Contents
How do you find resistance without current?
If you know these two values, you can combine two formulas to solve for resistance:
- P = VI (power = voltage x current)
- Ohm’s Law tells us that V = IR.
- Substitute IR for V in the first formula: P = (IR)I = I2R.
- Rearrange to solve for resistance: R = P / I2.
Why do we connect a resistor directly to the base of the transistor?
A fairly simple stability technique is to add a resistor between emitter and ground in a BJT transistor operating in the CE mode. So, these resistors attached to the transistor in a basic amplifier circuit are for providing biasing and stability.
How to calculate V CE of a transistor?
V CE, the voltage that falls across the collector-emitter junction of a bipolar junction transistor, is a crucial voltage to DC analysis of a transistor circuit because it is the voltage that determines the load line and Q-point of a transistor. V CE is calculated by the formula below:
How to calculate base resistance of a transistor?
Therefore, with simple transposition of the above formula, the following formula provides the base resistance: Rb = (Vi – Vbe) / Ib. To guarantee that the transistor operates in the saturation region, we multiply the base current by a factor of three.
What kind of resistor do I need for a switching calculator?
For switching applications, a ¼-watt resistor with 5-% tolerance usually works fine. In order to use this calculator, you will need to know the input switching voltage (Vi), supply voltage Vcc, and the load current iL. Use the Standard Resistor Values chart to find the nearest standard resistor value.
What should the base resistor be for a bipolar transistor?
For hard saturation, engineers usually choose a value of 10. Remember that a bipolar transistor is a current amplifier, because a small amount of current “Ib” through the base controls a larger amount of current “Ic” flowing through its collector.