Every now and then, you still see one of the old tape-based answering machines sitting on someone's desk. It performs the simple job of recording messages with reasonable reliability, and it is good enough for some users.
But answering machines have come a long way since the days of tape cassettes. Today's digital machines provide a complete voice mail system in the home. You can save messages or skip them. You can fast-forward through the lot or specify the particular message you choose to review. And you can depend on the machine to perform without malfunction for as long as you own it.
The driving force behind these advances in answering machines -- along with huge leaps in other applications, such as cellular telephones, hard disk drives, direct satellite television and more -- is the increasing availability and versatility of inexpensive digital signal processors (DSPs). With performance increasing by an order of magnitude every three to five years while cost drops at the same rate, DSPs help designers add remarkable new features at prices users gladly pay.
In the new digital answering machines, DSPs perform the compression/decompression that makes voice mail-like features possible. In digital cellular telephones, these processing engines enable hands-free operation as well as voice mail features. In hard disk drives, they manage seek and track tasks so effectively that disk capacities can reach one gigabyte and more.
Many of these capabilities, of course, are not new. Texas Instruments pioneered DSPs more than 12 years ago, and their importance in the marketplace has been growing exponentially ever since. Only recently, though, has the price of these devices dropped to the point at which they are practical for high-volume applications.
When TI introduced its first DSP, performance was about 5 million instructions per second (MIPS). The cost was in the $1,000-per-device range. That meant that the price per MIPS was about $200. DSPs were used only in research or by the military for sophisticated weaponry, because few other potential users could pay the bill.
Today, TI DSPs offering the same performance cost less than $5 per device, or less than $1 per MIPS. The same price per MIPS ratio is available in DSPs delivering 40 to 50 MIPS performance.
For equipment manufacturers, this dramatic drop in price has been an important enabler for new applications. It has allowed consumer products companies to market full-featured digital answering machines that cost no more than the old tape-based machines. It has pushed the trend away from analog cellular phones to digital sets that sound better and perform many more functions.
Inexpensive DSPs provide the computing power needed to compress and decompress signals in RCA's new direct satellite TV systems. And they do it at a price that makes these multi-channel, high resolution receivers attractive to consumers.
High-density, small-form factor hard disk drives could, conceivably, be designed with general purpose processors to perform basic servo-control functions. But few drive makers would choose a $150 integrated circuit device when a $15 DSP can do the job more efficiently.
Inexpensive TI DSPs will clear the way to more applications in the near future. They will replace microcontrollers to regulate motor speed and power consumption in home appliances. And they will facilitate new features, such as a dishwasher that senses when dishes are clean and turns itself off.
Declining DSP price, coupled with increased performance, not only will make video conferencing and document imaging practical for the office, it will make these features affordable for the home. Dick Tracy's wrist watch may still be a way off, but the video telephone we have heard about for years finally is just around the corner.
The dramatic improvements in the price/performance ratio of TI's DSPs results from the company's manufacturing capacity and advanced process technology. TI has led in both of these areas since DSPs were introduced, and we intend to extend our leadership in the years to come.
As manufacturers develop new products and consumers demand new features, TI will continue to refine DSP technology to provide high-performance at continually lower prices. In DSPs, TI is committed to enabling low-cost solutions and high-performance solutions through silicon integration.
March 1995, vol. 12, no.2
TI Home
Search
Semiconductor Home
