In the simplified drawing method of the AC path in the triode amplifier circuit, it is said that the DC power supply is regarded as a short circuit. Are both the DC voltage source and the current source short circuited?

一沙一世

In the simplified drawing method of the AC path in the triode amplifier circuit, it is said that the DC power supply is regarded as a short circuit. Are both the DC voltage source and the current source short circuited? [Copy link]

邀请：@maychang   @vincentc543   @hahajing   @吾妻思萌   参与回复

In the transistor amplifier circuit, the simplified drawing of the AC path says that the DC power supply is considered to be a short circuit. Are both the DC voltage source and the DC current source short-circuited?

呜呼哀哉

It should be that the DC voltage source is short-circuited and the DC current source is open-circuited. What we need to do here is to assume that there is no input and the current source short-circuited is invalid.

maychang

[Are both the DC voltage source and the DC current source short-circuited? ]

Voltage sources are considered short circuits and current sources are considered open circuits.

maychang

[In the triode amplifier circuit, the simplified drawing of the AC path says that the DC power supply is considered to be short-circuited. Are both the DC voltage source and the DC current source short-circuited? ]

In the basic triode amplifier circuit, no DC current source is used, only a DC voltage source, which is referred to as a "DC power supply" in the quotation.

chunyang

When an AC signal is added to an ideal voltage source, the output voltage of the voltage source will not change as the voltage of the external AC signal changes. Therefore, for the external AC signal, the ideal voltage source is equivalent to a short circuit.

When an AC signal is added to an ideal current source, since the output current of the current source remains unchanged, the current obtained by the load is the direct arithmetic superposition of the external AC signal and the current source output. Therefore, for AC signals, the ideal current source is equivalent to an open circuit.

led2015

Generally, only DC power supplies are considered as short circuits, while DC voltage sources and DC current sources need to consider their internal resistance and cannot be simply considered as short circuits.

一沙一世

led2015 Published on 2023-3-29 23:40 Generally, only the DC power supply is regarded as a short circuit, while the DC voltage source and DC current source need to consider their internal resistance and cannot be simply regarded as a short circuit.

Thank you. When you say that [DC power supply is generally considered as a short circuit], is this [DC power supply] a voltage source or a current source?

maychang

Yishayishi published on 2023-3-30 08:49 Thank you. When you say [generally only DC power supply is regarded as short circuit], is this [DC power supply] a voltage source or a current source?

[Is this [DC power supply] a voltage source or a current source? ]

This [DC power supply] is the DC power supply that powers the triode amplifier circuit. It is similar to a voltage source.