Why would we like the output impedance of a current mirror to be high?

An important feature of the current mirror is a relatively high output resistance which helps to keep the output current constant regardless of load conditions.

Why is there high output impedance?

The high impedance ensures that it draws very little current. It is the amplifier’s task to convert a low energy, voltage-driven signal into a higher-voltage output signal.

Which of the following current mirror circuit has high output resistance?

Explanation: The output resistance of Wilson current mirror is substantially greater than ≅(β× Output resistance)/2 than Simple or Widlar current source.

Which current source gives high output resistance?

Why should the output impedance of a current source be much greater than the input impedance of the load? – Electrical Engineering Stack Exchange.

What is the purpose of using current mirror?

The current mirror is used to provide bias currents and active loads to circuits. It can also be used to model a more realistic current source (since ideal current sources don’t exist).

What is the purpose of current mirror circuit?

A current mirror is a circuit designed to copy a current through one active device by controlling the current in another active device of a circuit, keeping the output current constant regardless of loading.

Why do current sources have infinite impedance?

Current always takes the path of least resistance. Thus, in order for current to go to the path of least resistance, we must set up the source and load so that the source has much higher resistance than the load. This is why we construct the ideal current source to have infinite internal resistance.

What is current mirror circuit?

A current mirror is a circuit designed to copy a current through one active device by controlling the current in another active device of a circuit, keeping the output current constant regardless of loading. The current mirror is used to provide bias currents and active loads to circuits.

What is the output impedance of a current mirror?

Current mirrors take a positive current (source) and generate a negative current (sink). Current mirrors have low input impedance, so the ‘reference’ current can be from a poor current source (output impedance 1k ohms) and give rise to a mirrored current that is a better current source (output impedance 100k ohms).

What is the use of current mirror in current sensor?

Current mirrors with sense-resistor inputs are used as current monitors high side current sensor as well, with highly attenuated output current. The low input impedance, like an ammeter, is a major benefit. Current mirrors have a wide range of uses. There are many answers to your questions.

What is the basic structure of current mirror?

We can generalize this basic current mirror structure with this first observation: A current mirror consists of a low impedance input stage connected to a high impedance output current stage. Conceptually, an ideal current mirror is simply an ideal current amplifier with a gain of -1.

What are the limitations of a mirror circuit?

The third limitation is the minimum voltage drop across the output leg of the mirror necessary to maintain the desired output current. This minimum voltage, called output compliance, is determined by the need to keep the output transistor of the mirror in the active region.