, it does not include any potential loading of the digital I/O
bits or the AOUTx outputs.
24
USB-1808X User's Guide Specifications
USB device type
USB 2.0 (high-speed)
Device compatibility
USB 1.1, USB 2.0, USB 3.0
USB cable type
A-B cable, UL type AWM 2725 or equivalent. (Min 24 AWG VBUS/GND,
min 28 AWG D+/D–)
USB cable length
3 m (9.84 ft) max
Operating temperature range
0 °C to 55 °C max
Storage temperature range
–40 °C to 85 °C max
Humidity
0% to 90% non-condensing max
User connection length
3 m (9.84 ft) max
Connector type
Screw terminal
Wire gauge range
16 AWG to 30 AWG
USB
Table 19. USB specifications
Parameter Specification
Environmental
Table 20. Environmental specifications
Parameter Specification
Mechanical
Table 21. Mechanical specifications
Parameter Specification
Dimensions (L × W × H) 127 × 89.9 × 35.6 mm (5.00 × 3.53 × 1.40 in.)
Screw terminal connector
Table 22. Screw terminal connector specifications
Parameter Specification
25
USB-1808X User's Guide Specifications
#
Label
Use # Label
Use 1 CH0H
AI channel 0 HI
29
CH7L
AI channel 7 LO
3
AGND
Analog ground
31
AGND
Analog ground
5
CH1L
AI channel 1 LO
33
CH6H
AI channel 6 HI
6
AGND
Analog ground
34
AGND
Analog ground
7
CH2H
AI channel 2 HI
35
CH5L
AI channel 5 LO
8
CH2L
AI channel 2 LO
36
CH5H
AI channel 5 HI
9
AGND
Analog ground
37
AGND
Analog ground
10
CH3H
AI channel 3 HI
38
CH4L
AI channel 4 LO
11
CH3L
AI channel 3 LO
39
CH4H
AI channel 4 HI
12
AGND
Analog ground
40
AGND
Analog ground
14
AGND
Analog ground
42
AOUT1
AO channel 1
15
GND
Digital Ground
43
AGND
Analog ground
16
TMR0
Timer 0 output
44
GND
Digital Ground
17
TMR1
Timer 1 output
45
DIO0
DIO channel 0
18
ICLKO
Input scan clock output
46
DIO1
DIO channel 1
19
OCLKO
Output scan clock output
47
GND
Digital Ground
20
GND
Digital ground
48
DIO2
DIO channel 2
21
ICLKI
Input scan clock input
49
DIO3
DIO channel 3
22
OCLKI
Output scan clock input
50
GND
Digital Ground
23
ITRIG
Input Trigger
51
CTR0
Counter 0 input
25
GND
Digital ground
53
GND
Digital ground
26
ENC1A
Encoder 1 Input A
54
ENC0A
Encoder 0 Input A
27
ENC1B
Encoder 1 Input B
55
ENC0B
Encoder 0 Input B
28
ENC1Z
Encoder 1 Input Z
56
ENC0Z
Encoder 0 Input Z
Differential mode pinout
Table 23. 8-channel differential mode pinout
Terminal Terminal
2 CH0L AI channel 0 LO 30 CH7H AI channel 7 HI
4 CH1H AI channel 1 HI 32 CH6L AI channel 6 LO
13 +VO +5V power output 41 AOUT0 AO channel 0
24 OTRIG Output Trigger 52 CTR1 Counter 1 input
26
USB-1808X User's Guide Specifications
#
Label
Use # Label
Use 1 CH0H
AI channel 0 HI
29
NC
No connection
3
AGND
Analog ground
31
AGND
Analog ground
5
NC
No connection
33
CH6H
AI channel 6 HI
6
AGND
Analog ground
34
AGND
Analog ground
7
CH2H
AI channel 2 HI
35
NC
No connection
8
NC
No connection
36
CH5H
AI channel 5 HI
9
AGND
Analog ground
37
AGND
Analog ground
10
CH3H
AI channel 3 HI
38
NC
No connection
11
NC
No connection
39
CH4H
AI channel 4 HI
12
AGND
Analog ground
40
AGND
Analog ground
14
AGND
Analog ground
42
AOUT1
AO channel 1
15
GND
Digital Ground
43
AGND
Analog ground
16
TMR0
Timer 0 output
44
GND
Digital Ground
17
TMR1
Timer 1 output
45
DIO0
DIO channel 0
18
ICLKO
Input scan clock output
46
DIO1
DIO channel 1
19
OCLKO
Output scan clock output
47
GND
Digital Ground
20
GND
Digital ground
48
DIO2
DIO channel 2
21
ICLKI
Input scan clock input
49
DIO3
DIO channel 3
22
OCLKI
Output scan clock input
50
GND
Digital Ground
23
ITRIG
Input Trigger
51
CTR0
Counter 0 input
25
GND
Digital ground
53
GND
Digital ground
26
ENC1A
Encoder 1 Input A
54
ENC0A
Encoder 0 Input A
27
ENC1B
Encoder 1 Input B
55
ENC0B
Encoder 0 Input B
28
ENC1Z
Encoder 1 Input Z
56
ENC0Z
Encoder 0 Input Z
Single-ended mode pinout
Table 24. 16-channel single-ended mode pinout
Terminal Terminal
2 NC No connection 30 CH7H AI channel 7 HI
4 CH1H AI channel 1 HI 32 NC No connection
13 +VO +5V power output 41 AOUT0 AO channel 0
24 OTRIG Output Trigger 52 CTR1 Counter 1 input
27
EU Declaration of Conformity
According to ISO/IEC 17050-1:2010
Manufacturer: Measurement Computing Corporation
Address: 10 Commerce Way
Norton, MA 02766
USA
Product Category: Electrical equipment for measurement, control and laboratory use.
Date and Place of Issue: March 23, 2017, Norton, Massachusetts USA
Test Report Number: EMI6990.17
Measurement Computing Corporation declares under sole responsibility that the product
USB-1808X
is in conformity with the relevant Union Harmonization Legislation and complies with the essential
requirements of the following applicable European Directives:
Conformity is assessed in accordance to the following standards:
EMC:
Emissions:
EN 61326-1:2013 (IEC 61326-1:2012), Class A
EN 55011: 2009 + A1:2010 (IEC CISPR 11:2009 + A1:2010), Group 1, Class A
Immunity:
EN 61326-1:2013 (IEC 61326-1:2012), Controlled EM Environments
EN 61000-4-2:2008 (IEC 61000-4-2:2008)
EN 61000-4-3 :2010 (IEC61000-4-3:2010)
Safety:
EN 61010-1 (IEC 61010-1)
Environmental Affairs:
Articles manufactured on or after the Date of Issue of this Declaration of Conformity do not contain any of the
restricted substances in concentrations/applications not permitted by the RoHS Directive.