Semiconductor History

In 1962 Mullard (Philips) and GEC pooled their resources and facilities to create Associated Semiconductor Manufacturers. Mullard owned 2/3 of the combined business. GEC pulled out in 1969. This is a small signal diode CV7364/AAZ12, germanium, Vf=258mV.

Back in the day I knew about DSD (Direct Stream Digital) and SACD (Super Audio CD) but it passed me by. I was still in Burr-Brown when DSD data converter ICs were first being developed by the design team in Japan, and I'm sure I was present when they were being presented at seminars to customers, but at the time I had little or no interest in diving in personally. Burr-Brown invested heavily in designing ICs for the upcoming market demand, but as history tells us, it didn't become mainstream. Certainly not in the US, less so in Europe, but in Japan there was always demand. Philips and Sony originally developed SACD as the high end next generation of CD, and certainly the format was capable of encoding a significantly higher level of audio information on the platform. DSD was a delta-sigma bitstream format that sampled 1-bit at 2.8MHz. Philips Semiconductors (amongst others) developed an SACD processor and Burr-Brown (amongst others) developed DSD Digital to Analog converters. L...

Inside the Philips FC920 cassette deck from 1993. Recent purchase for a very small amount of money, to explore analog cassette tapes with better sounding equipment. This machine was equipped with Dolby HX-Pro which improved the overall sound of pre-recorded cassette tapes. It wasn't a noise reduction system like Dolby B or C, but was a dynamic signal bias system, implemented during the tape transfer process. Standard biasing mixed a high frequency fixed signal  to the source, to make the signal more linear (and better sounding).    HX-Pro (invented by Bang and Olufsen), made the bias dynamic, by reacting to the high frequency components of the music,  inside a feedback loop. The NEC chip implemented the HX-Pro function in the cassette deck. The cassette decks also had to be biased for different tape types, Ferric, Chrome or Metal, during production. You can see the adjustment components next to their text.

CD-i Player Audio Section The Philips CD-i was the first CD based movie and game unit. Before PC CD-ROMs and the PlayStation. It was so ahead of the curve at the time. Philips was a major consumer electronics innovator. Present in the player's audio section, the Crystal CS4328 was a well regarded Digital to Analog converter in the early 90s. A number of high end CD players used it, for example the Quad CD-67 from 1993. The CD-67 retailed at 795GBP and used a Philips CD transport mechanism. The CS4328 is a high performance 18 bit DAC and the AD7528s shown are dual 8 bit DACs. The K version of the CS4328 shown here is the -93dB typical (-90dB max) higher THD+N spec version. SNR is 120dB min. Power supply filtering is good on the device with tantalum and surface mount ceramic capacitors in parallel on the +/-5V analog supplies and +5V digital supply. If you look at the service manual schematics there are different player options. One uses the Philips SAA7321 Bitstream DAC and...