USB-1608G Series
16-Bit High-Speed Multifunction DAQ Devices
Features• 16-bit high-speed USB devices• Acquisition rates up to 500 kS/s
• 8 differential (DIFF) or 16 singleended (SE) analog inputs• Up to 2 analog outputs• 8 digital I/O• Two 32-bit counter inputs
USB-1608G Series provides eight differential or 16 single-ended analog inputs,
two analog outputs (USB-1608GX-2AO), 8 digital I/O, and one counter input.

Overview

Vista®XP 32/64-bit• Linux®

The USB‑1608GX-2AO standard and OEM version offers two, 16-bit analog output
channels with DAC rates up to 500 kS/s.

• Android™

Retrigger Mode

USB-1608G Series devices provide 16-bit
analog inputs that are software-selectableas eight DIFF or 16 SE inputs. These devices
also support input ranges of ±10 V, ±5 V,±2 V, and ±1 V that are software-selectable
per channel.

Users can set up repetitive analog input
trigger events. The trigger is automatically re-armed after it is activated. TheA/D trigger count (the number of samples
you want per trigger) is configurable withsoftware.

Analog Output(USB-1608GX-2AO only)

Digital I/O

The USB-1608GX-2AO standard/OEM
board has two 16-bit analog outputs thatcan be updated at a rate of 250 kS/s perchannel; one output can be updated ata rate of 500 kS/s. The output range isfixed at ±10 V.

Eight bidirectional digital I/O lines areindividually configurable for input oroutput. The DIO terminals can detect thestate of any TTL-level input. Users canconfigure for pull-up (+5 V) or pull-down(0 V) with an onboard jumper.

Measurement Computing

Counter Input
Two 32-bit event counters are providedto count TTL pulses. The counters accept
inputs of up to 20 MHz.

Timer Output
The PWM timer output generates a pulse
output with a programmable frequency
in the range of 0.0149 Hz to 32 MHz. Thetimer output parameters are softwareselectable.

USB-1608G Series Selection Chart
Model

AnalogInputsSampleRate (max)AnalogOutputs

SignalI/O

USB Cable
and SW CD

USB-1608G

16 SE/8 DIFF

250 kS/s0

Screw
Terminal✔

USB-1608GX

16 SE/8 DIFF

500 kS/s

0Screw
Terminal✔

USB-1608GX-2AO

16 SE/8 DIFF

500 kS/s2Screw
Terminal✔

USB-1608G-OEM

16 SE/8 DIFF

250 kS/s

0Header–USB-1608GX-OEM

16 SE/8 DIFF

500 kS/s

0Header–USB-1608GX-2AO-OEM

16 SE/8 DIFF

500 kS/s

2Header–Trigger Input
USB-1608G Series devices have an external digital trigger input. The trigger
mode is software-selectable for edge- orlevel-sensitive mode. You can configureedge-sensitive mode for either rising orfalling edge. In level-sensitive mode, you
can configure for either high or low level.
The default setting at power up is edgesensitive, rising edge.

• OEM version availableSupported Operating Systems• Windows® 11/10/8/7/

USB-1608G Series devices are low-cost, high-speed, analog and digital I/O USB
devices. All of these devices offer up to eight DIFF or 16 SE analog inputs, eight
digital I/O channels, two counter inputs, and one timer output.

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USB-1608G Series
Overview
USB-1608G Series Block Diagram
Calibration
Voltage
Sources

PGA

Mux

A/D88Signal I/O Connector

Amp

D/ARegisters

Amp

D/ARegisters

DIO
Protection

SPIFPGASPITrigger
A/D Clock In
A/D Clock Out
Counter In 0
Counter In 1Timer Out

BitwiseProgrammable
DIO

VBUS
(5 V)
PowerSupplies

USB

D+/D–

FIFO Data
ClockBus Bus

Signal I/O Connector

USB-1608GX-2AO standard/OEM only

8+16.5 V- 16.5 V
1.2 V
3.3 V
5V

AI

SPIAI

D/A Clock In
D/A Clock Out
USB-1608GX-2AO
standard/OEM
only

Microcontroller with
High-Speed
USB 2.0
Compliant Interface

3.3 V
Always On
ENABLEs

EEPROM

CrystalOscillator

Clock Output

USB-1608G Series OEM Versions

The AI clock pin outputs the signal from the internal clock.

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.

Calibration
The USB-1608G Series is factory-calibrated using a NIST-traceablecalibration process. Specifications are guaranteed for one year.
The USB-1608G Series also supports field calibration for users
to calibrate the device locally with the InstaCal utility.

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.

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USB-1608G Series
Software
Software Support
USB-1608G Series devices are supported by the software in the table below.
Ready-to-Run Applications

DAQami™

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 is included with the free MCC DAQ Software bundle.

InstaCal™

TracerDAQ™ andTracerDAQ Pro

An interactive installation, configuration, and test utility for MCC hardware. Windows OS
InstaCal is included with the free MCC DAQ Software bundle.
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.

UL for Android™

Library of Java classes for programmers who develop apps for Android-based mobile devices.
UL for Android communicates with select MCC DAQ devices. Supports Android project development on Windows, Linux, Mac OS X.
UL for Android is included with the free MCC DAQ Software bundle.

Application-Specific Programming Support
ULx forNI LabVIEW™

DASYLab®

MATLAB driver®

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.
High-level language and interactive environment for numerical computation,visualization, and programming. The Mathworks Data Acquisition Toolbox™ allows users toacquire data from most MCC PCI and USB devices.
Visit www.MathWorks.com for more information about the Data Acquisition Toolbox.

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USB-1608G SeriesSpecifications
Specifications

Common mode rejection ratio
fIN = 60 Hz, all input ranges: 86 dB
Crosstalk
Adjacent differential mode channels, DC to 100 kHz: –75 dB
Input coupling: DC
Sampling rate (software-selectable)
USB-1608G: 0.0149 Hz to 250 kHz
USB-1608GX/1608GX-2AO: 0.0149 Hz to 500 kHz
Trigger source: TRIG (refer to “External Trigger” on page 5)
Sample clock source: Internal A/D clock or external A/D clock (AICKI terminal)
Burst mode: Software-selectable using the internal A/D clock; always enabled
when using the external clock (AICKI terminal)
USB-1608G: 4 µs
USB-1608GX/1608GX-2AO: 2 µsThroughput
Software paced: 33 to 4000 S/s typ, system dependent
Hardware paced
USB-1608G: 250 kS/s max		USB-1608GX/1608GX-2AO: 500 kS/s max
Channel gain queue: Up to 16 elements; software-selectable range for each channel
Warm-up time:15 minutes min

These specifications apply to both standard and OEM versions unless noted.

Analog Input

A/D converter type: Successive approximation
ADC resolution: 16 bits
Number of channels: 8 DIFF, 16 SE; software-selectable
Input voltage range: ±10 V, ±5 V, ±2 V, ±1 V; software-selectable per channel
Absolute maximum input voltage
CHx relative to AGND: ±25 V max (power on); ±15 V max (power off)
Input Impedance: 1 GΩ (power on); 820 Ω (power off)
Input bias current: ±10 nA
Input bandwidth, all input ranges, small signal (–3 dB)		USB-1608G: 750 kHz		USB-1608GX/1608GX-2AO: 870 kHz
Input capacitance: 60 pf
Maximum working voltage (signal + common mode)±10 V range: ±10.2 V max relative to AGND
±5 V range: ±10.2 V max relative to AGND
±2 V range: ±9.5 V max relative to AGND
±1 V range: ±9.0 V max relative to AGND

Analog Input DC Voltage Measurement
All Values are (±)

Range

Gain Error(% of Reading)

Offset Error(µV)

INL Error(% of Range)

Absolute Accuracy
at Full Scale(µV)

Gain Temperature
Coefficient(% reading/°C)

Offset Temperature
Coefficient(µV/°C)±10 V0.024

9150.0076

40750.0014

47±5 V0.024

6860.0076

22660.0014

24±2 V

0.024

336

0.00769680.0014

10±1 V

0.024

2450.0076

5610.0014

5** Settling time is defined as the expected accuracy after one conversion whenswitching from a channel with a DC input at one extreme of full scale to anotherchannel with a DC input at the other extreme of full scale. Both input channels
are configured for the same input range.

Noise Performance*Range
±10 V
±5 V
±2 V
±1 V

Counts
6679LSBrms
0.91
0.91
1.06
1.36

Analog Output (USB-1608GX-2AO only)

Number of channels: 2 (leave unused AOUTx output channels disconnected)
Resolution: 16 bits
Output range: ±10 V (calibrated)
Output transient
Host computer is reset, powered on, suspended, or a reset command isissued to the device		Duration: 500 µs		Amplitude: 2 V pk-pk
Powered off		Duration: 10 ms		Amplitude: 7 V peak
Differential non-linearity: ±0.25 LSB typ; ±1 LSB max
Output current
AOUTx: ±3.5 mA max
Output short-circuit protection
AOUTx connected to AGND: Unlimited duration
Output coupling: DCPower on and reset stateDACs cleared to zero-scale: 0 V, ±50 mV (AOUTx defaults to 0 V when the hostis reset, powered on, suspended, or a reset command is issued to the device)
Output noise: 30 µVrms
Trigger source: TRIG (refer to “External Trigger” on page 5)
Sample clock source: Internal D/A clock or external D/A clock (AOCKI terminal)
Output update rate: 500 kHz/number of channels in the scan
Settling TimeTo rated accuracy, 10 V step: 40 µs
Slew rate: 9 V/µs
Throughput
Software paced: 33 S/s to 4000 S/s typ, system-dependentHardware paced: 500 kS/s max, system-dependent* 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.

Settling Time**
USB-1608G
Range

±10 V
±5 V
±2 V
±1 VRange

±10 V
±5 V
±2 V
±1 V

4 µS settling
accuracy(% FSR)

6 µS settling
accuracy(% FSR)

10 µS settling accuracy(% FSR)
0.00150.00150.00150.00150.00610.00310.00610.00310.00610.0031
0.00610.0031
USB-1608GX/1608GX-2AO
2 µS settling
accuracy(% FSR)
0.1251
0.06870.06870.0687

Measurement Computing

4 µS settling
accuracy(% FSR)
0.00310.00310.00310.00319 µS settling
accuracy(% FSR)
0.00150.00150.00150.0015(508) 946-5100

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USB-1608G SeriesSpecifications
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

Calibrated Absolute Accuracy
Range: ±10 V
Absolute accuracy ( ± LSB): 16.0

Calibrated Absolute Accuracy Components
Range: ±10 V% of reading: ±0.0183
Offset (±mV): 1.831
Offset Tempco (µV/°C): 12.7
Gain Tempco (ppm of range/°C): 13

Counter Input

Terminal names: CTR0, CTR1
Number of channels: 2 channels
Resolution: 32-bit
Counter type: Event counter
Input type: Schmitt trigger, 33 Ω series resistor, 47 kΩ pull-down to ground
Input source:
CTR0 (terminal 52)
CTR1 (terminal 51)
Counter read/Writes rates (Software-paced) : 33 to 8000 reads/writes per second
typ, system dependent
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: 20 MHz, max
High pulse width: 25 ns, min
Low pulse width: 25 ns, min

Analog Output Relative Accuracy
Range: ±10 V
Relative accuracy (INL): 4.0 typAnalog Input/Output Calibration

Recommended Warm-up Time: 15 minutes min
Calibration method: Self-calibration (firmware)
Calibration interval: 1 year (factory calibration)
AI calibration reference+5 V, ±2.5 mV max (actual measured values stored in EEPROM)
Tempco: 5 ppm/°C max
Long term stability: 15 ppm/1000 hours
AOUTx calibration procedure (USB-1608GX-2AO only)
The AOUTx terminals are internally routed to the AI circuit. For best results,disconnect AOUTx connections at the terminal block before calibrating.

Timer Output

Digital I/OTimer terminal name: TMR
Timer type: PWM output with count, period, delay, and pulse width registers
Output value: Idle low with pulses high, software-selectable output invert
Internal clock frequency: 64 MHz
Register widths: 32-bit
High pulse width: 15.625 ns min
Low pulse width: 15.625 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

Digital type: CMOS
Number of I/O: 8Configuration: Bit-configurable as input (power on default) or output
Pull-up configuration: 47 kΩ resistors configurable as pull-up/down (default)
via internal jumper (W1).
Digital I/O transfer rate (system-paced): 33 to 8000 port reads/writes or single
bit reads/writes per second typ, system dependent.
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

MemoryData FIFO:
USB-1608G/1608GX: 4 kS analog input
USB-1608GX-2AO: 4 kS analog input, 2 kS analog output
Non-volatile memory: 32 KB (28 KB firmware storage, 4 KB calibration/user data)

External Trigger

Trigger source: TRIG input
Trigger mode: Software configurable 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

PowerSupply current
The total quiescent current requirement includes up to 10 mA for the Status LED; this does not include any potential loading of the digital I/O bits,+5 V terminal, or the AOUTx outputs (USB-1608GX-2AO only).
Quiescent Current		USB-1608G/1608GX: 230 mA		USB-1608GX-2AO: 260 mA+5 V user output voltage range (available at Terminal 43): 4.5 V min to 5.25 V max+5 V user output current (available at terminal 43): 10 mA max

External Clock I/O

Terminal names
AICKI, AICKO
USB-1608GX-2AO: AICKI, AICKO AOCKI, AOCKO
Terminal types
AxCKI: Input, active on rising edge
AxCKO: Output, power on default is 0 V, active on rising edge
Terminal descriptions
AxCKI: Receives sampling clock from external source
AxCKO: Outputs the internal sampling clock (D/A or A/D clock) or the pulse
generated from AxCKI when in external clock mode.
Input clock rate
USB-1608G: 250 kHz max
USB-1608GX/1608GX-2AO: 500 kHz max
Clock pulse width
AxCKI: 400 ns min
AxCKO: 400 ns min

Measurement Computing(508) 946-5100

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

MechanicalSignal I/O connector-OEM models: Two 28-pin, 0.1 in. pitch headers
All other devices: 2 banks of screw-terminal blocks (wire gauge range
16 AWG to 30 AWG)
Dimensions (L × W × H):
Standard version: 127 × 89.9 × 35.6 mm (5.00 × 3.53 × 1.40 in.)OEM version: 121.92 × 86.36 × 15.24 (4.80 × 3.40 × 0.60 in.)5info@mccdaq.com

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USB-1608G Series
Ordering
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,
and analysis software

Part No.

Description

USB-1608G

16-channel, 250 kS/s sampling DAQ device withtwo 32-bit counter inputs, one timer output, andeight digital I/O lines. Includes a USB cable andMCC DAQ software.

USB-1608GX

16-channel, 500 kS/s sampling DAQ device withtwo 32-bit counter inputs, one timer output, andeight digital I/O lines. Includes a USB cable andMCC DAQ software.

USB-1608GX-2AO

16-channel, 500 kS/s sampling DAQ device with
two analog outputs, two 32-bit counter inputs,
one timer output, and eight digital I/O lines.
Includes a USB cable and MCC DAQ software.

USB-1608G-OEM

Board-only DAQ device with 16-channels,
250 kS/s sampling, two 32-bit counter inputs,
one timer output, and eight digital I/O lines.

USB-1608GX-OEM

Board-only DAQ device with 16-channels,
500 kS/s sampling, two 32-bit counter inputs,
one timer output, and eight digital I/O lines.

USB-1608GX-2AO-OEM

Board-only DAQ device with 16-channels,
500 kS/s sampling, two analog outputs, two
32-bit counter inputs, one timer output, andeight digital I/O lines.

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