NI USB-7845R Specifications
- Updated2023-02-20
- 10 minute(s) read
NI USB-7845R Specifications
The following specifications are typical at 25 °C unless otherwise noted.
Analog Input
Number of channels | 8 | ||||||
Input modes | DIFF, NRSE, RSE (software-selectable; selection applies to all channels) | ||||||
Type of ADC | Successive approximation register (SAR) | ||||||
Resolution | 16 bits | ||||||
Conversion time | 2 µs | ||||||
Maximum sampling rate | 500 kS/s (per channel) | ||||||
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Input signal range | ±1 V, ±2 V, ±5 V, ±10 V (software-selectable) | ||||||
Input bias current | ±5 nA | ||||||
Input offset current | ±5 nA | ||||||
Input coupling | DC | ||||||
|
Range | Measurement Voltage, AI+ to AI- | Maximum Working Voltage (Signal + Common Mode) | ||
---|---|---|---|---|
Minimum (V)[1] | Typical (V) | Maximum (V) | ||
±10 V | ±10.37 | ±10.5 | ±10.63 | ±12 V of ground |
±5 V | ±5.18 | ± 5.25 | ±5.32 | ±10 V of ground |
±2 V | ±2.07 | ±2.1 | ±2.13 | ±8.5 V of ground |
±1 V | ±1.03 | ±1.05 | ±1.06 | ±8 V of ground |
AI Absolute Accuracy
Absolute accuracy at full scale numbers is valid immediately following internal calibration and assumes the device is operating within 10 °C of the last external calibration. Accuracies listed are valid for up to one year from the device external calibration.
- TempChangeFromLastExternalCal = 10 °C
- TempChangeFromLastInternalCal = 1 °C
- number_of_readings = 10,000
- CoverageFactor = 3 σ
Specifications | Range | |||
---|---|---|---|---|
±10 V | ±5 V | ±2 V | ±1 V | |
Residual Gain Error (ppm of Reading) | 104.4 | 105.9 | 110.6 | 118.4 |
Gain Tempco (ppm/°C) | 20 | 20 | 20 | 20 |
Reference Tempco (ppm/°C) | 4 | 4 | 4 | 4 |
Residual Offset Error (ppm of Range) | 16.4 | 16.4 | 16.4 | 16.4 |
Offset Tempco (ppm of Range/°C) | 4.18 | 4.17 | 4.41 | 4.63 |
INL Error (ppm of range) | 42.52 | 46.52 | 46.52 | 50.52 |
Random Noise, σ (µVrms) | 263 | 156 | 90 | 74 |
Absolute Accuracy at Full Scale (µV) | 2,283 | 1,170 | 479 | 252 |
Specifications | Range | |||
---|---|---|---|---|
±10 V | ±5 V | ±2 V | ±1 V | |
Residual Gain Error (ppm of Reading) | 2,921 | 3,021 | 3,021 | 3,021 |
Gain Tempco (ppm/°C) | 20 | 20 | 20 | 20 |
Reference Tempco (ppm/°C) | 4 | 4 | 4 | 4 |
Residual Offset Error (ppm of Range) | 661 | 671 | 700 | 631 |
Offset Tempco (ppm of Range/°C) | 4.18 | 4.17 | 4.41 | 4.63 |
INL Error (ppm of range) | 42.52 | 46.52 | 46.52 | 50.52 |
Random Noise, σ (µVrms) | 263 | 156 | 90 | 74 |
Absolute Accuracy at Full Scale (µV) | 36,895 | 19,018 | 7,667 | 3,769 |
Calculating Absolute Accuracy
Refer to the following equation for an example of calculating absolute accuracy for a 10 V reading.
- TempChangeFromLastExternalCal = 10 °C
- TempChangeFromLastInternalCal = 1 °C
- number_of_readings = 10,000
- CoverageFactor = 3 σ
DC Transfer Characteristics
INL | Refer to the AI Accuracy Table |
DNL | ±0.4 LSB typical, ±0.9 LSB maximum |
No missing codes | 16 bits guaranteed |
CMRR, DC to 60 Hz | -100 dB |
Dynamic Characteristics
|
Range (V) | Step Size (V) | Accuracy | ||
---|---|---|---|---|
±16 LSB | ±4 LSB | ±2 LSB | ||
±10 | ±20.0 | 1.50 µs | 4.00 µs | 7.00 µs |
±2.0 | 0.50 µs | 0.50 µs | 1.00 µs | |
±0.2 | 0.50 µs | 0.50 µs | 0.50 µs | |
±5 | ±10 | 1.50 µs | 3.50 µs | 7.50 µs |
±1 | 0.50 µs | 0.50 µs | 1.00 µs | |
±0.1 | 0.50 µs | 0.50 µs | 0.50 µs | |
±2 | ±4 | 1.00 µs | 3.50 µs | 8.00 µs |
±0.4 | 0.50 µs | 0.50 µs | 1.00 µs | |
±0.04 | 0.50 µs | 0.50 µs | 0.50 µs | |
±1 | ±2 | 1.00 µs | 3.50 µs | 12.00 µs |
±0.2 | 0.50 µs | 0.50 µs | 2.00 µs | |
±0.02 | 0.50 µs | 0.50 µs | 0.50 µs |
Crosstalk | -80 dB, DC to 100 kHz |
Analog Output
Output type | Single-ended, voltage output | ||||||
Number of channels | 8 | ||||||
Resolution | 16 bits | ||||||
Update time | 1.0 µs | ||||||
Maximum update rate | 1 MS/s | ||||||
Type of DAC | Enhanced R-2R | ||||||
Range | ±10 V | ||||||
Output coupling | DC | ||||||
Output impedance | 0.5 Ω | ||||||
Current drive | ±2.5 mA | ||||||
Protection | Short circuit to ground | ||||||
| |||||||
Power-on state | User-configurable | ||||||
Power-on glitch | -1 V for 1 µs |
Range | Measurement Voltage, AO+ to AO GND | ||
---|---|---|---|
Minimum (V)[2] | Typical (V) | Maximum (V) | |
±10 V | ±10.1 | ±10.16 | ±10.22 |
AO Absolute Accuracy
Absolute accuracy at full scale numbers is valid immediately following internal calibration and assumes the device is operating within 10 °C of the last external calibration. Accuracies listed are valid for up to one year from the device external calibration.
- TempChangeFromLastExternalCal = 10 °C
- TempChangeFromLastInternalCal = 1 °C
Specifications | ±10 V Range |
---|---|
Residual Gain Error (ppm of Reading) | 87.3 |
Gain Tempco (ppm/°C) | 12.6 |
Reference Tempco (ppm/°C) | 4 |
Residual Offset Error (ppm of Range) | 41.1 |
Offset Tempco (ppm of Range/°C) | 7.8 |
INL Error (ppm of range) | 61 |
Absolute Accuracy at Full Scale (µV) | 2,498 |
Specifications | ±10 V Range |
---|---|
Residual Gain Error (ppm of Reading) | 2,968.6 |
Gain Tempco (ppm/°C) | 12.6 |
Reference Tempco (ppm/°C) | 4 |
Residual Offset Error (ppm of Range) | 1,004.1 |
Offset Tempco (ppm of Range/°C) | 7.8 |
INL Error (ppm of range) | 61 |
Absolute Accuracy at Full Scale (µV) | 40,941 |
Calculating Absolute Accuracy
Refer to the following equation for an example of calculating absolute accuracy for a 10 V reading.
- TempChangeFromLastExternalCal = 10 °C
- TempChangeFromLastInternalCal = 1 °C
DC Transfer Characteristics
INL | Refer to the AO Accuracy Table |
DNL | ±0.5 LSB typical, ±1 LSB maximum |
Monotonicity | 16 bits, guaranteed |
Dynamic Characteristics
Step Size | Accuracy | ||
---|---|---|---|
±16 LSB | ±4 LSB | ±2 LSB | |
±20.0 V | 5.3 µs | 6.5 µs | 7.8 µs |
±2.0 | 3.2 µs | 3.9 µs | 4.4 µs |
±0.2 | 1.8 µs | 2.8 µs | 3.8 µs |
Slew rate | 10 V/µs |
Noise | 250 µVrms, DC to 1 MHz |
Glitch energy at midscale transition | ±10 mV for 3 µs |
5V Output
Output voltage | 4.75 V to 5.1 V |
Output current | 0.5 A maximum |
Overvoltage protection | ±30 V |
Overcurrent protection | 650 mA |
Digital I/O
Connector | Number of Channels | Maximum Frequency |
---|---|---|
Connector 0 | 32 | 80 MHz |
Connector 1 | 16 | 10 MHz |
Compatibility | LVTTL, LVCMOS |
Logic family | User-selectable |
Default software setting | 3.3 V |
Logic Family | Input Low Voltage | Input High Voltage |
---|---|---|
VIL (Maximum) | VIH (Minimum) | |
1.2 V | 0.42 V | 0.84 V |
1.5 V | 0.51 V | 1.01 V |
1.8 V | 0.61 V | 1.21 V |
2.5 V | 0.70 V | 1.60 V |
3.3 V | 0.80 V | 2.00 V |
Maximum input | 3.6 V |
Logic Family | Current | Output Low Voltage | Output High Voltage |
---|---|---|---|
VOL (Maximum) | VOH (Minimum) | ||
1.2 V | 100 µA | 0.20 V | 1.00 V |
1.5 V | 100 µA | 0.20 V | 1.25 V |
1.8 V | 100 µA | 0.20 V | 1.54 V |
2.5 V | 100 µA | 0.20 V | 2.22 V |
3.3 V | 100 µA, | 0.20 V, | 3.00 V, |
4 mA | 0.40 V | 2.40 V |
| |||||||
Input leakage current | ±15 µA maximum | ||||||
Input impedance | 50 kΩ typical, pull-down | ||||||
Output impedance | 50 Ω | ||||||
Power-on state | Programmable, by line | ||||||
Protection | ±20 V, single line | ||||||
Digital I/O voltage switching time | 2 ms maximum |
Reconfigurable FPGA
FPGA type | Kintex-7 70T |
Number of flip-flops | 82,000 |
Number of LUTs | 41,000 |
Embedded block RAM | 4,860 kbits |
Number of DSP48 slices | 240 |
Timebase | 40 MHz, 80 MHz, 120 MHz, 160 MHz, or 200 MHz |
Timebase accuracy, onboard clock | ±100 ppm |
Bus Interface
USB compatibility | USB 2.0 Hi-Speed or Full-Speed[3] |
Data transfers | DMA, interrupts, programmed I/O |
Number of DMA channels | 3 |
Power Requirement
Input voltage | 9 V to 30 V |
Maximum power | 20 W |
Overvoltage protection | 40 V |
Physical Characteristics
Dimensions | 18.5 cm × 17.3 cm × 3.6 cm (7.3 in. × 6.8 in. × 1.4 in.) |
Weight | 1,000 g (35.27 oz) |
I/O connectors | 2 × 68-pin VHDCI |
Safety Voltages
Connect only voltages that are below these limits.
Channel-to-earth | ±12 V, Measurement Category I |
Channel-to-channel | ±24 V, Measurement Category I |
Measurement Category I is for measurements performed on circuits not directly connected to the electrical distribution system referred to as MAINS voltage. MAINS is a hazardous live electrical supply system that powers equipment. This category is for measurements of voltages from specially protected secondary circuits. Such voltage measurements include signal levels, special equipment, limited-energy parts of equipment, circuits powered by regulated low-voltage sources, and electronics.
Safety Compliance Standards
This product is designed to meet the requirements of the following electrical equipment safety standards for measurement, control, and laboratory use:
- IEC 61010-1, EN 61010-1
- UL 61010-1, CSA C22.2 No. 61010-1
Electromagnetic Compatibility
CE Compliance
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This product meets the essential requirements of applicable European Directives, as follows:
- 2014/35/EU; Low-Voltage Directive (safety)
- 2014/30/EU; Electromagnetic Compatibility Directive (EMC)
- 2011/65/EU; Restriction of Hazardous Substances (RoHS)
- 2014/53/EU; Radio Equipment Directive (RED)
- 2014/34/EU; Potentially Explosive Atmospheres (ATEX)
Product Certifications and Declarations
Refer to the product Declaration of Conformity (DoC) for additional regulatory compliance information. To obtain product certifications and the DoC for NI products, visit ni.com/product-certifications, search by model number, and click the appropriate link.
Environmental
Refer to the manual for the chassis you are using for more information about meeting these specifications.
Operating temperature (IEC 60068-2-1, IEC 60068-2-2) | -40 °C to 70 °C |
Storage temperature (IEC 60068-2-1, IEC 60068-2-2) | -40 °C to 85 °C |
Operating humidity (IEC 60068-2-78) | 10% RH to 90% RH, noncondensing |
Storage humidity (IEC 60068-2-78) | 5% RH to 95% RH, noncondensing |
Pollution Degree | 2 |
Maximum altitude | 2,000 m |
Indoor use only.
Environmental Management
NI is committed to designing and manufacturing products in an environmentally responsible manner. NI recognizes that eliminating certain hazardous substances from our products is beneficial to the environment and to NI customers.
For additional environmental information, refer to the Engineering a Healthy Planet web page at ni.com/environment. This page contains the environmental regulations and directives with which NI complies, as well as other environmental information not included in this document.
EU and UK Customers
电子信息产品污染控制管理办法(中国RoHS)
Calibration
Recommended warm-up time | 15 minutes | ||||||||
Calibration interval | 1 year | ||||||||
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Worldwide Support and Services
Visit ni.com/support to find support resources including documentation, downloads, and troubleshooting and application development self-help such as tutorials and examples.
Visit ni.com/services to learn about NI service offerings such as calibration options, repair, and replacement.
Visit ni.com/register to register your NI product. Product registration facilitates technical support and ensures that you receive important information updates from NI.
NI corporate headquarters is located at 11500 N Mopac Expwy, Austin, TX, 78759-3504, USA.
1 The minimum measurement voltage range is the largest voltage the NI USB-7845R is guaranteed to accurately measure.
2 The minimum measurement voltage range is the largest voltage the NI USB-7845R is guaranteed to accurately measure.
3 Operating on a full-speed bus will result in lower performance and you might not be able to achieve maximum sampling/update rates.
4 Actual value stored in Flash memory
In This Section
- Analog Input
- Analog Output
- Digital I/O
- Reconfigurable FPGA
- Bus Interface
- Power Requirement
- Physical Characteristics
- Safety Voltages
- Safety Compliance Standards
- Electromagnetic Compatibility
- CE Compliance
- Product Certifications and Declarations
- Environmental
- Environmental Management
- Calibration
- Worldwide Support and Services