ABSTRACT
This is an example of: Using a resistor to convert a current into a
voltage. Example
A transistor (Note: not saturated) has a collector current of 3.5 mA. The supply voltage is 9 V and the collector resistor (R3) is 1 kΩ. What is VOUT" The voltage across the resistor is: v i x R3 = 0.0035 x 1000 = 3.5 V One end of the resistor is connected to the positive supply line, so it is at 9 V. If there is a voltage drop of 3.5 V, the other end is at 9 - 3.5
= 5.5 V. As the current increases, the voltage drop increases and VOUT falls As the current decreases, the voltage drop decreases and VOUT rises. Summing up:
The voltage signal is proportional to the inverse of the current signal.
