About UsNew Current Sense Amplifier with Integrated Low-Drift Shunt Resistor
TI’s New Design Offers Higher Accuracy and Reduced Board Footprint
Texas Instruments have introduced the industry’s first fully integrated first current-sense amplifier to integrate a high-precision, low-drift shunt resistor, which can deliver highly accurate measurements over a wide temperature range.
TI’s INA250 integrates the shunt resistor with a bi-directional, zero-drift current-sense amplifier to support both low-side and high-side implementations. Its accuracy and low drift reduce or may eliminate designers’ calibration effort for many systems. This integration also enables lower system cost and a smaller board footprint compared to competitive solutions.
By enabling high-accuracy measurement along with low system cost and a small board footprint, the INA250 current-sense amplifier delivers higher performance to applications such as test and measurement, communications load monitoring, and power supplies. Test and measurement designers can achieve required performance levels and potentially eliminate calibration while reducing cost up to 76 percent. High-performance enterprise and telecom equipment designers can achieve distributed measurement to maximize system efficiency and enhance system management.
Features of the INA250 Current Sense Amplifier include:
- Industry's most accurate integrated solution: The integrated 2-milliohm shunt resistor offers 0.1 percent tolerance as well as low drift of 15 ppm/°C
from -40°C to 125°C, enabling higher performance of the end equipment.
- The amplifier offers offset current of 12.5 mA with temperature drift of 250µA/°C and gain drift of 30 ppm/°C.
- The integrated packaging technology ensures an optimized Kelvin connection between the IC and the resistor.
- The amplifier enables a maximum error of 0.75 percent over the temperature range of -40°C to +125°C.
- Reduces system cost up to 76 percent and the board footprint up to 66 percent compared to competitive solutions by integrating the shunt resistor.
- Low power consumption: Maximum power consumption of 300µA minimizes the load that the measurement methodology adds to the system.
Technical Specifications of the INA250 Current Sense Amplifier
- Precision Integrated Shunt Resistor:
- Shunt Resistor: 2 mΩ
- Shunt Resistor Tolerance: 0.1% (Max)
- 15 A Continuous from –40°C to 85°C
- 0°C to 125°C Temperature Coefficient: 10 ppm/°C
- High Accuracy:
- Gain Error (Shunt and Amplifier): 0.3% (Max)
- Offset Current: 50 mA (Max, INA250A2)
- Four Available Gains:
- INA250A1: 200 mV/A
- INA250A2: 500 mV/A
- INA250A3: 800 mV/A
- INA250A4: 2 V/A
- Wide Common-Mode Range: –0.1 V to 36 V
- Specified Operating Temperature: –40°C to 125°C
The INA250 is currently available in a TSSOP16 Package and can be ordered from Texas Instruments in tube or tape and reel packaging.
More information on the INA250 Current Sense Amplifier, can be found on the TI website at TI INA250 product page
The Texas Instruments website address is www.ti.com
[Reprinted with kind permission from Texas Instruments]