Admitted, the title sounds weird. Actually, we already have a thread concerned with the use of LM1875, in particular with more in parallel, as power stage in a composite amplifier. The final aim there is to test such a composite amplifier in BTL-configuration. Without being aware when I bought my LM1875, I ended up with specimens that are probably “fake” and do not behave fully as LM1875 ICs delivered straight from TI. My “fake” LM1875 sometimes perform more like TDA2050. As the TDA2050 is pin-compatible with the LM1875 and their specifications are pretty much alike, this existing thread also include the use of TDA2050. ST no longer produces TDA2050 but a company in Taiwan, Unisonic, produces a version called UTC-TDA2050V that seems to perform very well and can be bought at a very good price. Such is for the existing thread.
Work with LM1875 and TDA2050 in the existing thread got to a point where it was difficult to disregard that other chip-amps may also be very suited for composite amplifiers. In particular for higher power levels. In posting #510 ( LM1875 in parallel configuration and used in a composite amplifier. ) of the existing thread, a scheme was drafted mentioning a plurality of chip-amp candidates.
Before a chip-amp is used in a composite amplifiers, its behavior should be investigated such that an implementation of the chip-amp is used in the composite amplifier that is 100% predictable and reliable. This sounds trivial but even the well known LM1875 showed some characteristics, like self-oscillation and de-rated operational limits, that took most of the time before the complete amplifier performed well. Another problem related to use of chip-amps at a gain below the minimum gain specified in the datasheet.
For other chip-amps than LM1875/TDA2050, where should the results from investigations be disclosed? The existing thread is already becoming comprehensive with LM1875/TDA2050 issues, parallel-coupling issues, controlling OP-AMP issues etc. Therefore, the present thread is started with the purpose to disclose experimental results and considerations relating to these further chip-amps, when using them below the minimum gain, when connecting them in parallel, when improving stability, when protecting them from overload etc.
FF
Work with LM1875 and TDA2050 in the existing thread got to a point where it was difficult to disregard that other chip-amps may also be very suited for composite amplifiers. In particular for higher power levels. In posting #510 ( LM1875 in parallel configuration and used in a composite amplifier. ) of the existing thread, a scheme was drafted mentioning a plurality of chip-amp candidates.
Before a chip-amp is used in a composite amplifiers, its behavior should be investigated such that an implementation of the chip-amp is used in the composite amplifier that is 100% predictable and reliable. This sounds trivial but even the well known LM1875 showed some characteristics, like self-oscillation and de-rated operational limits, that took most of the time before the complete amplifier performed well. Another problem related to use of chip-amps at a gain below the minimum gain specified in the datasheet.
For other chip-amps than LM1875/TDA2050, where should the results from investigations be disclosed? The existing thread is already becoming comprehensive with LM1875/TDA2050 issues, parallel-coupling issues, controlling OP-AMP issues etc. Therefore, the present thread is started with the purpose to disclose experimental results and considerations relating to these further chip-amps, when using them below the minimum gain, when connecting them in parallel, when improving stability, when protecting them from overload etc.
FF
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