Low Frequency Transformer Impedance Matching
Low Frequency Transformer Impedance matching
Low-frequency transformers are used to propagate signal voltage and signal power
Low-frequency transformers can also achieve impedance matching between the circuit, the DC has a role in isolation, low-frequency transformer is divided into inter-stage coupling transformer, input transformer and output transformer, shape similar to the power transformer.
1. The inter-pole coupling transformer inter-stage coupling transformer is used between the two-stage audio amplifier circuit as a coupling element to transmit the output signal of the preamplifier circuit to the next stage and to perform appropriate impedance conversion.
2. Input Transformers In earlier semiconductor radios, the transformer used between the audio booster stage and the power amplifier stage was the input transformer, with signal coupling and transmission, also known as pushing the transformer.
The input transformer has a single-ended input and push-pull input. If the push circuit is a single-ended circuit, the input transformer is also a single-ended input transformer; if the push circuit is a push-pull circuit, the input transformer is also a push-pull input transformer.
3. Output transformer output transformer connected to the power amplifier output circuit and the speaker, mainly from the signal transmission and impedance matching role. Output transformer is also divided into single-ended output transformer and push-pull output transformer two.
Why is there a loss of transformer?
We can see the transformer inside the two roads: one is the circuit, one is the magnetic circuit. And people running the same physical consumption, in the magnetic circuit and the circuit "run" of course, there are losses it!
Magnetic circuit is composed of iron core, so the magnetic circuit loss is also called iron loss (no load loss); circuit is composed of copper wire, so the circuit loss is also called copper loss (load loss).
Then all the transformer losses are the same? the answer is negative. Different capacity and design of the transformer transformer loss is not the same. In the design of the same model, the greater the capacity loss is also greater. Transformer running, the output is different, then how to know it's the loss of it? Are the parameters of the transformer related to the loss?
1, the transformer capacity: Se
2, no-load loss: Po (iron loss)
3, short circuit loss: Pk (copper loss)
4, no-load current: Io