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Chip Amps Amplifiers based on integrated circuits

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Old 20th May 2006, 06:23 AM   #1
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Post lm1875

my lm1875
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Old 20th May 2006, 08:24 AM   #2
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Default high output impedance

I see the loudspeaker current-sense resistor signal gets sent into the feedback network and inverting input. You amplifier will have an output impedance higher than normal. This is not always a good thing because the speaker output will rise a lot at it's resonant frequency.
Best-ever T/S parameter spreadsheet.
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Old 23rd May 2006, 12:11 AM   #3
preiter is offline preiter  United States
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In a vain attempt to educate myself, I wonder if you wouldn't mind answering a couple of questions about the design.

I don't understand the resistor network on the output of the device. You have a resistor between the speaker output and ground, another in parallel with the speaker and the 10k resistor. What are those for?

Also the two caps on the input, what do those do?

I understand the basics of chipamp circuits, but when they start to get fancy I'm totally lost.
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Old 23rd May 2006, 02:23 AM   #4
Leolabs is offline Leolabs  Malaysia
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"dian liu hui shu",not bad.How does it sound???
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Old 23rd May 2006, 03:28 AM   #5
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the pcb on this sch
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