HE100 level shifter circuit


I want to measure current of 0-50A. For that, in my application I am using HE100T01 hall effect sensor which can measure current from -100A to +100A(depending on the direction of flow it gives -ve and +ve values). The Hall effect sensor gives a current output of -50mA to +50mA. Since my micro controller ADC can't measure negative voltage, I tried level shifting the sensor output to positive region using the circuit which is attached. But the negative voltage is not properly clamping to the +2.5V offset. Can anyone please help me to identify the problem and also give any alternate circuitry to convert the sensor output which can be measured using a micro controller ADC?

Please find the datasheet for the Hall effect sensor and attached schematic. http://www.electrohms.com/data_pdf/2_1_HE100T01-05.pdf

Looking forward for earlier responses.


  • \$\begingroup\$ If your running a simulator, is C1 shorted? (see diagram) \$\endgroup\$
    – Nedd
    Nov 21, 2015 at 13:42
  • \$\begingroup\$ Thanks for the response. Its just a rough drawing of my circuit and it is already on the board. C1 is not shorted. its just a drawing mistake. \$\endgroup\$
    – Vishnu.P
    Nov 22, 2015 at 14:45

1 Answer 1


On most op-amps you cannot properly use an input signal that is below the - supply pin. You might try to bias the sensor output to 2.5v (with equal pull up and pull down resistors on the sensor's output).

Alternately, to set up a true level shifting circuit see these examples that use hall effect sensors:



  • \$\begingroup\$ Thanks a lot for the response. I'll try connecting as you suggested and let you know. I am currently using a 30E as burden resistor. Of what order of resistor value should I choose to bias the sensor output to 2.V? \$\endgroup\$
    – Vishnu.P
    Nov 22, 2015 at 14:49

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.