USB-1808 Series
High-Speed, High-Precision, Simultaneous USB Devices
Features• Eight 18-bit differential(DIFF) or single-ended (SE)analog inputs• Simultaneous sampling (up to
200 kS/s per channel)• Two analog outputs• Four digital I/O• Two general-purpose counters
and two quadrature encoders• Two timer outputs• Synchronous AI, AO, DIO
operations (up to 200 kS/s perchannelUSB-1808 Series devices provide eight simultaneously-sampling analog inputs that are configurable per channel as differential or single-ended, two analog outputs, four digital I/O, twogeneral-purpose counters, two quadrature encoders, and two timer outputs.

• External clock I/O, external
digital triggering, and pattern
triggering

Overview
USB-1808 Series devices are high-performance, simultaneous-sampling DAQ
devices. All devices provide synchronous and concurrent voltage I/O, waveform
output, counter input, quadrature encoder input, timer output, and digital I/O.

• Board-only OEM available

Supported Operating Systems• Windows® 11/10/8/7/Vista®/

USB-1808X models offer synchronous I/O operations at rates up to 200 kS/s perchannel, while USB-1808 models offer the same features at rates up to 50 kS/s
per channel.

XP 32/64-bit• Linux®

Analog Output

Channel-Gain Queue

Analog Input
USB-1808 Series devices provide eight,
18-bit simultaneous-sampling analog
inputs that are software-selectable perchannel for DIFF or SE mode.
USB-1808X models support sample
rates up to 200 kS/s per channel, whileUSB-1808 models support sample rates
up to 50 kS/s per channel. All devices
support voltage ranges of ±10 V, ±5 V,
0 V to 10 V, and 0 V to 5 V.

Use the channel-gain queue feature toconfigure a list of channels and gains
for each scan. Each channel can have a
different gain setting, and the settings
are stored in a list that is written to local
memory on the device.

USB-1808 Series devices offer two 16-bit
analog outputs. USB-1808X models can be
updated at a rate of 500 kS/s per channel,
while USB-1808 models can be updated
at a rate of 125 kS/s. The output range isfixed at ±10 V.

The channel-gain queue list on
USB-1808 Series devices can contain up
to eight unique channels that must be
listed in increasing order.

Digital I/O
Four digital I/O lines are individuallyconfigurable for input or output. The
DIO terminals can detect the state of any
TTL-level input. Users can configure forpull-up (+5 V) or pull-down (0 V) with an
onboard jumper.

USB-1808 Series Selection Chart
Model

AnalogInputsSample Rate(max/channel)

AnalogOutputs

Update Rate(max/channel)

DigitalI/OCounter
InputsEncoder
InputsTimer
Outputs

Signal I/O

USB-1808

8 DIFF/8 SE

50 kS/s2

125 kS/s

4

2

2

2

Screw Terminal

USB-1808X

8 DIFF/8 SE

200 kS/s

2

500 kS/s

4

2

2

2

Screw Terminal

USB-1808-OEM

8 DIFF/8 SE

50 kS/s2

125 kS/s

4

2

2

2

HeaderUSB-1808X-OEM

8 DIFF/8 SE

200 kS/s

2

500 kS/s

4

2

2

2

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USB-1808 Series
Features
Counter Input

Each analog channel can have a different gain, and digital,counter, and encoder channels do not need additional scanning bandwidth as long as there is at least one analog channel
in the scan group.

USB-1808 Series devices have two 32-bit general-purpose counter
inputs that can be read asynchronously under program control,or synchronously as part of a digital scan group.

Digital input channel sampling is done during the dead time ofthe scan period when no analog sampling is being done.

Each counter can accept frequency inputs up to 50 MHz andsupports the following software-selectable counter input modes:•

Totalize – 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.

•

Period measurement – Measure the period of a signal at acounter channel input. Users 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•

Pulse-width measurement – Measure the time from therising edge to the falling edge, or vice versa, on a signal ona counter input. Four resolutions are available — 20 ns,
200 ns, 2000 ns, or 20,000 ns.

Clock I/O
USB-1808 Series devices provides two external clock inputs –one for pacing input scan and the other to pace output scans.
These devices also include two clock outputs – one to output theinternal or external clock used for input scans, and the otherto output the internal or external clock used for output scans.

TriggeringUSB-1808 Series devices support digital triggering and pattern
triggering.

Each mode supports additional counter options. When counteroptions 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.

The ITRIG and OTRIG pins are used for external TTL-level triggering – ITRIG can trigger input scans, and OTRIG can trigger
output scans. The trigger mode is software-selectable for edge orlevel sensitive, rising or falling edge, high or low level.
USB-1808 Series devices can also start an input or output scanwith a digital pattern trigger using any of the four DIO ports. A
scan is triggered when a specified pattern is detected. Specificbits can be masked or ignored. A digital pattern can be input or
output under the timing control of a clock signal.

Quadrature Encoder Input
USB-1808 Series devices can simultaneously decode signals
from up to two quadrature encoders. Encoders with a 50 MHz
maximum pulse frequency and X1, X2, and X4 count modes
are supported.

Calibration

Each device provides A, B, and Z inputs for each connectedencoder. A typical encoder generates the A and B signals at a 90°
phase shift with respect to each other. These signals are used todetermine system position (counts), velocity (counts per second),
and direction of travel or rotation.

The USB-1808 Series devices are factory-calibrated using a NISTtraceable calibration process. Specifications are guaranteed for
one year. For calibration beyond one year, return the device tothe factory for recalibration.

USB-1808 Series OEM Versions

Timer Output

OEM versions have board-only form factors with header connectors for OEM and embedded applications (no case, CD, or
USB cable included). All devices can be further customized tomeet customer needs.

Two timers can generate pulse rates of up to 50 MHz each, 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.
Timer output operations can be paced by the internal clock orby an external clock, and can be initiated by a digital trigger.

Synchronous I/O – Mixing Analog,
Digital, and Counter ScanningUSB-1808 Series devices can read analog, digital, counter , andencoder inputs, and generate up to two analog outputs and one
digital pattern output at the same time. Digital, counter, andencoder inputs do not affect the overall A/D rate because these
inputs use no time slot in the scanning sequencer.

The OEM versions have the same specifications as the standard
devices, but come in a board-only form factor with header connectors
instead of screw terminals.

For example, one analog input channel can be scanned at the
maximum A/D rate along with digital, counter, and encoder
input channels.
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USB-1808 Series
Software
Software Support
USB-1808 Series devices are supported by the software in the table below.
Ready-to-Run Applications
Data acquisition companion software with drag-and-drop interface that is used to acquire,view, and log data, and generate signals. DAQami can be configured to log analog, digital, andcounter channels, and to view that data in real-time or post-acquisition on user-configurable
displays. Logged data can be exported for use in Excel® or MATLAB®. Windows OS

DAQami™

DAQami is included with the free MCC DAQ Software bundle.

An interactive installation, configuration, and test utility for MCC hardware. Windows OS

InstaCal™

InstaCal is included with the free MCC DAQ Software bundle.

TracerDAQ™ andTracerDAQ Pro

Virtual strip chart, oscilloscope, function generator, and rate generator applications used togenerate, acquire, analyze, display, and export data. Supported features may vary by hardware.
The Pro version provides enhanced features. Windows OS
TracerDAQ is included with the free MCC DAQ Software bundle.
TracerDAQ Pro is available as a purchased software download.

General-Purpose Programming Support
Universal Library™
(UL) for Windows

Library for developing applications in C, C++, VB, C# .Net, VB .Net, and Python on Windows.
The UL for Windows is included with the free MCC DAQ Software bundle.
The UL Python API for Windows is available on GitHub (https://github.com/mccdaq/mcculw).

Library for developing applications in C, C++, and Python on Linux.
UL for Linux®

UL for Linux is available on GitHub (https://github.com/mccdaq/uldaq).
Open-source, third-party Linux drivers are also available for supported MCC devices.

Application-Specific Programming Support
ULx forNI LabVIEW™

DASYLab®

Measurement Computing

A comprehensive library of VIs and example programs for NI LabVIEW that is used to develop
custom applications that interact with most MCC devices. Windows OS
ULx for NI LabVIEW is included with the free MCC DAQ Software bundle.
Icon-based data acquisition, graphics, control, and analysis software that allows users to create
complex applications in minimal time without text-based programming. Windows OS
DASYLab is available as a purchased software download. An evaluation version is available for28 days.

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USB-1808 SeriesSpecifications

Signal I/O Connector

818-bit18 bit18-bitADC
ADC

BufferBufferx2

Analog Output 2

4

Buffer16-bit16 bit16-bit
DAC
DAC

FPGA
FPGA

Trigger Input

2

Clock Input

2

Clock Output

2

Counter Input

2 Quad Counter Input

BitwiseBitwiseProgrammable
Programmable
DIO
DIO

DIO
DIO
Protection
Protection

2

Timer Output

2

Power
Power Supplies
Supplies
withwith Shutdown
Shutdown
andand Soft
Soft Start
Start

Microcontroller
Microcontroller withwithUSB
USB 2.0
2.0 High-Speed
High-Speed
Interface
Interface

EEPROM
EEPROM

Specifications

Signal I/O Connector

x8
Analog Input

USB
USB
Port
Port

24
24 MHzM
MHz
CrystalCrystalyCommon mode voltage range±10 V range: ±10.1 V±5 V range: ±10.1 V
0 V to 10 V range: ±10.1 V
0 V to 5 V range: ±10.1 V
Common mode rejection ratio (fIN ≤ 1 kHz, all input ranges): 90 dB
Crosstalk (±10 V, adjacent channels, DC to 100 kHz): –95 dB
Input coupling: DC
Sample rate
USB-1808: 0.023 Hz to 50 kHz; software-selectable
USB-1808X: 0.023 Hz to 200 kHz; software-selectable
Scan clock source: Internal input scan clock or external input scan clock (ICLKI pin)
Trigger source
ITRIG (see External Trigger on page 6)
Digital pattern detection (see Pattern Trigger on page 6)
Channel gain queue (up to 8 elements): Software-selectable. Queue list may
contain up to eight elements of unique, consecutive channels paired withany valid range.
Warm-up time: 15 minutes min

These specifications apply to both standard and OEM versions unless noted.
All specifications are subject to change without notice.
Typical for 25 °C unless otherwise specified.

Analog Input

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
Absolute max input voltage (CHx relative to AGND): ±25 V max (power on);
±15 V max (power off)
Input impedance: >1 GΩ (power on); 1000 Ω (power off)
Input bias current: ±50 pA
Input bandwidth, all input ranges, small signal (–3 dB): 2.0 MHz
Input capacitance: 50 pf

Analog Input DC Voltage Measurement Accuracy (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)

Offset Temperature
Coefficient(µV/°C)

±10 V

0.020

1.5

0.000763.576

0.00023

4

±5 V

0.020

1.0

0.00057

2.028

0.00023

40 V to 10 V

0.020

1.5

0.000283.528

0.00023

40 V to 5 V

0.020

1.0

0.000142.007

0.00023

4

Dynamic Performance±10 V range
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

Measurement Computing(508) 946-5100±5 V range
SNR: 91 dB
SINAD: 91 dB
THD: –105 dB
SFDR: 107 dB
ENOB: 14.8 bits

40 V to 10 V range
SNR: 87 dB
SINAD: 87 dB
THD: –104 dB
SFDR: 109 dB
ENOB: 14.5 bits

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0 V to 5 V range
SNR: 83 dB
SINAD: 83 dB
THD: –103 dB
SFDR: 103 dB
ENOB: 13.6 bits

mccdaq.com

USB-1808 SeriesSpecifications
Digital I/O transfer rate (synchronous)
USB-1808: 0.023 Hz to 50 kHz input, 125 kHz output, based on the internal
clock speed of 100 MHz
USB-1808X: 0.023 Hz to 200 kHz input, 500 kHz output, based on the internal
clock speed of 100 MHz
Scan clock source for input: Internal input scan clock or external input scanclock (ICLKI pin)
Scan clock source for input: Internal output scan clock or external output scanclock (OCLKI pin)
Trigger source
ITRIG for inputs, OTRIG for outputs (see External Trigger on page 6)
Digital pattern detection (see Pattern Trigger on page 6)
Input high voltage: 2.0 V min, 5.5 V absolute max
Input low voltage: 0.8 V max, –0.5 V absolute min, 0 V recommended min
Output high voltage: 4.4 V min (IOH = –50 µA), 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

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 acquiredat the maximum rate available at each setting.

Range

Counts

LSBrms

±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

Analog Output

Number of channels: 2
Resolution: 16 bits
Output ranges (calibrated): ±10 V
Output transient
Host computer is reset, powered on, suspended, or a reset command isissued to the device		Duration: 5 ms
		Amplitude: 2 V p-p
Powered off from 0 V output
		Duration: 20 ms
Amplitude: 5 V p-p
Differential nonlinearity: ±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 source
OTRIG (see External Trigger on page 6)
Digital pattern detection (see Pattern Trigger on page 6)
Scan clock source: Internal output scan clock or external output scan clock(OCLKI pin)
Output update rate
		USB-1808: 0.023 Hz to 125 kHz per channel
		USB-1808X: 0.023 Hz to 500 kHz per channel
Slew rate: 15 V/µS
Throughput
Software paced: 33 S/s to 8,000 S/s typ, system-dependent
Hardware paced
		USB-1808: 250 kS/s max, system-dependent
		USB-1808X: 1,000 kS/s max, system-dependent

Counter

Terminal names: CTR0, CTR1
Number of channels: 2 channels
Resolution: 32-bit
Counter type: FPGACounter input modes: Totalize, Pulse width, Period
Input type : Schmitt trigger, 33 Ω series resistor, 47 kΩ pull-down to ground
Input source: CTR0, CTR1
Scan clock source: Internal input scan clock or external input scan clock (ICLKI pin)
Trigger source
ITRIG (see External Trigger on page 6)
Digital pattern detection (see Pattern Trigger on page 6)Counter read clock: Internal or external input scan clock up to 200 kHz
Period/pulse width resolution: 20 ns, 200 ns, 2 µs or 20 µs; software-selectable
Input high voltage: 2.2 V min, 5.5 V max
Input low voltage: 1.5 V max, –0.5 V min
Schmitt trigger hysteresis: 0.4 V min, 1.2 V max
Input frequency: 50 MHz, max
Schmitt trigger hysteresis: 0.76 V typ, 0.4 V min, 1.2 V max
Input high voltage threshold: 1.74 V typ, 1.3 V min, 2.2 V max
Input low voltage threshold: 0.98 V typ, 0.6 V min, 1.5 V max
Input low voltage limit: –0.5 V absolute min, 0 V recommended min

Quadrature Inputs

Terminal names: ENC0A, ENC0B, ENC0Z; ENC1A, ENC1B, ENC1Z
Number of encoders: 2
Signals per encoder: A, B and Z
Resolution: 20 ns
Maximum frequency: 50 MHz
Minimum pulse width: 10 ns
De-bounce function: None
Scan clock source: Internal input scan clock or external input scan clock (ICLKI pin)
Trigger source
ITRIG (see External Trigger on page 6)
Digital pattern detection (see Pattern Trigger on page 6)
Input high voltage: 2.2 V min, 5.5 V max
Input low voltage: 1.5 V max, –0.5 V min
Absolute maximum input voltage: 5.5 V

Calibrated Absolute Accuracy±10 V range: ±16 LSB

Calibrated Absolute Accuracy Components
Range: ±10 V% of reading: 0.0183
Offset: ±1.831 mV
Offset tempco: ±4.7 µV/°C
Gain tempco: 9.4 ppm of range/°C

Timer

Relative Accuracy (±LSB)

Terminal name: TMR0, TMR1
Timer type: PWM output with count, period, delay, and pulse width registers
Output value: Default state is idle low with pulses high, software-selectable
output invert
Trigger source: OTRIG (see External Trigger on page 6)Internal clock frequency: 100 MHz
Register widths: 32-bit
High pulse width: 10 ns min
Low pulse width: 10 ns min
Output high voltage: 4.4 V min (IOH = –50 µA), 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±10 V range: 1.0 INL

Analog Input/Output Calibration

Warm-up time: 15 minutes recommended min
Calibration method: Factory calibration
Calibration interval: 1 year

Digital Input/Output

Digital type: CMOS
Number of I/O: 4
Configuration: Each bit may be configured as input (power on default) or output
Pull-up configuration: The port has 47 kΩ resistors configurable as pull-up or
pull-down (default) via internal jumper (DIO).
Digital I/O transfer rate (system paced, asynchronous): 33 to 8,000 port reads/
writes or single bit reads/writes per second typ, system dependent.

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USB-1808 Series
Ordering
MemoryExternal Clock Input/Output

Terminal names: ICLKI, ICLKO, OCLKI, OCLKO
Terminal types
xCLKI: Input, active on rising edge
xCLKO: Output, power on default is 0 V, active on rising edge
Terminal descriptions
xCLKI: Receives sampling clock from external source
xCLKO: Outputs the internal input scan or internal output scan clock, or thepulse generated from xCLKI when in external clock mode.
Input clock rate
USB-1808: 125 kHz
USB-1808X: 500 kHz
Clock pulse width
xCLKI: 400 ns min
xCLKO: 400 ns min
Input type : Schmitt trigger, 33 Ω series resistor, 47 kΩ pull-down to ground
Schmitt trigger hysteresis: 0.4 V to 1.2 V
Input high voltage: 2.2 V min, 5.5 V absolute max
Input low voltage: 1.5 V max, –0.5 V absolute min, 0 V recommended min
Output high voltage: 4.4 V min (IOH = –50 µA); 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

Data FIFO: 4 kS analog input/2 kS analog output
Non-volatile memory: 32 KB (28 KB firmware storage, 4 KB calibration/user data)

Power

Supply current (quiescent current): 305 mA
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.
+VO user output voltage range: 4.5 V min to 5.25 V max
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+VO user output current: 10 mA max

USB

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

Environmental

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

External Trigger

Trigger source: ITRIG for inputs, OTRIG for outputs
Trigger mode: Software programmable for edge or level sensitive, rising or fallingedge, high or low level. Power on default is edge sensitive, rising edge.
Trigger latency: 1 µs + 1 clock cycle max
Trigger pulse width: 100 ns min
Input type: Schmitt trigger, 33 Ω series resistor and 49.9 kΩ pull-down to ground
Schmitt trigger hysteresis: 0.4 V to 1.2 V
Input high voltage: 2.2 V min, 5.5 V absolute max
Input low voltage: 1.5 V max, –0.5 V absolute min, 0 V recommended min

MechanicalSignal I/O Connector
Standard: 2 banks of screw-terminals (wire gauge range 16 AWG to 30 AWG)
OEM: Two 1 × 28 pin 0.1 in. pitch headers
Dimensions (L × W × H)
Standard: 127 × 89.9 × 35.6 mm (5.00 × 3.53 × 1.40 in.)
OEM: 119.38 × 86.36 × 1.57 (4.7 × 3.4 × 0.062 in.)
User connection length: 3 m (9.84 ft) max

Pattern Trigger

Trigger source: DIO0 – DIO3
Trigger types: Above pattern, Below pattern, Equal pattern, or Not equal pattern
Trigger stability: Digital port must be stable for 50 ns to be recognized as a pattern
Trigger bit width: Up to 4, adjustable through bitmask
Trigger latency: Up to 1 scan period

Order Information

Software also Available from MCC

HardwareTracerDAQ Pro

Out-of-the-box virtual instrument suite with strip
chart, oscilloscope, function generator, and rate
generator – professional version

DASYLabIcon-based data acquisition, graphics, control, andanalysis software

Part No.

Description

USB-1808

18-bit, eight-channel, 50 kS/s per channel
simultaneous-sampling DAQ device with two
analog outputs, four digital I/O lines, two 32-bit
counter inputs, two quadrature encoder inputs,
and two timer outputs. Includes a USB cable.

USB-1808X

18-bit, eight-channel, 200 kS/s per channel
simultaneous-sampling DAQ device with two
analog outputs, four digital I/O lines, two 32-bit
counter inputs, two quadrature encoder inputs,
and two timer outputs. Includes a USB cable.

USB-1808-OEM

Board-only 18-bit, eight-channel, 50 kS/s perchannel simultaneous-sampling DAQ device with
two analog outputs, four digital I/O lines, two
32-bit counter inputs, two quadrature encoder
inputs, and two timer outputs.

USB-1808X-OEM

Board-only 18-bit, eight-channel, 200 kS/s perchannel simultaneous-sampling DAQ device with
two analog outputs, four digital I/O lines, two
32-bit counter inputs, two quadrature encoder
inputs, and two timer outputs.

Measurement Computing
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