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## Emitter current for UJT based Thyristor firing circuit Solution

STEP 0: Pre-Calculation Summary
Formula Used
Emitter current = (Emitter Voltage-Diode voltage)/(Emitter resistance base 1+Emitter Resistance)
Ie = (VE-VD)/(RB1+re)
This formula uses 4 Variables
Variables Used
Emitter Voltage - Emitter Voltage is defined as the voltage across the emitter terminal of any transistor device. (Measured in Volt)
Diode voltage - Diode voltage is defined as the voltage developed across diode when it is in on state. (Measured in Volt)
Emitter resistance base 1 - Emitter resistance base 1 is the resistance offered to the current flowing through the base 1 junction on UJT. (Measured in Ohm)
Emitter Resistance - Emitter Resistance is a dynamic resistance of the emitter-base junction diode of a transistor. (Measured in Ohm)
STEP 1: Convert Input(s) to Base Unit
Emitter Voltage: 10 Volt --> 10 Volt No Conversion Required
Diode voltage: 5 Volt --> 5 Volt No Conversion Required
Emitter resistance base 1: 10 Ohm --> 10 Ohm No Conversion Required
Emitter Resistance: 50 Ohm --> 50 Ohm No Conversion Required
STEP 2: Evaluate Formula
Substituting Input Values in Formula
Ie = (VE-VD)/(RB1+re) --> (10-5)/(10+50)
Evaluating ... ...
Ie = 0.0833333333333333
STEP 3: Convert Result to Output's Unit
0.0833333333333333 Ampere --> No Conversion Required
0.0833333333333333 Ampere <-- Emitter current
(Calculation completed in 00.016 seconds)

## < 10+ Thyristors Calculators

Excess work due to thyristor 1 in chopper circuit
Excess energy in chopper circuit = 0.5*Reverse di/dt limiting inductance*((Load current of chopper circuit+(Reverse recovery time*Commutation capacitor voltage)/Reverse di/dt limiting inductance)-(Load current of chopper circuit^2)) Go
Worst case steady state voltage across first thyristor in series connected thyristors
Worst case steady state voltage of thyristor 1 = ((Resultant series voltage of thyristor string+(Number of thyristors in series thyristor string-1)*Resistance*Off state current spread of thyristor string))/Number of thyristors in series thyristor string Go
Voltage across first thyristor in series-connected thyristors
Voltage across thyristor 1 in thyristor string = (Resultant series voltage of thyristor string+(Number of thyristors in series thyristor string-1)*Resistance*Off state current spread of thyristor string)/Number of thyristors in series thyristor string Go
Resultant series voltage of series connected thyristor string
Resultant series voltage of thyristor string = Number of thyristors in series thyristor string*Voltage across thyristor 1 in thyristor string-(Number of thyristors in series thyristor string-1)*Resistance*Off state current spread of thyristor string Go
Maximum Thyristor gate voltage for resistance firing circuit
Maximum gate voltage = Maximum AC input voltage*(Stabilizing Resistance/(Stabilizing Resistance+Variable Resistance+Resistance)) Go
Derating factor of series connected thyristor string
Derating factor of thyristor string = 1-(Resultant series voltage of thyristor string/(Number of thyristors in series thyristor string*Worst case steady state voltage of thyristor 1)) Go
Power dissipated by heat in SCR
Power dissipated by heat in SCR = (SCR junction temperature-SCR ambient temperature)/Thermal resistance of SCR Go
Thermal resistance of SCR
Thermal resistance of SCR = (SCR junction temperature-SCR ambient temperature)/Power dissipated by heat in SCR Go
Leakage current of the collector-base junction
Collector to base leakage current = Collector current-Common base current gain of transistor*Emitter current Go
Discharging current of dv/dt protection thyristor circuits
Discharging current of thyristor circuit = Input voltage/((Resistance+Resistance)) Go

### Emitter current for UJT based Thyristor firing circuit Formula

Emitter current = (Emitter Voltage-Diode voltage)/(Emitter resistance base 1+Emitter Resistance)
Ie = (VE-VD)/(RB1+re)

## Discuss the applications of UJT?

The most common application of a unijunction transistor is as a triggering device for SCR’s and Triacs but other UJT applications include sawtoothed generators, simple oscillators, phase control, and timing circuits. The simplest of all UJT circuits is the Relaxation Oscillator producing non-sinusoidal waveforms.

In a basic and typical UJT relaxation oscillator circuit, the Emitter terminal of the UJT is connected to the junction of a series connected resistor and capacitor, RC circuit as shown below.

## How to Calculate Emitter current for UJT based Thyristor firing circuit?

Emitter current for UJT based Thyristor firing circuit calculator uses Emitter current = (Emitter Voltage-Diode voltage)/(Emitter resistance base 1+Emitter Resistance) to calculate the Emitter current, The Emitter current for UJT based Thyristor firing circuit formula is defined as the magnitude of the current that flows through the emitter when it is in conducting mode. Emitter current is denoted by Ie symbol.

How to calculate Emitter current for UJT based Thyristor firing circuit using this online calculator? To use this online calculator for Emitter current for UJT based Thyristor firing circuit, enter Emitter Voltage (VE), Diode voltage (VD), Emitter resistance base 1 (RB1) & Emitter Resistance (re) and hit the calculate button. Here is how the Emitter current for UJT based Thyristor firing circuit calculation can be explained with given input values -> 0.083333 = (10-5)/(10+50).

### FAQ

What is Emitter current for UJT based Thyristor firing circuit?
The Emitter current for UJT based Thyristor firing circuit formula is defined as the magnitude of the current that flows through the emitter when it is in conducting mode and is represented as Ie = (VE-VD)/(RB1+re) or Emitter current = (Emitter Voltage-Diode voltage)/(Emitter resistance base 1+Emitter Resistance). Emitter Voltage is defined as the voltage across the emitter terminal of any transistor device, Diode voltage is defined as the voltage developed across diode when it is in on state, Emitter resistance base 1 is the resistance offered to the current flowing through the base 1 junction on UJT & Emitter Resistance is a dynamic resistance of the emitter-base junction diode of a transistor.
How to calculate Emitter current for UJT based Thyristor firing circuit?
The Emitter current for UJT based Thyristor firing circuit formula is defined as the magnitude of the current that flows through the emitter when it is in conducting mode is calculated using Emitter current = (Emitter Voltage-Diode voltage)/(Emitter resistance base 1+Emitter Resistance). To calculate Emitter current for UJT based Thyristor firing circuit, you need Emitter Voltage (VE), Diode voltage (VD), Emitter resistance base 1 (RB1) & Emitter Resistance (re). With our tool, you need to enter the respective value for Emitter Voltage, Diode voltage, Emitter resistance base 1 & Emitter Resistance and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well. Let Others Know