Guide: This article mainly introduces the principle of Hall switch, maybe many people have not heard of the Hall switch, but they want to be familiar with the Hall effect, let us learn how the Hall switch works. 1. Hall switch principle – Introduction to Hall Switch, also known as Hall digital circuit, is a new type of electrical accessory, a reverse voltage protector, precision voltage regulator, Hall voltage generator, differential The amplifier, Schmitt trigger, temperature compensator, and complementary set electrode open circuit outputs are composed of seven parts of the output, with no contact, low power, long service life, response frequency
Introduction: This article mainly introduces Hall switch principle, maybe many people have not heard Hall switch , but it is necessary to be familiar with Hall effect, let us Learn together Hall switch how to work.
Hall switch principle
Hall Switch, also known as Hall Digital circuit is a new type of electrical accessory, a reverse voltage protector, a precision voltage regulator, a Hall voltage generator, a differential amplifier, a Schmitt trigger, a temperature compensator, and a complementary collector open circuit output. Seven parts composition, have the characteristics of endless, low power, long service life, high response frequency, and the internal use of epoxy resin is into integrated, which can work reliably in various harsh environments. This circuit is due to a load capacity of up to 400 mA and is a complementary output, so it is the most ideal device for brushless fans.
Hall switch principle – structure
Hall The switching circuit consists of a reverse voltage protector, a precision voltage regulator, a Hall voltage generator, a differential amplifier, a Schmitt trigger, a temperature compensator, and a complementary set electrode opening output. Below we briefly introduce the features of each part.
Voltage Regulator: When the power supply voltage changes from 3.5V to 20V, the circuit is guaranteed normally.
Reverse protector: When the power supply is reversed or the interference of the reverse pulse voltage is used during use, the circuit protects the circuit, and the protection voltage can reach 30V.
Hall voltage generator: converts the changed magnetic signal into a corresponding electrical signal.
Differential amplifier: amplify the micro voltage signal output from the Hall voltage generator.
Schmitt trigger: will differentiateThe analog signal output from the amplifier is converted into a digital signal.
Temperature Compensator: Ensure that the integrated circuit is reliably operated between -20 ° C ~ + 85 ° C.
Complementary output: The output current can directly drive two sets of windings of the brushless fan.
As can be seen from the above, when the brush fan is turned on, if Hall The voltage generator is affected by an alternating magnetic field, and the potential state of the output 2 and 3 also changes, thereby changing the direction of the load current, so that the fan is operating normally.
3. Hall switch principle
The Hall effect is to be a metal or a metal or When the semiconductor sheet is placed vertically in the magnetic field, the two ends of the sheet generate potential difference, and the potential difference between the two ends is called the Hall potential u, which is:
u = kib In
The Hall coefficient, i is the current passed in the sheet, and B is the magnetic induction strength of the external magnetic field, and D is the thickness of the sheet.
The Hall switch belongs to an active magnetoelectric conversion device. On the basis of the principle of Hall effect, it makes it easy to convert magnetic input signals into practical applications. The electrical signal, while meeting the requirements of easy operation and reliability in the practical application of industrial applications.
Under the action of the magnetic field, when the magnetic induction strength exceeds the on-threshold BOP, the Hall circuit output pipe is conducted and outputs a low level. The B will then increase, and the circuit remains through-state. When the B value of the external magnetic field is reduced to BRP, the output tube is turned off and outputs a high level. We call BOP as a work point, BRP is released, and BOP-BRP = BH is called a return. The presence of a backgale makes the anti-interference ability of the switching circuit.
Xiaobian follow-up will continue to introduce the Hall switch in the work, if everyone is interested in,Continue to pay attention to us, the above is the introduction of the type of Hall switch and the Working principle of Hall switch.
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