EDN -- 03.28.96 Microprocessors

Microprocessors: March 28, 1996

16-bit microcontroller rides on 18-bit address bus. Part of the 16-bit modular microcontroller family, the 20-MHz 68HC16V1 integrates a CPU16 core (a 16-bit implementation of the 68HC11), queued serial module (QSM), general-purpose timer (GPT), and StreamLined Integration Module (SLIM) in a 100-pin TQFP. The SLIM provides a 16-bit data bus, 18-bit address bus, and 512 bytes of boot ROM for initialization code. In addition to the 68HC16V1, 20- and 25-MHz versions of the 68HC16Z1 microcontroller are also available. The Z1 devices pack a QSM, a GPT, 1 kbyte of standby RAM, a 10-bit ADC, and a System Integration Module into a 144-pin TQFP. The V1 chip costs $9.33, and the 20- and 25-MHz Z1 parts cost $13.20 and $13.80, respectively (10,000). Motorola Microcontroller Technologies Group, Austin, TX. (800) 441-2447.

Clock-tripled 486DX µP hits 120 MHz. Modeled on the 486 architecture, the ST486DX4V12HS µP reaches speeds of 120 MHz and operates from a 3.45V supply. The clock-tripled device features a write-back cache, a 486 floating-point unit, and a power-saving mode suitable for PCs running under Windows 95. The ST486DX4V12HS achieves a 21% average performance improvement over 100-MHz ST486 devices. Prices are about $0.60/megahertz (1000). SGS-Thomson Microelectronics, Lincoln, MA. (617) 259-0300.

DSP core packs on-chip peripherals. The Z8946X DSP core is a cost-effective alternative to embedded controllers in computer-peripheral and consumer-electronic equipment. The first to use the core, the Z89462, is a 16-bit, 40-MIPS device that offers a bit-field unit to manage microcontroller-system-control functions and such on-chip peripherals as 24-bit counter/timers, pulse-width modulators, bit I/O, synchronous serial ports, and a wait-state generator. On-chip memory consists of 1k word of program RAM and two 512-word blocks of data RAM. In a 100-pin PQFP, the Z89462 costs $11 (50,000). Zilog, Campbell, CA. (408) 370-8000.

Voice-controller ICs support caller ID, flash memory. Based on a Z8 microcontroller and a 16-bit DSP core, the Z89175 and Z89176 (ROMless) voice-controller chips integrate stored voice prompts; date/time stamps; and codec, caller-ID, and speaker-phone capabilities. Both of the devices work with a variety of low-cost flash memories and audio RAMs, including Samsung's KM29N040 512k×8-bit flash memory, and as many as two 4-Mbyte audio RAMs. The Z89175 has 8k words of DSP ROM. Housed in 100-pin QFPs, the parts cost about $6 in volume quantities. Zilog, Campbell, CA. (408) 370-8000.

ASIC core clocks to 120 MHz. Backed by a set of macrocells and macrofunctions for embedded systems, the ST486DX ASIC core offers full x86 functionality, as well as DOS and Windows compatibility. The CPU core builds circuits of >2-million equivalent usable gates. Because the device is based on the clock-tripled ST486DX4 µP, it operates as fast as three times the external bus speed to a maximum of 120 MHz. The ST486DX core comes with an 8-kbyte, on-chip cache. SGS-Thomson Microelectronics, Lincoln, MA. (617) 259-0300.

6805-class µC packs 4-kbyte ROM in 20-pin package. The CDP68H-C05J4 µC family, which provides a subset of the Motorola MC68HC05P4's functions, squeezes the CPU, support circuits, and 4 kbytes of on-chip ROM into a 20-lead package. The CDP68HC05J4 reduces the number of leads from 28 to 20 and doubles the amount of ROM previously available in a 20-lead package. Used for controlling general functions in cordless telephones and remote-control devices, the µC comes in versions that run at 4.2 and 8 MHz. Devices operate from 3 to 6V supplies, with data retained down to 2V. A low-power version operates from supplies as low as 2.4V. Prices start at $2 (10,000). Harris Semiconductor, Melbourne, FL. (800) 442-7747, ext 7428.