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Thomas Supplier


USB-AI16-16A &

16-Bit, 16-Channel,
USB Analog Input Modules

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US Prices
CDN Prices

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  • High-speed USB 2.0 device with up to 500kHz sampling rate
  • All functions fully software configurable
  • 16-bit with 16 single-ended or 8 differential inputs
  • Eight input ranges, unipolar or bipolar
  • Autocalibration and real-time hardware calibration and oversampling for accurate data
  • Unique channel-by-channel programmable gain
  • Data buffer for A/D
  • Synchronous, asynchronous, and timed trigger modes
  • 16 high-current digital I/O lines
  • 16-bit counter/timer for event counting or frequency generation
  • USB/104 form-factor for OEM embedded applications
  • Small, (4” x 4” x 1.25”) rugged industrial enclosure
  • OEM (board only) option features PC/104 module size and mounting compatibility
  • All required power drawn from USB port, no external power adapter required
  • Overvoltage protection
  • Alternate embedded USB connector


  • External power for high current capabilities
  • Extended temperature and DIN rail mounting provisions
  • OEM (board only) version with PC/104 mounting holes and PCB footprint for added flexibility in embedded applications
  • 4-20mA or 10-50mA inputs


The USB-AI16-16A and USB-AI16-16E offer an ideal solution for adding portable, easy-to-install high-speed analog and digital I/O capabilities to any computer with a USB port. These units are USB 2.0 high-speed devices, offering the highest speed available with the USB bus. The USB-AI16-16A is a 16-bit resolution A/D board capable of speeds up to 500kHz for its 16 single-ended or 8 differential analog input channels. USB-AI16-16E reaches speeds of 250kHz. Standard features also include 16 digital I/O lines and a 16-bit counter/timer—all packaged in a small, rugged, industrial enclosure.

These small, compact, multifunction I/O boards provide the user with everything needed to start acquiring, measuring, analyzing, and monitoring a variety of applications. These data acquisition boards can be used in many current real-world applications such as precision measurement, analysis, monitoring, and control in countless embedded applications.

These units are designed to be used in rugged industrial environments but are small enough to fit nicely onto any desk or testing station. The board itself is PC/104 sized (3.550 by 3.775 inches) and ships inside a steel powder-coated enclosure with an anti-skid bottom and a DIN-rail mounting capability.

The units feature eight standard analog voltage input ranges (independently configured), two factory current input ranges (4-20mA or 10-50mA) and include a data sample buffer. Model USB-AI16-16A features hardware real-time calibration capability which allows the card to continually compensate for offset/gain errors, giving a more accurate reading. To minimize noise, the board implements a technique called oversampling. Additionally, each channel contains its own analog ground pin which is helpful in reducing noise from external signal sources. A unique channel-by-channel programmable gain feature enables measurement of an assortment of large and small signals in one scan—all under software control at up to 500kHz. The boards data buffer and ability to trigger the A/D in real time assures synchronized sampling that is unaffected by other computer operations—an essential requirement for signal, vibration and transient analysis where high data rates must be sustained for short periods of time.

Analog to digital conversion starts or “A/D starts” are issued one of three ways: Software Start, Timer Start, or External Trigger Start. A/D starts are software configured to be either rising or falling edge. Additionally, A/D starts are software configured to be Single Channel or Scan. Single Channel samples data once from the next consecutive channel within the enabled set. A Scan samples data from all channels within the set at the fastest possible rate.

A fully programmable 8254 16-bit counter is provided with a maximum input frequency of 10MHz. The clock, gate (inputs) and output can be accessed externally for extended functionality. The counter can be configured in a variety of modes and has the ability to use external signals for its inputs.


The OEM (board only) version is perfect for a variety of embedded applications. What makes the OEM option unique is that its PCB size and pre-drilled mounting holes match the PC/104 form factor (without the bus connections). This ensures easy installation using standard standoffs inside most enclosures or systems. The board can be added to any PCI-104 or PC/104 stack by connecting it to a USB 2.0 port usually included on-board with embedded CPU form factors such as EBX, EPIC, and PC/104. This is especially important since many newer CPU chipsets do not support ISA and have plenty of USB ports. The USB-AI16-16 OEM board can also be installed using standoffs inside other enclosures or systems. For embedded OEM type applications, an additional miniature USB input header is provided in parallel with the type B connector.


  • Equipment monitoring
  • Environmental measurements
  • Embedded OEM
  • Education/Laboratory
  • Portable
  • Industrial Automation
  • Precision Measurement
  • Analysis, Monitoring, and Control



Available accessories include a wide variety of cables and screw terminal boards for quick and easy connectivity.


The USB-AI16-16A and USB-AI16-16E feature hotplug functionality allowing for quick connect/disconnect whenever you need additional I/O on your USB port. The module utilizes a high-speed custom function driver optimized for a maximum data throughput of 1MBps that is 50-100 times faster than the USB human interface device (HID) driver used by many competing products. This approach maximizes the full functionality of the hardware along with capitalizing the advantage of high-speed USB 2.0. These boards are supported for use in most operating systems and include a free Windows 98se/Me/2000/XP/2003 compatible software package. This package contains sample programs and source code in Visual Basic, Delphi, C Builder, and Visual C for Windows. Also incorporated is a graphical setup program in Windows. Third party support includes a Windows standard DLL interface usable from the most popular application programs. Embedded OS support include Windows XPe.

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Analog Inputs

ADC Type		Successive approximation
Sampling rate		
  USB-AI16-16A		500Ksamples/sec (maximum aggregate)
  USB-AI16-16E		250Ksamples/sec (maximum aggregate)
Resolution		16-bit
Number of channels	16 single-ended or 8 differential (software selectable)
Bipolar ranges		±1V, ±2V, ±5V, ±10V (software selectable)
Unipolar ranges		0-1V, 0-2V, 0-5V, 0-10V (software selectable)
4-20mA			Factory installed (optional)
10-50mA			Factory installed (optional)
Board Calibration	VREF LOW:  AGND	
			VREF HIGH:  9.90V ± 0.0299V				
System Calibration	Program provided to calibrate entire system
Calibration Hardware	
  USB-AI16-16A		Calibrated real-time output for offset/gain errors
  USB-AI16-16E		NONE
Input impedance		1M
A/D Start Sources  	Software Start, Timer Start, and External Start Trigger 
			(rising or falling edge; software selectable)
A/D Start Enable	Externally supplied (pulled-up; active-high )
A/D Start Types  	Single Channel or Scan (software selectable)
Channel Oversampling	0-255 consecutive samples/channel (software selectable)
Overvoltage protection	-40 to  55V
Crosstalk		No crosstalk present below 400KHz
			-60dB @ 500KHz

Digital I/O

Lines			16, programmable as inputs or outputs in groups of 8 (pulled-up)
Input voltage		Logic low:	0V(min) to 0.8V(max)
			Logic high	2V(min) to 5V(max)
Input current		±20µA (max)
Output voltage		Logic low:	0V(min) to 0.55V(max)
			Logic high:	2V(min) to 5V(max)
Output current		Logic low	64mA(max) sink
			Logic high	32mA(max) source	


Type			82C54 programmable interval counter
Available Counters	Counter 0
Input Frequency 	10MHz (max)
Counter size		16-bit  
Clock 			Internal 10MHz or Externally supplied 
			(software selectable; pulled-up)
Clock Period		100ns (min)
Clock Pulse Width High	30ns (min)
Clock Pulse Width Low	40ns (min)
Gate			Externally supplied (pulled-up; active-high)
Output			External (pulled-up)

Voltage/Current		Same as Digital I/O


Operating Temperature	0° to  70°C, optional -40° to  85°C
Storage Temperature	-40° to  105°C
Humidity		5% to 90% RH, without condensation
Board Dimensions	PC/104 format, 3.550” by 3.775” and mounting holes 

Power required		 5V at 330mA typ*

*USB 2.0 spec defines a device in terms of a unit load. A unit load is defined to be 100mA. Devices drawing an absolute maximum of one unit load is considered to be low-powered and devices drawing an absolute maximum of five unit loads is considered to be high-powered. Because this spec is not strictly adhered to, it is best to verify the USB port's power capabilities before operation. This card, according to the USB 2.0 spec, is a high powered device. An optional external power supply can be ordered if the USB port cannot support high powered devices.

If using more than a total of 500mA, use optional 9 VDC (on board voltage regulator outputs 5 VDC to card) external power supply and remove VUSB jumper and place jumper on VEXT. Then plug in external power before plugging into USB port . This option will give you a total of 1000mA available.

Included with your board

The following components are included with your shipment:
  • Board installed in labeled enclosure
  • 6’ USB cable
  • Software Master CD (PDF user manual installed with product package)
  • Printed USB I/O Quick-Start Guide

Part Number Price(USD)
USB-AI16-16A Advanced version, 16-Bit, 500kHz, with autocalibration
USB-AI16-16E Economy version. 16-Bit. 250kHz, with software calibration
STB-68 Screw Terminal Board
C68PS18L 68-Pin SCSI 18" shielded cable
MP104-DIN DIN rail mounting provision
STB-68 Kit Used for mounting the STB-68 to the enclosure of both the USB-AI and Fast USB-DIO Series of USB products. Includes STB-68, cable and specialized mounting hardware. $89.00
-OEM Board only version (no enclosure)
-P External power and AC/DC adapter
-T Extended Operating Temperature (-40°C to 85°C)
Call 4-20mA or 10-50mA inputs
Call 16 current inputs when factory configured as single-ended
Call 8 current inputs when factory configured as differential
Call DIO lines can be configured with pull down resistors
View / Download Manual (in .pdf format)
Acquisition Control Communications Engineering / Systems
View / Download Data Sheet (in .pdf format)
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