The mioDAQ from NI has two 20-bit and two 16-bit flavors. Analog outputs come with two or four, with 16-bit DIO and counters.
USB data-acquisition (DAQ) devices have been on the market for many years and come in many varieties. What makes the mioDAQ series from NI different is its 20-bit vertical resolution on two models. If you don’t need 20 bits, you can opt for a 16-bit flavor. Let’s break down the mioDAQ USB-64xx series.
| Model | USB-6453 | USB-6451 | USB-6423 | USB-6421 |
| Resolution | 20 bit | 20 bit | 16 bit | 16 bit |
| Analog inputs | 32 SE/16 diff | 16 SE/8 diff | 32 SE/16 diff | 16 SE/8 diff |
| Sample rate | 1 MS/sec/ch (16 ch) | 1 MS/sec/ch (8 ch) | 250 kSa/sec muxed across all channels | 250 kSa/sec muxed across all channels |
| Analog outputs | 4 | 2 | 4 | 2 |
| Price | $3499 | $2499 | $1999 | $1099 |
All mioDAQ USB data-acquisition models include 16 digital I/O (DIO) channels and four counter/timer channels. Each of the 16 DIO channels can support switching frequencies up to 10 MHz and can be individually programmed as an input or output. The DIO channels support TTL levels (0-5 V). NI plans to add 1.8 V, 2.5 V, and 3.3 V. According to NI, the hardware for those additional voltages is already there but not currently enabled.
All models connect to a Windows PC through a USB-C port that also can transport all data, even when running 16 channels at 1 MSa/sec. The rear-panel USB port includes a receptable for a locking screw (cable included). According to NI, you can still power the mioDAQ from a USB-A port. The USB-6451 and USB-6453 models have 16 ADCs and need a USB3 port to power them. You will need a USB-C to USB-A cable or an adapter that can support USB3.
You can control the mioDAQ modules come with free software that you can download. If you’re writing your own application, you can download NI FlexLogger Lite software. It won’t work with DAQ Express so you’ll need to use Flexlogger Lite if you don’t want to write your own application. Of course, you can use LabVIEW and even LabWidows/CVI. You need to install NI DAQmx 24Q3.1 (24.6) driver to use mioDAQ. It also offers full support in the nidaqmx python library. You can also use the .NET Framework DAQmx assembly in .NET Core applications.
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