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What are the transfer characteristics of the TL431 circuit?
TL431 Circuit: Comparator As shown in the figure, use the transfer characteristics of TL431 to form a practical voltage monitor. When the voltage is between the upper and lower limit voltages, the LED power and upper and lower limit voltages are (1+R1/R2)Vref and (1+R3/R4)Vref respectively.
How is the TL431 used in power supplies?
The TL431 is a “Programmable Precision Reference” and is commonly used in switching power supplies, where it provides feedback indicating if the output voltage is too high or too low. By using a special circuit called a bandgap, the TL431 provides a stable voltage reference across a wide temperature range.
How to calculate the voltage of a TL431 shunt regulator?
The formula to calculate output voltage is V = 2.5V * (1 + R13 / R12) TL431 Positive Voltage Regulator TL431 Negative Voltage Regulator LM317 TL431 Positive Voltage Regulator LM317 TL431 Negative Voltage Regulator
When does the TL431 trigger the V protection point?
As shown in the figure, when Vi exceeds a certain voltage, TL431 triggers. At this time, the thyristor is turned on and generates a large instantaneous current, which blows the fuse, thereby protecting the rear circuit. V protection point = (1+R1/R2)Vref. Figure 3. TL431 Circuit: Overvoltage Protection As the picture shows.
Is the TL431 an open loop operational amplifier?
On a functional level the TL431 contains a 2.5 V voltage reference, and an open-loop operational amplifier that compares the input control voltage with the reference. This, however, is merely an abstraction: both functions are inextricably linked inside the TL431’s front end.
What kind of capacitor is in the TL431?
A trimming fuse in the TL431. The TL431 contains two capacitors internally, and they are implemented in very different ways. The first capacitor (under the TLR431A text) is a is formed from a reverse-biased diode (the reddish and purple stripes).