What are the input and output impedances for an ideal voltage amplifier and an ideal current amplifier?
An ideal amplifier has infinite input impedance, zero output impedance, and a fixed gain at all frequencies. An ideal op amp has infinite input impedance and zero output impedance, but has infinite gain.
What is input impedance of an amplifier?
BJT Amplifier Input/Output Impedance Input impedance is defined as the ratio of imput voltage to input current. It is calculated from the AC equivalent circuit as the equivalent resistance looking into the input with all current cources replaced by an open and all voltage sources replaced by a short.
What are input and output impedances?
The output impedance refers to the impedance, or opposition to current flow, of the component that often bears an electrical source to “drive” a load component. Meanwhile, the input impedance refers to the load component’s opposition to current flowing in from the electrical source.
What is input and output impedance of an amplifier?
The input and output impedance of an amplifier is the ratio of voltage to current flowing in or out of these terminals. The input impedance may depend upon the source supply feeding the amplifier while the output impedance may also vary according to the load impedance, RL across the output terminals.
What is the input and output impedance of an amplifier?
In reality one of the terminals is common between the input and output representing ground or zero volts. When looking from the outside in, these terminals have an input impedance, ZIN and an output impedance, ZOUT. The input and output impedance of an amplifier is the ratio of voltage to current flowing in or out of these terminals.
When do impedance conflicts occur in an amplifier?
“ Impedance conflicts ” happens between an output and an input terminal. Basically, we can distinguish three scenarios of connection. The first one, is when a source is connected to an amplifier, this is what is shown in Figure 2. The second case is when the amplifier is connected to a transducer.
Can a high input and low output impedance match?
Nowadays, as a general rule, high input and low output impedances are the norm, even if it does not lead to an impedance match. However, we will see in the next section that in some cases, impedance matching can be more suitable.
What kind of impedance does a FET have?
FETs have high input impedance and can act as voltage amplifiers, I think this confirms that voltage amplifiers have high input impedance. On the other [hand] when we come to Common Collector and Common Base Amplifiers, the former one high input impedance but have voltage gain of less than 1.