The U3-HV is a USB Multifunction Data Acquisition device with 4 dedicated high-voltage analog inputs, 12 flexible I/O, and 4 dedicated digital I/O channels.
The flexible I/O can be configured as either digital or analog, thus providing up to 16 analog inputs, or up to 16 digital I/O. It also has two 10-bit analog outputs, up to 2 counters, and up to 2 timers.
The first 4 I/O lines are dedicated high-voltage analog inputs. The remaining 12 I/O lines (FIO and EIO ports) can be individually configured as digital input, digital output, or analog input. In addition, up to 2 of these lines can be configured as timers, and up to 2 of these lines can be configured as counters.
The first 8 I/O lines (FIO0-FIO7) appear on built-in screw terminals. The other 8 flexible I/O lines (EIO0-EIO7) are available on the DB15 connector.
The LabJack U3 has up to 16 analog inputs available on the flexible I/O lines. Single-ended measurements can be taken of any line compared to ground, or differential measurements can be taken of any line to any other line.
Analog input resolution is 12-bits. On the U3-HV, the input range of the 4 dedicated high-voltage analog input channels is ±10 volts or -10/+20 volts. The range of the remaining 12 flexible I/O inputs is typically 0-2.4 volts or 0-3.6 volts, and the range of differential analog inputs is typically ±2.4 volts (pseudobipolar only). For valid measurements, the voltage on every analog input pin, with respect to ground, must be within -0.3 to +3.6 volts.
Command/response (software timed) analog input reads typically take 0.6-4.0 ms depending on the number of channels and communication configuration. Hardware timed input streaming has a maximum rate that varies with resolution from 2.5 ksamples/s at 12-bits to 50 ksamples/s at about 10-bits.
The LabJack U3 has 2 analog outputs (DAC0 and DAC1) that are available on the screw terminals. Each analog output can be set to a voltage between 0 and 5 volts with 10-bits of resolution.
The analog outputs are updated in command/response mode, with a typical update time of 0.6-4.0 ms depending on communication configuration. The analog outputs have filters with a 3 dB cutoff around 16 Hz, limiting the frequency of output waveforms to less than that.
The LabJack U3 has up to 20 digital I/O channels. 16 are available from the flexible I/O lines, and 4 dedicated digital I/O (CIO0-CIO3) are available on the DB15 connector. Each digital line can be individually configured as input, output-high, or output-low. The digital I/O use 3.3 volt logic and are 5 volt tolerant.
Command/response (software timed) reads/writes typically take 0.6-4.0 ms depending on communication configuration. The first 16 digital inputs can also be read in a hardware timed input stream where all 16 inputs count as a single stream channel.
Up to 2 flexible I/O lines can be configured as timers. The timers are veryvflexible, providing options such as PWM output, pulse/period timing, pulse counting, and quadrature input.
Up to 2 flexible I/O lines can be configured as 32-bit counters.
All I/O lines on the U3 are protected against minor overvoltages. The FIO lines can withstand continuous voltages of up to ±10 volts, while the EIO/CIO lines withstand continuous voltages of up to ±6 volts.
High Channel Count Applications:
By using USB hubs, many LabJacks can be interfaced to a single PC, providing an inexpensive solution for high channel count applications.
LabJack U3s and U12s are the only USB analog to digital converters recognised by Radio-Sky Pipe II, the strip chart recorder and data logging software published by Jim Sky, which is widely used by amateur radio astronomers.
A typical setup is shown below where the LabJack U3 converts the analog voltage output from a UKRAA VLF Receiver to a digital signal which can be displayed on a Radio-Sky Pipe strip chart.
As the professional version of Radio-Sky Pipe can log up to 8 channels of data, a variety of instruments can be fed though a single LabJack U3 and logged in Radio-Sky Pipe.
Please click here for the LabJack Datasheet and application notes.