Measurement Computing USB-1608FS-Plus-OEM User manual

USB-1608FS-Plus-OEM
Analog and Digital I/O
Document Revision 2A
December 2014
©Copyright 2014
User's Guide

HM USB-1608FS-Plus-OEM
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Other product and company namesmentioned herein are trademarks or trade names of their respective
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reproduced, stored in a retrieval system, or transmitted, in any form by any means, electronic,mechanical, by
photocopying, recording, or otherwise without the prior written permission of Measurement Computing
Corporation.
Notice
Measurement Computing Corporation does not authorize any Measurement Computing Corporation product for
use in life support systems and/or devices without prior written consent from Measurement Computing
Corporation. Life support devices/systems are devices or systems that, a) are intended for surgical implantation
into the body, or b) support or sustain life and whose failure to perform can be reasonably expected to result in
injury. Measurement Computing Corporation products are not designed with the components required, and are
not subject to the testing required to ensure a level of reliability suitable for the treatment and diagnosis of
people.

3
Table of Contents
Preface
About this User's Guide .......................................................................................................................5
What you will learn from this user's guide .........................................................................................................5
Conventions in this user's guide .........................................................................................................................5
Where to find more information.........................................................................................................................5
Chapter 1
Introducing the USB-1608FS-Plus-OEM .............................................................................................6
Functional block diagram...................................................................................................................................7
Chapter 2
Installing a USB-1608FS-Plus-OEM.....................................................................................................8
Unpacking...........................................................................................................................................................8
Downloading the software..................................................................................................................................8
Installing the hardware .......................................................................................................................................8
Installing on a Windows platform..................................................................................................................................... 8
Installing on an Android platform..................................................................................................................................... 8
Calibrating the hardware.....................................................................................................................................8
Chapter 3
Functional Details .................................................................................................................................9
Analog input modes............................................................................................................................................9
Software paced.................................................................................................................................................................. 9
Hardware paced ................................................................................................................................................................ 9
BURSTIO......................................................................................................................................................................... 9
Board components............................................................................................................................................10
USB connector.................................................................................................................................................................10
LED .................................................................................................................................................................................10
Header connectors............................................................................................................................................................11
Signal connections............................................................................................................................................11
Analog input....................................................................................................................................................................11
Channel-Gain queue ........................................................................................................................................................11
Digital I/O........................................................................................................................................................................12
Pull-up/down configuration .............................................................................................................................................12
Counter input...................................................................................................................................................................13
SYNC I/O ........................................................................................................................................................................13
Trigger input....................................................................................................................................................................13
Reserved ..........................................................................................................................................................................13
Ground.............................................................................................................................................................................13
Power output....................................................................................................................................................................13
Accuracy...........................................................................................................................................................14
Synchronized operations...................................................................................................................................16
Mechanical drawings........................................................................................................................................16
Chapter 4
Specifications......................................................................................................................................17
Analog input .....................................................................................................................................................17
Accuracy...........................................................................................................................................................17
Analog input DC voltage measurement accuracy............................................................................................................17
Noise performance...........................................................................................................................................................18
Digital input/output...........................................................................................................................................18
External trigger.................................................................................................................................................19
External clock input/output...............................................................................................................................19
Counter section.................................................................................................................................................20

USB-1608FS-Plus-OEM User's Guide
4
Memory ............................................................................................................................................................20
Microcontroller.................................................................................................................................................20
Power................................................................................................................................................................21
General .............................................................................................................................................................21
Environmental ..................................................................................................................................................21
Mechanical .......................................................................................................................................................21
Header connector and pinout............................................................................................................................21

5
Preface
About this User's Guide
What you will learn from this user's guide
This user's guide describes the Measurement Computing USB-1608FS-Plus-OEM data acquisition device and
lists device specifications.
Conventions in this user's guide
For more information
Text presented in a box signifies additional information and helpful hints related to the subject matter you are
reading.
Caution! Shaded caution statements present information to help you avoid injuring yourself and others,
damaging your hardware, or losing your data.
bold text Bold text is used for the names of objects on a screen, such as buttons, text boxes, and check boxes.
italic text Italic text is used for the names of manuals and help topic titles, and to emphasize a word or phrase.
Where to find more information
Additional information about the USB-1608FS-Plus-OEM is available on our website at www.mccdaq.com.
You can also contact Measurement Computing Corporation with specific questions.
Knowledgebase: kb.mccdaq.com
Tech support form: www.mccdaq.com/support/support_form.aspx
Email: [e-mail]
Phone: [phone] and follow
For international customers, contact your local distributor. Refer to the International Distributors section on our
website at
the instructions for reaching Tech Support
www.mccdaq.com/International.

6
Chapter 1
Introducing the USB-1608FS-Plus-OEM
The USB-1608FS-Plus-OEM is a USB 2.0 full-speed analog input and digital I/O data acquisition device
providing the following features:
Eight 16-bit single-ended (SE) analog input channels
Each input channel has a dedicated A/D converter for simultaneous sampling.
Software-selectable analog input ranges of ±10 V, ±5 V, ±2 V, and ±1 V
Eight individually configurable digital I/O channels
One 32-bit event counter
One external digital trigger input
Bidirectional external clock for synchronous operation with more than one device.
Two header connectors for field wiring connections
The USB-1608FS-Plus-OEM device is compatible with both USB 1.1 and USB 2.0 ports. The speed of the
device may be limited when using a USB 1.1 port due to the difference in transfer rates on the USB 1.1 versions
of the protocol (low-speed and full-speed).
The device is powered by the +5V USB supply from the computer, requiring no external power.
Caution! There are no product safety, electromagnetic compatibility (EMC), or CE marking compliance
claims made for the USB-1608FS-Plus-OEM. The USB-1608FS-Plus-OEM is intended for use as
a component of a larger system. MCC can help developers meet their compliance requirements.
The end product supplier, however, is responsible for conforming to any and all compliance
requirements.

USB-1608FS-Plus-OEM User's Guide Introducing the USB-1608FS-Plus-OEM
7
Functional block diagram
USB-1608FS-Plus-OEM functions are illustrated in the block diagram shown here.
Figure 1. Functional block diagram

8
Chapter 2
Installing a USB-1608FS-Plus-OEM
Unpacking
As with any electronic device, you should take care while handling to avoid damage from static
electricity. Before removing the board from its packaging, ground yourself using a wrist strap or by simply
touching the computer chassis or other grounded object to eliminate any stored static charge.
Downloading the software
Refer to the USB-1608FS-Plus-OEM product page on the Measurement Computing website for information
about the supported software you can download.
Install the software before you install the hardware
The driver needed to run the device is installed when you install the software. Therefore, you need to install the
software package you plan to use before you install the hardware.
Installing the hardware
Installing on a Windows platform
Connect the USB-1608FS-Plus-OEM to a to an available USB port on the computer running Windows, connect
the USB cable to an available USB port on the computer or to an external USB hub connected to the computer.
Connect the other end of the cable to the USB connector on the device. No external power is required.
When connected for the first time, a Found New Hardware dialog opens when the operating system detects the
device. When the dialog closes, the installation is complete. The device LED turns on after the device is
successfully installed.
If the LED turns off
If communication is lost between the device and the computer, the LED turns off. To restore communication,
disconnect the USB cable from the computer and then reconnect it. This should restore communication, and the
LED should turn on.
Installing on an Android platform
Many Android devices include a standard A-type USB port to connect to the USB-1608FS-Plus-OEM. If your
device does not have a USB port, you may need a USB OTG cable in order for your Android device to host a
USB device. Refer to your Android device documentation for more information.
Calibrating the hardware
The Measurement Computing Manufacturing Test department performs the initial factory calibration. Return
the device to Measurement Computing Corporation when calibration is required. The recommended calibration
interval is one year.
Field calibration is not supported.

9
Chapter 3
Functional Details
Analog input modes
The USB-1608FS-Plus-OEM can acquire analog input data in three modes – software paced, hardware paced,
and BURSTIO.
Software paced
You can acquire one analog sample at a time in software-paced mode. You initiate the A/D conversion by
calling a software command. The analog value is converted to digital data and returned to the computer. You
can repeat this procedure until you have the total number of samples that you want.
The USB-1608FS-Plus-OEM can attain throughput rates up to 500 S/s using a software loop. This rate is
system-dependent.
Hardware paced
The USB-1608FS-Plus-OEM can acquire data from up to eight channels simultaneously in hardware-paced
mode. The analog data is acquired, converted to digital values, and written to an onboard FIFO buffer on the
device until you stop the scan. Data is transferred in blocks from the device to the memory buffer on your
computer.
The A/D converter is paced by either an internal or external clock source.
The maximum sampling rate is an aggregate rate. The total sample rate using hardware-paced mode is 400 kS/s
divided by the number of channels, with a maximum rate of 100 kS/s for any channel. You can acquire data
from one to four channels at 100 kS/s each, six channels at 66.7 kS/s each, and so on, up to eight channels at
50 kS/s each. You can start a hardware-paced scan with a software command. Optionally, hardware-paced scans
can be delayed by an external hardware trigger event.
BURSTIO
When using BURSTIO, the USB-1608FS-Plus-OEM can acquire data at a higher rate using the full capacity of
the 32 kilosample FIFO. The acquired data is read from the FIFO and transferred to a user buffer in the
computer after the acquisition is complete. You can initiate a single acquisition sequence of one to eight
channels with a software command. Optionally, BURSTIO scans can be delayed by an external hardware
trigger event.
When BURSTIO is enabled, the number of samples acquired in a scan is limited to the depth of the onboard
memory. The maximum sample rate in BURSTIO mode is an aggregate rate of 800 kS/s. The maximum per
channel sample rate is 100 kS/s for any or all channels.

USB-1608FS-Plus-OEM User's Guide Functional Details
10
Board components
Board components are shown in Figure 2.
1 Header connectors 21 to 40 3 USB connector
2 LED 4 Header connectors 1 to 20
Figure 2. Board components
USB connector
Receives the supplied USB cable. When connected to a computer or USB hub, the cable provides +5 V power
and communication. No external power supply is required.
LED
The LED indicates the USB communication status; it cannot be disabled.
LED behavior
LED state Indication
On – steady green The device is connected to a computer or external USB hub.
Blinks once A USB command is received.
Blinks continuously An analog input scan is in progress.

USB-1608FS-Plus-OEM User's Guide Functional Details
11
Header connectors
The header connectors provide connections for the analog inputs, analog ground, DIO, clock I/O, trigger,
counter, power output, and digital ground reference.
Header connector pinout (refer to Figure 2 for pin numbering)
Pin Signal Description Signal Name Pin Signal Description Signal Name
40 Digital ground GND AGND Analog ground 20
39 Power output +VO AGND Analog ground 19
38 Counter input CTR AGND Analog ground 18
37 Trigger input TRIG_IN RSVD Reserved 17
36 Sync I/O SYNC AGND Analog ground 16
35 DIO channel 7 DIO7 CH7 IN AI channel 7 15
34 Digital ground GND AGND Analog ground 14
33 DIO channel 6 DIO6 CH6 IN AI channel 6 13
32 Digital ground GND AGND Analog ground 12
31 DIO channel 5 DIO5 CH5 IN AI channel 5 11
30 Digital ground GND AGND Analog ground 10
29 DIO channel 4 DIO4 CH4 IN AI channel 4 9
28 Digital ground GND AGND Analog ground 8
27 DIO channel 3 DIO3 CH3 IN AI channel 3 7
26 Digital ground GND AGND Analog ground 6
25 DIO channel 2 DIO2 CH2 IN AI channel 2 5
24 Digital ground GND AGND Analog ground 4
23 DIO channel 1 DIO1 CH1 IN AI channel 1 3
22 Digital ground GND AGND Analog ground 2
21 DIO channel 0 DIO0 CH0 IN AI channel 0 1
USB connector
Signal connections
Analog input
You can connect up to eight analog input connections to the header connector containing pins 1 to 20 (CH0 IN
through CH7 IN.) Connect unused analog inputs to ground connectors during operation. For example, if you are
not using CH7 IN, ground this connector to AGND.
All analog input channels are configured for single-ended input mode. All analog input signals are referenced to
ground (AGND):
Connect the wire carrying the signal to be measured to CH# IN.
Connect the second wire to AGND.
The input voltage ranges are ±10 V, ±5 V, ±2.0 V, ±1.0 V.
For more information on analog signal connections
For more information on single-ended inputs, refer to the Guide to Signal Connections (this document is
available on our web site at www.mccdaq.com/signals/signals.pdf).
Channel-Gain queue
The channel-gain queue feature allows you to configure a different gain setting for each channel. The gain
settings are stored in a channel-gain queue list that is written to local memory on the device.
The channel-gain queue list can contain up to eight unique elements. The channel list must be in increasing
order. An example of a five element list is shown in the table below.

USB-1608FS-Plus-OEM User's Guide Functional Details
12
Sample channel-gain queue list
Element Channel Range
0 CH0 BIP1V
1 CH2 BIP2V
2 CH4 BIP10V
3 CH6 BIP1V
4 CH7 BIP5V
Carefully match the gain to the expected voltage range on the associated channel or an over range condition
may occur. Although this condition does not damage the device, it does produce a useless full-scale reading,
and can introduce a long recovery time due to saturation of the input channel.
Digital I/O
You can connect up to eight digital I/O lines to DIO0 through DIO7. Each digital channel is individually
configurable for input or output. During initial power on or reset the digital pins are set for input.
The digital I/O terminals can detect the state of any TTL-level input. Refer to the schematic shown in Figure 3.
Figure 3. Schematic showing switch detection by digital channel DIO0
If you set the switch to the +5 V input, DIO0 reads TRUE (1). When set to GND, DIO0 reads FALSE (0).
Pull-up/down configuration
All digital I/O lines are pulled up to USB +5V (HI) with a 47 kΩ resistor (default). You can change the
pull-up/down configuration using the internal jumper labeled DIO. You must remove the device housing to
access the jumper on the circuit board.
To set the jumper for pull-up or pull-down, complete the following steps.
1. Unplug the device from the computer.
2. Turn the device over and rest the top of the housing on a flat, stable surface.
Caution! The discharge of static electricity can damage some electronic components. Before removing the
USB-1608FS-Plus-OEM from its housing, ground yourself using a wrist strap or touch the
computer chassis or other grounded object to eliminate any stored static charge.
3. Remove the three screws from the bottom of the device using a #1 Philips head screwdriver.
4. Hold both the top and bottom sections together, turn the device over and rest it on the surface, then
carefully remove the top section of the case to expose the circuit board.
Figure 4 shows the location of the DIO jumper on the circuit board.
Figure 4. Pull-up/down jumper location
5. Configure the jumper for pull-up or pull-down, as shown in Figure 5.

USB-1608FS-Plus-OEM User's Guide Functional Details
13
Figure 5. Pull-up/down jumper configuration
6. Replace the top section of the housing, and fasten it to the bottom section with the three screws.
For more information on digital signal connections
For general information regarding digital signal connections and digital I/O techniques, refer to the Guide to
Signal Connections (available on our web site at www.mccdaq.com/signals/signals.pdf).
Counter input
The CTR connector is a 32-bit event counter that can accept frequency inputs up to 1 MHz. The internal counter
increments when the TTL levels transition from low to high.
SYNC I/O
The SYNC connector is a bidirectional I/O signal that can be configured as an input (default) or an output.
Configure as an external clock input to pace the A/D conversions from an external source. The SYNC
connector supports TTL-level input signals of up to 100 kHz.
Configure as an output that may be used to pace conversions on a second device and acquire data from
16 channels. Refer to page 16 for more information about synchronized operations.
Trigger input
The TRIG_IN connector is an external digital trigger input. The trigger mode is software-selectable for edge or
level sensitive. Edge sensitive mode is selectable for rising or falling. Level sensitive mode is selectable for
high or low.
Reserved
The RSVD connector is reserved for future use.
Ground
The analog ground (AGND) connectors provide a common ground for all analog channels.
The digital ground (GND) connectors provide a common ground for the digital, trigger, counter, and sync
channels and the power connector.
Power output
The PC +5V output connector can output up to 200 mA maximum. You can use this connector to supply power
to external devices or circuitry.
Caution! The PC +5V connector is an output. Do not connect it to an external power supply or you may
damage the device and possibly the computer.
The maximum output current that can be drawn by the USB-1608FS-Plus-OEM is 500 mA. This maximum
applies to most personal computers and self-powered USB hubs. Bus-powered hubs and notebook computers
may limit the maximum available output current to 100 mA. If the current requirement of the device exceeds
the current available from the computer, connect to a self-powered hub or power the computer with an external
power adapter.
When running applications with the device, each DIO bit can source up to 24 mA. The total amount of current
that can be sourced from the PC +5V, SYNC, and digital outputs is 200 mA max.

USB-1608FS-Plus-OEM User's Guide Functional Details
14
Accuracy
The overall accuracy of any instrument is limited by the error components within the system. Resolution is
often used incorrectly to quantify the performance of a measurement product. While "16-bits" or "1 part in
65,536" does indicate what can be resolved, it provides little insight into the quality, or accuracy, of an absolute
measurement.
Accuracy specifications describe the actual measurement achievable with a USB-1608FS-Plus-OEM. Accuracy
specifications are listed on page 17.
There are three types of errors which affect the accuracy of a measurement system:
offset
gain
nonlinearity
The primary error sources in a USB-1608FS-Plus-OEM are offset and gain. Nonlinearity is small, and is not
significant as an error source with respect to offset and gain.
Figure 6 shows an ideal, error-free transfer function. The typical calibrated accuracy of a USB-1608FS-Plus-
OEM is range-dependent. We use a ±10 V range as an example of what you can expect when performing a
measurement in this range.
Figure 6. Ideal ADC transfer function
The offset error is measured at mid-scale. Ideally, a zero volt input should produce an output code of 32,768.
Any deviation from this is an offset error. Figure 7 shows the transfer function with an offset error. The typical
offset error specification for a USB-1608FS-Plus-OEM on the ±10 V range is ±1.66 mV. Offset error affects all
codes equally by shifting the entire transfer function up or down along the input voltage axis.
The accuracy plots in Figure 7 are drawn for clarity and are not drawn to scale.

USB-1608FS-Plus-OEM User's Guide Functional Details
15
Figure 7. ADC transfer function with offset error
Gain error is a change in the slope of the transfer function from the ideal, and is typically expressed as a
percentage of full-scale. Figure 8 shows the USB-1608FS-Plus-OEMtransfer function with gain error. Gain
error is easily converted to voltage by multiplying the full-scale input (±10 V) by the error.
The accuracy plots in Figure 8 are drawn for clarity and are not drawn to scale.
Figure 8. ADC Transfer function with gain error
For example, a USB-1608FS-Plus-OEM exhibits a typical calibrated gain error of ±0.04% on all ranges. For the
±10 V range, this would yield 10 V × ±0.0002 = ±4 mV. This means that at full scale, neglecting the effect of
offset for the moment, the measurement would be within 4 mV of the actual value. Note that gain error is
expressed as a ratio. Values near ±FS (±10 V) are more affected from an absolute voltage standpoint than are
values near mid-scale, which see little or no voltage error.
Combining these two error sources in Figure 9, we have a plot of the error band at ±full scale (±10 V). This plot
is a graphical version of the typical accuracy specification of the product.
The accuracy plots in Figure 9 are drawn for clarity and are not drawn to scale.

USB-1608FS-Plus-OEM User's Guide Functional Details
16
Figure 9. Error band plot
Synchronized operations
You can connect the SYNC pin of multiple devices together in a master/slave configuration and acquire data
from the analog inputs of all devices using one clock.
When the SYNC pin is configured as an output, the internal A/D pacer clock signal is sent to the header
connector. You can output the clock to the SYNC pin of another device that is configured for A/D pacer input.
Mechanical drawings
Figure 10. USB-1608FS-Plus-OEM circuit board dimensions

17
Chapter 4
Specifications
All specifications are subject to change without notice.
Typical for 25°C unless otherwise specified.
Specifications in italic text are guaranteed by design.
Analog input
Table 1. General analog input specifications
Parameter Condition Specification
A/D converter type 16-bit successive approximation type
Number of channels 8 single-ended
Input configuration Individual A/D per channel
Sampling method Simultaneous
Absolute maximum input voltage CHx IN relative to GND ±15 V max
Input impedance 100 MΩ min
Input ranges Software-selectable per channel ±10 V, ±5 V, ±2 V, ±1 V
Sampling rate Hardware paced 0.01 S/s to 100 kS/s, software-selectable
Throughput Software paced 500 S/s all channels
Hardware paced (Note 1) (400 kS/s) / (# of channels) max,
100 kS/s max for any channel
BURSTIO ≤ 32,768 total samples
(uses onboard FIFO) (800 kS/s) / (# of channels) max,
100 kS/s max for any channel
Gain queue Software configurable. Up to eight
elements – one gain element per unique,
ordered channel.
Resolution 16 bits
No missing codes 16 bits
Crosstalk Signal DC to 25 kHz –80 dB
Trigger source Software-selectable External digital: TRIG_IN
Note 1: Maximum throughput when scanning in hardware paced mode is machine dependent.
Accuracy
Analog input DC voltage measurement accuracy
Table 2. Calibrated absolute accuracy
Range Accuracy (mV)
±10 V 5.66
±5 V 2.98
±2 V 1.31
±1 V 0.68

USB-1608FS-Plus-OEM User's Guide Specifications
18
Table 3. Accuracy components - All values are (±)
Range Gain error
(% of Reading) Gain error at FS
(mV) Offset (mV)
±10 V 0.04 4.00 1.66
±5 V 0.04 2.00 0.98
±2 V 0.04 0.80 0.51
±1 V 0.04 0.40 0.28
Noise performance
Table 4. Noise performance
Range Typical counts LSBrms
±10 V 10 1.52
±5 V 10 1.52
±2 V 11 1.67
±1 V 14 2.12
Table 4 summarizes the noise performance for the USB-1608FS-Plus-OEM. Noise distribution is determined by
gathering 50 K samples with inputs tied to ground at the user connector. Samples are gathered at the maximum
specified sampling rate of 100 kS/s.
Digital input/output
Table 5. Digital I/O specifications
Parameter Specification
Digital type 5V TTL
Number of I/O 8 (DIO0 through DIO7)
Configuration Independently configured for input or output
Pull-up/pull-down
configuration All pins pulled up to 5V via 47 K resistors (default).
May be changed to pull-down using an internal jumper.
Input high voltage
threshold 2.0 V min
Input high voltage limit 5.5 V absolute max
Input low voltage
threshold 0.8 V max
Input low voltage limit –0.5 V absolute min
0 V recommended min
Output high voltage 4.4 V min (IOH = –50 µA)
3.76 V min (IOH = –24 mA)
Output low voltage 0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 24 mA)
Power on and reset state Input

USB-1608FS-Plus-OEM User's Guide Specifications
19
External trigger
Table 6. External trigger specifications
Parameter Condition Specification
Trigger source External digital TRIG_IN
Trigger mode Software-selectable Edge or level sensitive: user configurable for CMOS
compatible rising or falling edge, high or low level.
Trigger latency 2 µs + 1 pacer clock cycle max
Trigger pulse width 1µs min
Input type Schmitt trigger, 47 kΩ pull-down to ground
Schmitt trigger hysteresis 1.01 V typ
0.6 V min
1.5 V max
Input high voltage threshold 2.43 V typ
1.9 V min
3.1V max
Input high voltage limit 5.5 V absolute max
Input low voltage threshold 1.42 V typ
1.0 V min
2.0 V max
Input low voltage limit -0.5 V absolute min
0 V recommended min
External clock input/output
Table 7. External clock I/O specifications
Parameter Condition Specification
Pin name SYNC
Pin type Bidirectional
Direction, software-selectable Input Receives A/D pacer clock from external source
Output Outputs internal A/D pacer clock
Input clock rate 100 kHz, max
Clock pulse width Input 1 µs min
Output 4 µs min
Input clock mode Edge sensitive, rising
Input type Schmitt trigger, 47 kΩ pull-down to ground
Schmitt trigger hysteresis 1.01 V typ
0.6 V min
1.5 V max
Input high voltage threshold 2.43 V typ
1.9 V min
3.1V max
Input high voltage limit 5.5 V absolute max
Input low voltage threshold 1.42 V typ
1.0 V min
2.0 V max
Input low voltage limit -0.5 V absolute min
0 V recommended min
Output high voltage 4.4 V min (IOH = –50 µA)
3.80 V min (IOH = –8 mA)
Output low voltage 0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 8 mA)

USB-1608FS-Plus-OEM User's Guide Specifications
20
Counter section
Table 8. Counter specifications
Parameter Specification
Pin name CTR
Counter type Event counter
Number of channels 1
Input type Schmitt trigger, 47 kΩ pull-down to ground
Input source CTR header pin
Resolution 32 bits
Schmitt trigger hysteresis 1.01 V typ
0.6 V min
1.5 V max
Input high voltage threshold 2.43 V typ
1.9 V min
3.1V max
Input high voltage limit 5.5 V absolute max
Input low voltage threshold 1.42 V typ
1.0 V min
2.0 V max
Input low voltage limit -0.5 V absolute min
0 V recommended min
Input frequency 1 MHz max
High pulse width 500 ns min
Low pulse width 500 ns min
Memory
Table 9. Memory specifications
Parameter Specification
Data FIFO 32,768 samples, 65,536 bytes
EEPROM 2,048 bytes (768 bytes calibration, 256 bytes user, 1,024 bytes DAQFlex)
Microcontroller
Table 10. Microcontroller specifications
Parameter Specification
Type High performance 32-bit RISC microcontroller