Measurement USB-1408FS User Manual

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USB-1208FS-Plus

User's Guide

Analog and Digital I/O

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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-1208FS-Plus ....................................................................................................... 6

Functional block diagram ................................................................................................................................... 6

Chapter 2

Installing the USB-1208FS-Plus ........................................................................................................... 7

What comes with your shipment? ....................................................................................................................... 7

Hardware .......................................................................................................................................................................... 7

Software ............................................................................................................................................................................ 7

Documentation ................................ ................................................................ ................................................................ .. 7

Unpacking........................................................................................................................................................... 7

Installing the software ........................................................................................................................................ 7

Installing the hardware ....................................................................................................................................... 7

Calibrating the hardware..................................................................................................................................... 8

Chapter 3

Functional Details ................................................................................................................................. 9

Analog input acquisition modes ......................................................................................................................... 9

Software paced .................................................................................................................................................................. 9

Hardware paced ................................................................................................................................................................ 9

External components ........................................................................................................................................ 10

USB connector .................................................................................................................................................................10

LED .................................................................................................................................................................................10

Screw terminals................................................................................................................................................................10

Signal connections ............................................................................................................................................ 12

Analog input ....................................................................................................................................................................12

Analog output ..................................................................................................................................................................14

Digital I/O ........................................................................................................................................................................15

Counter input ...................................................................................................................................................................16

External trigger input .......................................................................................................................................................16

SYNC I/O ........................................................................................................................................................................16

Power output ....................................................................................................................................................................16

Ground ................................................................................................................................................................ .............16

Accuracy ........................................................................................................................................................... 16

Synchronized operations ................................................................................................................................ ... 19

Power ................................................................................................................................................................ 19

Mechanical drawings ................................................................................................................................ ........ 20

Chapter 4

Specifications ...................................................................................................................................... 21

Analog input ..................................................................................................................................................... 21

Accuracy ..........................................................................................................................................................................22

Noise performance ...........................................................................................................................................................22

Analog output ................................................................................................................................................... 23

Digital input/output........................................................................................................................................... 23

External trigger ................................................................................................................................ ................. 24

External clock input/output............................................................................................................................... 24

USB-1208FS-Plus User's Guide

Counter ............................................................................................................................................................. 25

Memory ............................................................................................................................................................ 25

Microcontroller ................................................................................................................................................. 25

Power ................................................................................................................................................................ 25

General ............................................................................................................................................................. 26

Environmental .................................................................................................................................................. 26

Mechanical ....................................................................................................................................................... 26

Signal connector ............................................................................................................................................... 26

Differential mode pinout ..................................................................................................................................................27

Single-ended mode pinout ...............................................................................................................................................27

Declaration of Conformity .................................................................................................................. 28

About this User's Guide

What you will learn from this user's guide

This user's guide describes the Measurement Computing USB-1208FS-Plus 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. 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.

Preface

Where to find more information

Additional information about USB-1208FS-Plus hardware 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: techsupport@mccdaq.com  Phone: 508-946-5100 and follow the instructions for reaching Tech Support

For international customers, contact your local distributor. Refer to the International Distributors section on our website at www.mccdaq.com/International.

Chapter 1

Introducing the USB-1208FS-Plus

The USB-1208FS-Plus is an analog input and digital I/O data acquisition device that provides the following features:

 Eight analog input channels that are software configurable for either eight 11-bit single-ended inputs or

four 12-bit differential inputs

 Two 12-bit analog output channels  16 digital I/O channels that are independently-selectable as input or output in two 8-bit ports  32-bit event counter input for counting TTL pulses  External digital trigger input  Bidirectional terminal for external clocking or multi-unit synchronization  Screw terminals for field wiring connections

The device is powered by the +5 V USB supply from the computer. No external power is required.

Functional block diagram

Device functions are illustrated in the block diagram shown here.

Figure 1. USB-1208FS-Plus functional block diagram

Installing the USB-1208FS-Plus

What comes with your shipment?

Verify that the following hardware components are included in the shipment.

Hardware

 USB-1208FS-Plus  USB cable

Software

MCC DAQ CD

Documentation

 MCC DAQ Quick Start

The MCC DAQ Quick Start booklet provides an overview of the MCC DAQ software you received with the device, and includes information about installing the software. Please read this booklet completely before installing any software or hardware.

 DAQami Quick Start

The DAQami Quick Start insert provides information about the DAQami advanced data logging application, including a quick start procedure and quick reference guide.

Chapter 2

Unpacking

As with any electronic device, you should take care while handling to avoid damage from static electricity. Before removing the device 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.

Installing the software

Refer to the MCC DAQ Quick Start for instructions on installing the software on the MCC DAQ CD. Refer to the device product page on the Measurement Computing website for information about the included and optional software supported by the USB-1208FS-Plus.

Install the software before you install your device

The driver needed to run the USB-1208FS-Plus is installed with the software. Therefore, you need to install the software package you plan to use before you install the hardware.

For operation on a Windows operating system, we recommend that you run Windows Update to update your operating system with the latest USB drivers.

Installing the hardware

To connect the device to your system, turn on your computer and connect the USB cable to an available USB port on the computer or to an externally powered USB hub connected to the computer. Connect the other end of the USB 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 box closes, the installation is complete. The LED turns on after the device is successfully installed.

USB-1208FS-Plus User's Guide Installing the USB-1208FS-Plus

Caution! Do not disconnect any device from the USB bus while the computer is communicating with the

device, or you may lose data and/or your ability to communicate with the device.

If the LED turns off

If the LED is on but then turns off, the computer has lost communication with the device. To restore communication, disconnect the USB cable from the computer and then reconnect it. This should restore communication, and the LED should turn on.

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.

The USB-1208FS-Plus does not support field calibration.

# channels

scanned

Sample rate

(kS/s)

50 2 25 3 16.70

12.50 5 10 6 8.30 7 7.14 8 6.25

Chapter 3

Functional Details

Analog input acquisition modes

The USB-1208FS-Plus can acquire analog input data in either software paced or hardware paced mode.

Software paced

The USB-1208FS-Plus acquires data one analog sample at a time using software paced mode. You initiate the A/D conversion by calling a software command. The analog value is converted to digital and returned to the computer. You can repeat this procedure until you have the total number of samples that you want.

The maximum sample rate in software-paced mode is system-dependent.

Hardware paced

The USB-1208FS-Plus can acquire data from up to eight channels using hardware-paced mode. The analog data is acquired and converted to digital values until you stop the scan. Data is transferred in blocks of 32 samples 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 sample rate is an aggregate rate. The total sample rate for all channels cannot exceed 50 kS/s.

The following table lists the sample rate when scanning from one to eight channels.

Maximum per channel sample rate

You can start a hardware-paced scan with a software command. Optionally, hardware-paced scans can be delayed by an external hardware trigger event.

USB-1208FS-Plus User's Guide Functional Details

Screw terminal pins 21 to 40

Screw terminal pins 1 to 20

LED 4 USB connector

LED state

Indication

Steady green

The device is connected to a computer or external USB hub.

Blinks continuously

Data is being transferred.

External components

The external components – screw terminal banks, LED, and USB connector –are shown in Figure 2.

Figure 2. External components

USB connector

Receives the supplied USB cable. When connected to a computer or USB hub, the cable provides power and communication. No external power supply is required.

LED

The following table lists the behavior of the device LED.

Screw terminals

The screw terminals provide the following connections:

 Eight analog input connections (CH0 IN to CH7 IN, CH0 IN HI/LO through CH3 IN HI/LO)  Two analog output connections (D/A OUT 0 to D/A OUT 1)  16 digital I/O connections (PortA0 to Port A7, and Port B0 to Port B7)  External trigger input (TRIG_IN)  External counter input (CTR)  Bidirectional terminal for external clocking or multi-unit synchronization (SYNC)  Power output (+VO)  Analog ground (AGND) and ground (GND)

Use 16 AWG to 30 AWG wire when making connections to the screw terminals.

USB-1208FS-Plus User's Guide Functional Details

The single-ended mode pinout is shown in Figure 3.

Figure 3. Single-ended mode pinout

The differential mode pinout is shown in Figure 4.

Figure 4. Differential mode pinout

USB-1208FS-Plus User's Guide Functional Details

Signal connections

Analog input

You can connect up to eight analog input connections to the screw terminal bank containing pins 1 to 20. You can configure the analog input channels as eight single-ended channels (CH0 IN through CH7 IN) or four

differential channels (CH0 IN HI/LO through CH3 IN HI/LO). When configured for differential mode, each analog input has 12-bit resolution. When configured for single-ended mode, each analog input has 11-bit resolution, due to restrictions imposed by the A/D converter.

Single-ended configuration

When configured for single-ended input mode, the input signal is referenced to signal ground (GND) and delivered through two wires:

 Connect the wire carrying the signal to be measured to CH# IN.  Connect the second wire to AGND.

The input range for single-ended mode is ±10 V. The single-ended mode pinout is shown in Figure 3 on page

11.

Differential configuration

When configured for differential input mode, the input signal is measured with respect to the low input and delivered through three wires:

 Connect the wire carrying the signal to be measured to CH# IN HI.  Connect the wire carrying the reference signal to CH# IN LO.  Connect the third wire to GND.

The differential mode pinout is shown in Figure 4 on page 11.

Note: To perform a single-ended measurement using differential channels, connect the signal to CH# IN HI and

ground the associated CH# IN LO input. A low-noise precision programmable gain amplifier (PGA) is available on differential channels to provide gains

of up to 20 and a dynamic range of up to 12-bits. Differential mode input voltage ranges are ±20 V, ±10 V, ±5 V, ±4 V, ±2.5 V, ±2.0 V, ±1.25 V, and ±1.0 V.

In differential mode, the following two requirements must be met for linear operation:

 Any analog input must remain in the −10V to +20V range with respect to ground at all times.  The maximum differential voltage on any given analog input pair must remain within the selected voltage

range.

The input [common-mode voltage + signal] of the differential channel must be in the −10 V to +20 V range in order to yield a useful result.

USB-1208FS-Plus User's Guide Functional Details

For example, you input a 4 V pp sine wave to CH# IN HI, and apply the same sine wave 180° out of phase to CH# IN LO. The common mode voltage is 0 V. The differential input voltage swings from 4 V – (–4 V) = 8 V to –4 V – (4 V) = –8V. Both inputs satisfy the –10 V to +20 V input range requirement, and the differential voltage is suited for the ±10 V input range (see Figure 5).

Figure 5. Differential voltage example: common mode voltage of 0 V

If you increase the common mode voltage to 11 V, the differential remains at 8 V. Although the [common-mode voltage + signal] on each input now has a range of +7 V to +15 V, both inputs still satisfy the –10 V to +20 V

input requirement (see Figure 6).

Figure 6. Differential voltage example: common mode voltage of 11 V

If you decrease the common-mode voltage to –7 V, the differential stays at 8 V. However, the solution now violates the input range condition of –10 V to +20 V. The voltage on each analog input now swings from –3 V to –11 V. Voltages between –10 V and –3 V are resolved, but those below -10 V are clipped, as shown in Figure 7.

Figure 7. Differential voltage example: common mode voltage of –7 V

Since the analog inputs are restricted to a −10 V to +20 V signal swing with respect to ground, all ranges except ±20V can realize a linear output for any differential signal with zero common mode voltage and full scale signal inputs. The ±20 V range is the exception. You cannot put −20 V on CH# IN HI and 0 V on CH# IN LO, since this violates the input range criteria.

USB-1208FS-Plus User's Guide Functional Details

CH# IN HI

CH# IN LO

Result

–20 V

0 V

Invalid

–15 V

+5 V

Invalid

–10 V

0 V

–10 V

+10 V

–20 V

0 V

+10 V

–10 V

0 V

+20 V

–20 V

+10 V

–10 V

+20 V

+10 V

0 V

+10 V

+15 V

–5 V

+20 V

Element

Channel

Range

Gain

CH0

BIP10V

CH1

BIP20V

CH3

BIP4V

The table below shows some possible inputs and the expected results.

Sample inputs and differential results

For more information on analog signal connections

For more information on single-ended and differential 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 set up a scan sequence with a unique per-channel gain setting and channel sequence. The settings are stored in a channel-gain queue list that is written to local memory on the device. The gain queue can contain up to eight elements in single-ended mode, and up to four elements in differential mode.

The elements must be unique and listed in ascending order. An example of a three-element list is shown in the table below.

Sample channel-gain queue list

When a scan begins with the gain queue enabled, the device reads the first element, sets the appropriate channel number, range, and gain, and then acquires a sample. The properties of the next element are then retrieved, and another sample is acquired. This sequence continues until all elements in the gain queue have been selected.

When the end of the channel list is detected, the sequence returns to the first element in the list. The sequence repeats until the specified number of samples is acquired.

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.

For more information about analog signal connections

For more information about analog input connections, refer to the Guide to Signal Connections (this document is available on our web site at www.mccdaq.com/signals/signals.pdf).

Analog output

You can connect up to two analog output connections to D/A OUT 0 and D/A OUT 1. Each channel can be paced at rates up to 50,000 updates per second. The output range is 0 V to 5 V.

USB-1208FS-Plus User's Guide Functional Details

Digital I/O

The device has 16 DIO channels that are configured as two 8-bit ports – Port A and Port B. Port B is high drive. You can connect up to eight DIO lines to Port A0 to Port A7 and up to eight DIO lines to Port B0 to Port B7. You can configure each port for either input or output. The digital ports are set for input when the device is powered on or reset.

When configured for input, the digital I/O terminals can detect the state of any TTL-level. Refer to the schematic shown in Figure 8.

Figure 8. Schematic showing switch detection by digital channel Port A0

If you set the switch to the +5V input, Port A0 reads TRUE (1). When set to GND, Port A0 reads FALSE (0).

Pull-up/down configuration

All digital I/O lines are pulled high to USB +5 V with a 47 kΩ resistor by 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.

Complete the following steps to set the jumper for pull-up or pull-down:

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-1208FS-Plus 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. The user-configurable jumpers are labeled DIO A and DIO B. Figure 9 shows the location of each jumper on

the circuit board.

Figure 9. Pull-up/down jumper locations

5. Set each jumper for pull-up (P/UP) or pull-down (P/DN), as shown in Figure 10. Use the jumper labeled

DIO A to configure Port A, and DIO B to configure Port B.

USB-1208FS-Plus User's Guide Functional Details

Figure 10. 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 more information on 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 connection is input to the 32-bit external event. The internal counter increments when the TTL levels transition from low to high. The counter can count frequencies of up to 1 MHz.

External trigger input

The TRIG_IN connection is an external trigger input that you can configure for either rising or falling edge.

SYNC I/O

The SYNC terminal 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

terminal supports TTL-level input signals of up to 50 kHz.

 Configure as an output to pace the conversions on a second device and acquire data from 16 channels using

one clock. For more information about synchronized operations see page 19.

Power output

The +VO connection draws power from the USB connector on the computer. Caution! The +VO terminal is an output. Do not connect it to an external power supply or you may damage

the device and possibly the computer.

Ground

The analog ground (AGND) terminals provide a common ground for all analog channels. The digital ground (GND) terminals provide a common ground for the digital, trigger, counter, and sync

channels and the power terminal.

Accuracy

The overall accuracy of any instrument is limited by the error components within the system. Resolution is often incorrectly used to quantify the performance of a measurement product. While "12-bits" or "1 part in 4,096" does indicate what can be resolved, it provides little insight into the quality of an absolute measurement. Accuracy specifications describe the actual results that can be realized with a measurement device.

There are three types of errors which affect the accuracy of a measurement system:

 offset  gain  nonlinearity

The primary error sources are offset and gain. Nonlinearity is small in each device, and is not significant as an error source with respect to offset and gain.

USB-1208FS-Plus User's Guide Functional Details

Figure 11 shows an ideal, error-free transfer function. The typical calibrated accuracy is range-dependent. Refer to the "Accuracy specifications" on page 22 for more information. We use a ±10 V range here as an example of what you can expect when performing a measurement in this range.

Figure 11. Ideal ADC transfer function

The offset error is measured at mid-scale. Ideally, a zero volt input should produce an output code of 2048. Any deviation from this is an offset error.

Figure 12 shows an example of a transfer function with a ±9.77 mV offset error. 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 12 are drawn for clarity and are not drawn to scale.

Figure 12. ADC transfer function with offset error

USB-1208FS-Plus User's Guide Functional Details

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 13 shows the transfer function with gain error. Gain error is easily converted to voltage by multiplying the full-scale (FS) input by the error.

The accuracy plots in Figure 13 are drawn for clarity and are not drawn to scale.

Figure 13. ADC Transfer function with gain error

For example, the USB-1208FS-Plus exhibits a typical calibrated gain error of ±0.2% on all ranges. For the ±10 V range, this would yield 10 V × ±0.002 = ±20 mV. This means that at full scale, and neglecting the effect of offset, the measurement would be within 20 mV of the actual value. Note that gain error is expressed as a ratio. Values near ±FS 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 14, we have a plot of the error band for the ±10 V range. This is a graphical version of the typical accuracy specification of the product.

The accuracy plots in Figure 14 are drawn for clarity and are not drawn to scale.

Figure 14. Error band plot

USB-1208FS-Plus User's Guide Functional Details

Synchronized operations

You can connect the SYNC pin of two devices together in a master/slave configuration and acquire data from the analog inputs of both devices using one clock.

When the SYNC pin is configured as an output, the internal A/D pacer clock signal is sent to the screw terminal. Output the clock signal to the SYNC pin of a second device that is configured for A/D pacer input.

Power

Connecting the device to a computer draws <100 mA of current from the USB +5V supply. When running applications, the current that can be drawn from all device connections (analog, digital, SYNC, and +VO output loading) is <500 mA. The maximum output current that is available at the +VO power output terminal is 100 mA.

With all outputs at their maximum output current, the USB-1208FS-Plus in a fully-loaded configuration may be above that allowed by the computer. In this case, determine the per-pin loading in the application to ensure that the maximum loading criteria is met. The per-pin loading is calculated by dividing +5V by the load impedance of the pin in question.

USB-1208FS-Plus User's Guide Functional Details

Mechanical drawings

Figure 15. Circuit board (top) and enclosure dimensions

Parameter

Condition

Specification

A/D converter type

Successive approximation type

Input voltage range for linear operation

CHx to GND

Single-ended mode: ±10 V max Differential mode: –10 V min, +20 V max

Absolute maximum input voltage

CHx to GND

±28 V max

Input impedance

122 kΩ

Input current (Note 1)

Vin = +10 V

70 µA typ

Vin = 0 V

–12 µA typ

Vin = –10 V

–94 µA typ

Number of channels

8 single-ended or 4 differential; software-selectable

Input ranges

Single-ended

±10 V, G=2

Differential

±20 V, G=1 ±10 V, G=2 ±5 V, G=4 ±4 V, G=5 ±2.5 V, G=8 ±2.0 V, G=10 ±1.25 V, G=16 ±1.0 V, G=20 Software-selectable

Throughput (Note 2) Software paced

250 S/s typ, PC-dependent

Hardware paced

0.014 S/s to 50 kS/s

Channel gain queue

Software selectable. 8 elements in SE mode, 4 elements in DIFF mode.

One gain element per channel. Elements must be unique and listed in ascending order.

Resolution (Note 3) Differential

12 bits, no missing codes

Single-ended

11 bits

Integral linearity error

±1 LSB typ

Differential linearity error

±0.5 LSB typ

Repeatability

±1 LSB typ

Trigger source

Software-selectable

External digital: TRIG_IN Software-selectable

Pacer source

Software-selectable

 Internal  External (SYNC), rising edge triggered

Software-selectable

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. Analog input specifications

Chapter 4

Note 1: Input current is a function of applied voltage on the analog input channels. For a given input

Note 2: Maximum throughput when scanning is machine dependent. Note 3: The AD7870 converter only returns 11 bits (0 to 2,047 codes) in single-ended mode.

voltage, Vin, the input leakage is approximately equal to (8.181 * V

– 12) µA.

USB-1208FS-Plus User's Guide Specifications

Range

Accuracy (LSB)

±20 V

5.1

±10 V

6.1

±5 V

8.1

±4 V

9.1

±2.5 V

12.1

±2 V

14.1

±1.25 V

20.1

±1 V

24.1

Range

Accuracy (LSB)

±10 V

4.0

Range

% of Reading

Gain Error at FS (mV)

Offset (mV)

Accuracy at FS (mV)

±20 V

0.2

9.766

49.766

±10 V

0.2

9.766

29.766

±5 V

0.2

9.766

19.766

±4 V

0.2 8 9.766

17.766

±2.5 V

0.2 5 9.766

14.766

±2 V

0.2 4 9.766

13.766

±1.25 V

0.2

2.5

9.766

12.266

±1 V

0.2 2 9.766

11.766

Range

% of Reading

Gain Error at FS (mV)

Offset (mV)

Accuracy at FS (mV)

±10 V

0.2

19.531

39.531

Range

Typical counts

LSB

rms

±20 V

0.30

±10 V

0.30

±5 V

0.45

±4 V

0.45

±2.5 V

0.61

±2 V

0.76

±1.25 V

1.06

±1 V

1.21

Range

Typical counts

LSB

rms

±10 V

0.30

Accuracy

Table 2. Accuracy, differential mode

Table 3. Accuracy, single-ended mode

Table 4. Accuracy components, differential mode – all values are (±)

Table 5. Accuracy components, single-ended mode – all values are (±)

Noise performance

Table 6. Noise performance, differential mode

Table 7. Noise performance, single-ended mode

USB-1208FS-Plus User's Guide Specifications

Parameter

Condition

Specification

Resolution

12-bits, 1 in 4,096

Output range

0 V to 5.0 V

Number of channels

Throughput (Note 4) Software paced

250 S/s single channel typ, PC dependent

Hardware paced

50 kS/s max per channel

Power on and reset voltage

Initializes to 000h code

Output drive

Each D/A OUT

5 mA, sourcing

Slew rate

0.8 V/ µs typ

Range

Accuracy (LSB)

0 V to 5.0 V

4.0 typ, 45.0 max

Range

% of FSR

Gain Error at FS (mV)

Offset (mV)

(Note 5)

Accuracy at FS (mV)

0 V to 5.0 V

0.1 typ, 0.9 max

4.0 typ, 36.0 max

1.0 typ, 9.0 max

4.0 typ, 45.0 max

Parameter

Specification

Digital type

CMOS

Number of I/O

16 (Port A0 through A7, Port B0 through B7)

Configuration

2 banks of 8. Port B is high current drive.

Pull up/pull-down configuration

All pins pulled up to 5V via 47 kΩ resistors (default). Change to pull-down using internal user-configurable jumpers.

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, Port A

4.4 V min (IOH = –20 µA)

3.84 V min (IOH = –6.0 mA)

Output low voltage, Port A

0.1 V max (IOL = 20 µA)

0.33 V max (IOL = 6.0 mA)

Output high voltage, Port B

4.4 V min (IOH = –50 µA)

3.76 V min (IOH = –24.0 mA)

Output low voltage, Port B

0.1 V max (IOH = 50 µA)

0.44 V max (IOH = 24.0 mA)

Power on and reset state

Input

Analog output

Table 8. Analog output specifications

Note 4: Maximum throughput when scanning is machine dependent.

Table 9. Analog output accuracy, all values are (±); accuracy tested at no load

Table 10. Analog output accuracy components, all values are (±)

Note 5: Zero-scale offsets may result in a fixed zero-scale error producing a "dead-band” digital input code

region. In this case, changes in digital input code at values less than 0x040 may not produce a corresponding change in the output voltage. The offset error is tested and specified at code 0x040.

Digital input/output

Table 11. Digital I/O specifications

USB-1208FS-Plus User's Guide Specifications

Parameter

Specification

Trigger source (Note 7)

External digital; TRIG_IN terminal

Trigger mode

Edge sensitive; software-selectable for CMOS compatible rising or falling edge, high or low level.

Trigger latency

10 µs max

Trigger pulse width

1 µs 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

3.1 V 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

Parameter

Condition

Specification

Terminal name

SYNC

Terminal type

Bidirectional

Direction (software-selectable)

Output

Outputs the internal A/D pacer clock

Input (default)

Receives A/D pacer clock from external source

Input clock rate

50 kHz, max

Clock pulse width Input mode

1 µs min

Output mode

5 µs 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

3.1 V 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)

External trigger

Table 12. Digital trigger specifications

External clock input/output

Table 13. External clock I/O specifications

USB-1208FS-Plus User's Guide Specifications

Parameter

Specification

Pin name

CTR

Counter type

Event counter

Number of channels

Input type

Schmitt trigger, 47 kΩ pull-down to ground, rising edge triggered

Input source

CTR screw terminal

Resolution

32 bits

Maximum input frequency

1 MHz

High pulse width

500 ns min

Low pulse width

500 ns min

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

Non-volatile EEPROM

2,048 bytes (768 bytes calibration, 256 bytes user, 1,024 bytes DAQFlex)

Type

High performance 16-bit RISC microcontroller

Parameter

Condition

Specification

Supply current

During USB enumeration

< 100 mA

After USB enumeration, including DIO, AO, SYNC, and +VO output loading

< 500 mA +VO power available

After USB enumeration

4.5 V min, 5.25 V max

+VO output current

After USB enumeration

100 mA max

Counter

Table 14. Counter specifications

Memory

Microcontroller

Power

Table 15. Memory specifications

Table 16. Microcontroller specifications

Table 17. Power specifications

USB-1208FS-Plus User's Guide Specifications

Parameter

Specification

Device type

USB 2.0 full speed

Device compatibility

USB 1.1, USB 2.0

Parameter

Specification

Operating temperature range

0 °C to 70 °C

Storage temperature range

–40 °C to 70 °C

Humidity

0% to 90% non-condensing

Parameter

Specification

Dimensions (L × W × H)

79 × 82 × 27 mm (3.10 × 3.20 × 1.05 in.)

USB cable length

3 m (9.84 ft) max

User connection length

3 m (9.84 ft) max

Parameter

Specification

Connector type

Screw terminal

Wire gauge range

16 AWG to 30 AWG

General

Table 18. General specifications

Environmental

Table 19. Environmental specifications

Mechanical

Table 20. Mechanical specifications

Signal connector

Table 21. Screw terminal specifications

USB-1208FS-Plus User's Guide Specifications

Signal name

Pin description

Signal name

Pin description

CH0 IN HI

Analog input 0+

Port A0

Port A bit 0

CH0 IN LO

Analog input 0–

Port A1

Port A bit 1

AGND

Analog ground

Port A2

Port A bit 2

CH1 IN HI

Analog input 1+

Port A3

Port A bit 3

CH1 IN LO

Analog input 1–

Port A4

Port A bit 4

AGND

Analog ground

Port A5

Port A bit 5

CH2 IN HI

Analog input 2+

Port A6

Port A bit 6

CH2 IN LO

Analog input 2–

Port A7

Port A bit 7

AGND

Analog ground

GND

Ground

CH3 IN HI

Analog input 3+

+VO

Power output

CH3 IN LO

Analog input 3–

GND

Ground

AGND

Analog ground

Port B0

Port B bit 0

D/A OUT 0

Analog output 0

Port B1

Port B bit 1

D/A OUT 1

Analog output 1

Port B2

Port B bit 2

AGND

Analog ground

Port B3

Port B bit 3

Reserved

Reserved for future use

Port B4

Port B bit 4

GND

Ground

Port B5

Port B bit 5

TRIG_IN

Trigger input

Port B6

Port B bit 6

SYNC

Synchronization I/O

Port B7

Port B bit 7

CTR

Counter input

GND

Ground

Signal name

Pin description

Signal name

Pin description

CH0 IN

Analog input 0

Port A0

Port A bit 0

CH1 IN

Analog input 1

Port A1

Port A bit 1

AGND

Analog ground

Port A2

Port A bit 2

CH2 IN

Analog input 2

Port A3

Port A bit 3

CH3 IN

Analog input 3

Port A4

Port A bit 4

AGND

Analog ground

Port A5

Port A bit 5

CH4 IN

Analog input 4

Port A6

Port A bit 6

CH5 IN

Analog input 5

Port A7

Port A bit 7

AGND

Analog ground

GND

Ground

CH6 IN

Analog input 6

+VO

Power output

CH7 IN

Analog input 7

GND

Ground

AGND

Analog ground

Port B0

Port B bit 0

D/A OUT 0

Analog output 0

Port B1

Port B bit 1

D/A OUT 1

Analog output 1

Port B2

Port B bit 2

AGND

Analog ground

Port B3

Port B bit 3

Reserved

Reserved for future use

Port B4

Port B bit 4

GND

Ground

Port B5

Port B bit 5

TRIG_IN

Trigger input

Port B6

Port B bit 6

SYNC

Synchronization I/O

Port B7

Port B bit 7

CTR

Counter input

GND

Ground

Differential mode pinout

Table 22. 4-channel differential mode pinout

Single-ended mode pinout

Table 23. 8-channel single-ended mode pinout

Declaration of Conformity

Manufacturer: Measurement Computing Corporation Address: 10 Commerce Way Suite 1008 Norton, MA 02766 USA Category: Electrical equipment for measurement, control and laboratory use.

Measurement Computing Corporation declares under sole responsibility that the product

USB-1208FS-Plus

to which this declaration relates is in conformity with the relevant provisions of the following standards or other documents:

EC EMC Directive 2004/108/EC: General Requirements, EN 61326-1:2006 (IEC 61326-1:2005). Emissions:

 EN 55011 (2007) / CISPR 11(2003): Radiated emissions: Group 1, Class B  EN 55011 (2007) / CISPR 11(2003): Conducted emissions: Group 1, Class B

Immunity: EN 61326-1:2006, Table 3.

 IEC 61000-4-2 (2001): Electrostatic Discharge immunity.  IEC 61000-4-3 (2002): Radiated Electromagnetic Field immunity.  To maintain compliance to the standards of this declaration, the following conditions must be met.  The host computer, peripheral equipment, power sources, and expansion hardware must be CE

compliant.

 All I/O cables must be shielded, with the shields connected to ground.  I/O cables must be less than 3 meters (9.75 feet) in length.  The host computer must be properly grounded.  The host computer must be USB 2.0 compliant.  Equipment must be operated in a controlled electromagnetic environment as defined by Standards EN

61326-1:2006, or IEC 61326-1:2005.

Note: Data acquisition equipment may exhibit noise or increased offsets when exposed to high RF fields (>1V/m) or transients.

Declaration of Conformity based on tests conducted by Chomerics Test Services, Woburn, MA 01801, USA in May, 2012. Test records are outlined in Chomerics Test Report #EMI6102.12.

We hereby declare that the equipment specified conforms to the above Directives and Standards.

Carl Haapaoja, Director of Quality Assurance

Measurement Computing Corporation

10 Commerce Way

Suite 1008

Norton, Massachusetts 02766

(508) 946-5100

Fax: (508) 946-9500

E-mail: info@mccdaq.com

www.mccdaq.com

Measurement USB-1408FS User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

About this User's Guide

What you will learn from this user's guide

Conventions in this user's guide

Preface

Where to find more information

Introducing the USB-1208FS-Plus

Functional block diagram

Installing the USB-1208FS-Plus

What comes with your shipment?

Hardware

Software

Documentation

Unpacking

Installing the software

Installing the hardware

Calibrating the hardware

Functional Details

Analog input acquisition modes

Software paced

Hardware paced

External components

USB connector

Screw terminals

Signal connections

Analog input

Single-ended configuration

Differential configuration

Channel-Gain queue

Analog output

Digital I/O

Pull-up/down configuration

Counter input

External trigger input

SYNC I/O

Power output

Ground

Accuracy

Synchronized operations

Power

Mechanical drawings

Specifications

Analog input

Accuracy

Noise performance

Analog output

Digital input/output

External trigger

External clock input/output

Counter

Memory

Microcontroller

Power

General

Environmental

Mechanical

Signal connector

Differential mode pinout

Single-ended mode pinout

Declaration of Conformity