Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit Calculator

✖Emitter resistance base 1 is the resistance offered to the current flowing through the base 1 junction on UJT.ⓘ Emitter Resistance Base 1 [R_B1]			+10% -10%
✖Emitter Resistance Base 2 is the resistance offered to the current flowing through the base 2 junction on UJT.ⓘ Emitter Resistance Base 2 [R_B2]			+10% -10%

✖Intrinsic stand-off ratio UJT as Oscillator is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances.ⓘ Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit [η]

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Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit

Formula

`"η" = "R"_{"B1"}/("R"_{"B1"}+"R"_{"B2"})`

Example

`"0.529412"="18Ω"/("18Ω"+"16Ω")`

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Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit Solution

STEP 0: Pre-Calculation Summary

Formula Used

Intrinsic Stand-off Ratio = Emitter Resistance Base 1/(Emitter Resistance Base 1+Emitter Resistance Base 2)
η = R_B1/(R_B1+R_B2)
This formula uses 3 Variables

Variables Used

Intrinsic Stand-off Ratio - Intrinsic stand-off ratio UJT as Oscillator is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances.
Emitter Resistance Base 1 - (Measured in Ohm) - Emitter resistance base 1 is the resistance offered to the current flowing through the base 1 junction on UJT.
Emitter Resistance Base 2 - (Measured in Ohm) - Emitter Resistance Base 2 is the resistance offered to the current flowing through the base 2 junction on UJT.

STEP 1: Convert Input(s) to Base Unit

Emitter Resistance Base 1: 18 Ohm --> 18 Ohm No Conversion Required
Emitter Resistance Base 2: 16 Ohm --> 16 Ohm No Conversion Required

STEP 2: Evaluate Formula

Substituting Input Values in Formula

η = R_B1/(R_B1+R_B2) --> 18/(18+16)

Evaluating ... ...

η = 0.529411764705882

STEP 3: Convert Result to Output's Unit

0.529411764705882 --> No Conversion Required

FINAL ANSWER

0.529411764705882 ≈ 0.529412 <-- Intrinsic Stand-off Ratio

(Calculation completed in 00.004 seconds)

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Go Frequency = 1/(Stablizing Resistance*Capacitance*ln(1/(1-Intrinsic Stand-off Ratio)))

Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit

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Go Discharging Current = Input Voltage/((Resistance 1+Resistance 2))

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Go Emitter Current = (Emitter Voltage-Diode Voltage)/(Emitter Resistance Base 1+Emitter Resistance)

Circuit Turn off Time Class B Commutation

Go Circuit Turn Off Time Class B Commutation = Thyristor Commutation Capacitance*Thyristor Commutation Voltage/Load Current

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Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit

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Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit Formula

Intrinsic Stand-off Ratio = Emitter Resistance Base 1/(Emitter Resistance Base 1+Emitter Resistance Base 2)
η = R_B1/(R_B1+R_B2)

What is intrinsic stand-off ratio in UJT firing circuit?

For a unijunction transistor, the resistive ratio of RB1 to RBB is called the intrinsic stand-off ratio and is given the Greek symbol: η (eta). Typical standard values of η range from 0.5 to 0.8 for most common UJT’s.

If a small positive input voltage which is less than the voltage developed across resistance, RB1 ( ηVBB ) is now applied to the Emitter input terminal, the diode p-n junction is reverse biased, thus offering a very high impedance and the device does not conduct. The UJT is switched “OFF” and zero current flows.

How to Calculate Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit?

Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit calculator uses Intrinsic Stand-off Ratio = Emitter Resistance Base 1/(Emitter Resistance Base 1+Emitter Resistance Base 2) to calculate the Intrinsic Stand-off Ratio, The Intrinsic stand-off ratio for UJT based Thyristor firing circuit formula is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances. Intrinsic Stand-off Ratio is denoted by η symbol.

How to calculate Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit using this online calculator? To use this online calculator for Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit, enter Emitter Resistance Base 1 (R_B1) & Emitter Resistance Base 2 (R_B2) and hit the calculate button. Here is how the Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit calculation can be explained with given input values -> 0.529412 = 18/(18+16).

FAQ

What is Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit?

The Intrinsic stand-off ratio for UJT based Thyristor firing circuit formula is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances and is represented as η = R_B1/(R_B1+R_B2) or Intrinsic Stand-off Ratio = Emitter Resistance Base 1/(Emitter Resistance Base 1+Emitter Resistance Base 2). Emitter resistance base 1 is the resistance offered to the current flowing through the base 1 junction on UJT & Emitter Resistance Base 2 is the resistance offered to the current flowing through the base 2 junction on UJT.

How to calculate Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit?

The Intrinsic stand-off ratio for UJT based Thyristor firing circuit formula is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances is calculated using Intrinsic Stand-off Ratio = Emitter Resistance Base 1/(Emitter Resistance Base 1+Emitter Resistance Base 2). To calculate Intrinsic Stand-off Ratio for UJT based Thyristor Firing Circuit, you need Emitter Resistance Base 1 (R_B1) & Emitter Resistance Base 2 (R_B2). With our tool, you need to enter the respective value for Emitter Resistance Base 1 & Emitter Resistance Base 2 and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.

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