Pecking order shapes up on flash

Electronic News, June 9, 1997 by Joyce Putscher

Until recently, the number of 8-bit microcontroller vendors offering block-erasable flash for standard production products, as opposed to prototyping or custom devices, has been limited. Atmel, Hitachi, Sanyo and Microchip Technology presented the only standard offerings. That field has widened to include Philips, NEC and Winbond. A little more than a week ago, Philips launched its first 80C51 flash MCUs and announced that, in addition, the company would be adding another flash family later this year. Integrated Silicon Solution, Inc. (ISSI) will be added to the players list in the third quarter of this year. Afterward, there will be two companies to bypass OTPs and to only offer mask-ROM and flash 8-bit MCUs: Sanyo and ISSI.

Thus, only seven players in the 8-bit microcontroller (MCU) merchant market offer standard flash memory versions, while almost all vendors offer families with one-time programmable (OTP) EPROM memory.

With regard to memory density, some 8-bit vendors concentrate in the low end, some in the midrange, while others are targeting the mid-to high-range. The high end tops out at 128K bytes--at least for currently available standard products. On June 9th, Atmel starts shipping its new 8-bit RISC AVR MCU family with flash and EEPROM, and plans to extend this line up to 128K bytes of flash by year's end.

For a number of microcontroller vendors, on-chip flash memory first became of interest for their 16-bit and then 32-bit MCU product lines. Here, players have concentrated on mid- to high-range flash densities. Many have come to market with 64K- to 128K-byte family members to support the greater memory requirements that some applications demand and to support more effective use of high-level languages.

Seven out of the top 10 players in the 16/32-bit MCU merchant market offer standard-product flash versions, with most offering OTP family members. In this market segment, Siemens, Motorola, SGS-Thomson Microelectronics, Hitachi, Mitsubishi, NEC, Sanyo and Toshiba currently offer standard flash microcontrollers, while another may emerge soon. In some instances, vendors offer flash MCUs not as standard products, but only as custom devices.

Some in the industry believe that microcontrollers with on-chip flash will displace those with embedded OTP memory in about three to four years. With breakthroughs in different EPROM architectures and technologies, the life of MCUs with on-chip OTP memories will be extended. This extended life cycle will be due to the resulting reduction in cost associated with these new architectures and technologies, and the fact that many low-cost, high-volume applications will not need reprogrammability.

A perfect example of one of these breakthroughs is the recent announcement by Samsung Semiconductor (San Jose, Calif.) with its new 8-bit microcontroller, the KS88P0916. This new OTP MCU incorporates the company's new EPROM technology that is contained in the same silicon area as the company's mask-ROM embedded memory. Considering the extra process layers involved, Samsung is offering this microcontroller for just a 10-20 percent premium over a mask-ROM version, and intends to even eliminate the premium entirely. This new embedded EPROM offers the same power consumption, voltage and speed as its mask-ROM counterpart.

Some vendors are currently offering flash MCUs for about the same price as their OTP versions, while others are asking for about a 20-40 percent premium over their OTP counterparts. These premiums are expected to decline gradually over the next several years. In conjunction with these reductions, new designs will proliferate that take advantage of the in-system programmability features, thus further driving the demand for embedded flash microcontrollers. Other OTP architectures will appear in the near future that will continue to drive down the cost of OTP MCUs, such that these devices will continue in popularity and displace some ROMless and mask-ROM MCUs. So, even as the market share of flash MCUs will increase at the expense of OTP MCUs, the market share of OTPs will likely rise at the expense of ROMless/mask-ROM MCUs.

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