Voice Recorder From Texas Instruments

APPLICATION NOTES The contents of this column are based on information obtained from manufacturers in the electronics industry, or their representatives, and do not imply practical experience by Elektor Electronics or its consultants Voice recorder from Texas Instruments For many years now, the most popular means of analogue recording and playing back of audio signals has been the cas- sette recorder. But even here, digital techniques are beginning to make inroads. True, available material allows only relatively short recording times, but for a number of applications, for instance, telephone answering machines, advertising messages, memory aids, alarm installa- tions, and so on, it is perfectly usable. A new lc from Texas Instru- ments, the TMS 3477, is intended as basis for such equipment. Apart from RAM, all necessary functions are available on the chip. The block diagram of a possible system is shown in Fig. 1. The lc may be operated in two different ways. The simpler is by mea...