MC USB-234-OEM User Manual Download Page 22

USB-234-OEM User's Guide 

Specifications 

22 

Digital input 

Table 5. Digital input specifications 

Parameter 

Condition 

Specification 

Input voltage range 

Power on 

0 V to 5 V 

Power off 

0 V to 3.3 V (Note 1) 

Input voltage protection 

 

±

20 V on two lines per port (maximum of five 

lines for all ports) for up to 24 hours 

Input high voltage 

 

2.3 V min 

Input low voltage 

 

0.8 V max 

Input leakage current 

At 3.3 V 

0.8 mA max 

At 5 V 

4.5 mA max 

Note 1:  

Do not leave a voltage above 3.3 V connected on the DIO line when the device is not powered. This can cause 

long-term reliability issues. 

Digital output 

Table 6. Digital output specifications 

Parameter 

Condition 

Specification 

Output low voltage

 

 

4 mA 

0.7 V max 

1 mA 

0.2 V max 

Output high voltage 

4 mA 

2.1 V min 

1 mA 

2.8 V min 

 

3.6 V max 

Maximum output current per 

line 

 

±

4 mA 

External digital trigger 

Table 6. External digital trigger specifications 

Parameter 

Specification 

Trigger source 

TRIG input 

Trigger mode 

Software configurable for rising or falling edge. Power on default is rising edge. 

Input high voltage 

2.3 V min 

Input low voltage 

0.8 V max 

Counter 

Table 7. Counter specifications 

Parameter 

Specification 

Pin name 

CTR 

Number of counters  

Resolution  

32 bits 

Counter type 

Edge counter (rising)  

Counter direction 

Count up 

Counter source  

CTR  

Input frequency 

5 MHz max 

High pulse width 

100 ns min 

Low pulse width  

100 ns min 

Summary of Contents for USB-234-OEM

Page 1: ...USB 234 OEM Analog and Digital I O User s Guide January 2019 Rev 4 Measurement Computing Corporation...

Page 2: ...d 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 Corporati...

Page 3: ...tails 9 Analog input acquisition modes 9 Software paced mode 9 Hardware paced mode 9 Board components 10 USB connector 10 Header connector J2 10 Signal connections 11 Analog input 11 Analog output 13...

Page 4: ...USB 234 OEM User s Guide 4 Power output 23 USB specifications 23 Environmental 24 Mechanical 24 Header connectors 24 Differential mode pinout 24 Single ended mode pinout 25...

Page 5: ...f 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 inf...

Page 6: ...ed device that is compatible with USB 3 0 ports The device is also compatible with USB 1 1 ports but use with this older hardware is not recommended due to longer initialization times that can occur w...

Page 7: ...USB 234 OEM User s Guide Introducing the USB 234 OEM 7 Functional block diagram Device functions are illustrated in the block diagram shown here Figure 1 USB 234 OEM functional block diagram...

Page 8: ...on a Windows platform Connect the USB 234 OEM to a to an available USB port on the computer running Windows Connect the other end of the cable to the micro USB connector on the device No external powe...

Page 9: ...mode You can acquire data from up to eight channels in hardware paced mode The analog data is continuously acquired and converted to digital values until you stop the scan Data is transferred in bloc...

Page 10: ...Do not connect to connector pins labeled NC J2 differential pinout Pin Signal name Pin description Pin Signal name Pin description 1 AOUT0 Analog output 0 2 AOUT1 Analog output 1 3 AGND Analog ground...

Page 11: ...O6 DIO bit 6 27 DIO7 DIO bit 7 28 NC No connection 29 TRIG Digital trigger input 30 NC No connection 31 NC No connection 32 GND Digital ground 33 CTR Counter input 34 VO User voltage output Signal con...

Page 12: ...ion 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 carr...

Page 13: ...e no longer than 0 5 m 20 in Avoid scanning faster than necessary Design your system to scan at slower speeds to give the DAQ device more time to settle to a more accurate level when switching between...

Page 14: ...a separate command to the hardware to initiate each DAQ conversion Software paced generations are also referred to as immediate or static operations They are typically used for writing a single value...

Page 15: ...ng is not liable for any damage resulting from such signal connections Power on states At system startup and reset the USB 234 OEM sets all DIO lines to high impedance inputs The device does not drive...

Page 16: ...USB 234 OEM to the USB host through the 34 pin connector do not connect to the USB connector Status LED driver LED The LED signal indicates the device status as shown in the following table LED State...

Page 17: ...ce Regulated 5 V supply 5 V Protection Circuit for overvoltage over current and short circuit protection The 5 V source is limited at 200 mA typically In case of hard short circuit to ground this limi...

Page 18: ...st connected to the USB connector or when the device is in suspend mode Ground The analog ground AGND connectors provide a common ground for all analog channels The digital ground GND connectors provi...

Page 19: ...USB 234 OEM User s Guide Functional Details 19 Mechanical drawings Figure 12 Circuit board dimensions...

Page 20: ...100 kS s Number of channels 8 single ended or 4 differential software selectable Input voltage range 10 V Working voltage 10 V Overvoltage protection Power on 30 V max Power off 20 V max Input impedan...

Page 21: ...re full scale 32 mV INL 4 LSB DNL 16 bits no missing codes Power on state 0 V Startup glitch 7 V for 10 s Timebase The following specifications apply to hardware paced analog input and analog output s...

Page 22: ...utput Table 6 Digital output specifications Parameter Condition Specification Output low voltage 4 mA 0 7 V max 1 mA 0 2 V max Output high voltage 4 mA 2 1 V min 1 mA 2 8 V min 3 6 V max Maximum outpu...

Page 23: ...ent 165 mA Maximum load USB current 500 mA Note 3 Note 2 A typical bus powered hub provides 100 mA on its USB lines The USB 234 OEM does not work on a bus powered hub Note 3 The maximum power draw fro...

Page 24: ...connector pins labeled NC Table 16 J2 differential pinout Pin Signal name Pin description Pin Signal name Pin description 1 AOUT0 Analog output 0 2 AOUT1 Analog output 1 3 AGND Analog ground 4 AGND A...

Page 25: ...nput 6 9 CH1H Analog input 1 10 CH1L Analog input 5 11 CH0H Analog input 0 12 CH0L Analog input 4 13 AGND Analog ground 14 AGND Analog ground 15 D USB differential data signals 16 VBUS USB power 17 D...

Page 26: ...ion NI Hungary Kft 10 Commerce Way H 4031 Debrecen H tar t 1 A Hungary Norton Massachusetts 02766 Phone 36 52 515400 508 946 5100 Fax 36 52 515414 Fax 508 946 9500 http hungary ni com debrecen E mail...

Reviews: