Telephone line interfacing circuits these days seemed to be a 'lost art'.
A search on Digi-Key, Octopart, with the keyword SLIC and sorting by ICs with existing stocks gives the highest counts for chips that are obsolete !
And the newer chips, which integrates the 'SLIC' (subscriber line interface circuit) with ADC, DAC has the digital interfacing protocols omitted in the data sheet. Merely gives the electrical specs with nothing about the SPI and such interface protocols. I'd guess they'd only cater to bulk orders.
Hence, I ended up searching for discrete circuits, some good ones are like
https://www.epanorama.net/links/telephone.html
https://www.epanorama.net/circuits/teleinterface.html
http://www.next.gr/telephone/Telephone-Circuits/
While there are many circuits posted, for some of them, one may wonder if it'd work. And for 'others' a lot of them uses a transformer. I'd guess it is for isolation.
Are there any good circuits or rather ICs that can do without a transformer, as like most 'transceiver' or 'line driver' chips?
can't seem to find many of them except like HC5503, even the datasheet looks 'old'
https://www.digikey.com/en/products/detail/rochester-electronics-llc/HC5503CCB/12134034
A search on Digi-Key, Octopart, with the keyword SLIC and sorting by ICs with existing stocks gives the highest counts for chips that are obsolete !
And the newer chips, which integrates the 'SLIC' (subscriber line interface circuit) with ADC, DAC has the digital interfacing protocols omitted in the data sheet. Merely gives the electrical specs with nothing about the SPI and such interface protocols. I'd guess they'd only cater to bulk orders.
Hence, I ended up searching for discrete circuits, some good ones are like
https://www.epanorama.net/links/telephone.html
https://www.epanorama.net/circuits/teleinterface.html
http://www.next.gr/telephone/Telephone-Circuits/
While there are many circuits posted, for some of them, one may wonder if it'd work. And for 'others' a lot of them uses a transformer. I'd guess it is for isolation.
Are there any good circuits or rather ICs that can do without a transformer, as like most 'transceiver' or 'line driver' chips?
can't seem to find many of them except like HC5503, even the datasheet looks 'old'
https://www.digikey.com/en/products/detail/rochester-electronics-llc/HC5503CCB/12134034
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