US5881

Unipolar Hall Switch – Low Sensitivity

3901005881

Page 7 of 11

Data Sheet

Rev 007

Feb/06

12 Application Information

13 Application Comments

For proper operation, a 100nF bypass capacitor should be placed as close as possible to the device between

When using a resistor, three points are important:

When using a diode, a reverse current cannot flow and the voltage drop is almost constant (≈0.7V).

Therefore, a 100Ω/0.25W resistor for 5V application and a diode for higher supply voltage are recommended.

Both solutions provide the required reverse voltage protection.

When a weak power supply is used or when the device is intended to be used in noisy environment, it is

recommended that figure 13.3 from the Application Information section is used.

The low-pass filter formed by R1 and C1 and the zener diode Z1 bypass the disturbances or voltage spikes

12.1 Typical Three-Wire Application Circuit

12.3 Automotive and Harsh, Noisy Environments

Three-Wire Circuit

12.2 Two-Wire Circuit

Note:

With this circuit, precise ON and OFF

currents can be detected using only

two connecting wires.

The resistors RL and Rb can be used

to bias the input current. Refer to the

part specifications for limiting values.