Summit Expands Microprocessor Supervisor Family.

CAMPBELL, Calif.--(BUSINESS WIRE)--Sept. 8, 1998--Summit Microelectronics has enlarged its offering of precision microprocessor supervisory circuits with a device that includes VCC monitor/reset function, a power fail monitor with independent interrupt output and 16K-bits of nonvolatile memory.

These parts, the S4261 S42WD61, will allow designers to reduce their system component count and system cost.

These devices -- unique in the semiconductor industry because of the on-board EEPROM -- monitor the microprocessor supply voltage within a system and will generate active-hi and active-low reset outputs if that voltage falls below a certain preset level.

In addition, these circuits contain a separate analog input that allows a second voltage to be monitored, and if this input voltage falls below the comparator's threshold, a non-maskable interrupt will be generated.

"The second voltage could be the system's unregulated supply, in which case the devices can provide early warning of a power failure," explained Rich Palm, Summit's Vice President of Marketing. "It could also be a second voltage on a dual voltage PCB or it could be used as a low battery voltage warning."

The S42WD61 incorporates a watchdog timer to prevent system downtime. This watchdog automatically resets the system if the timer is not cleared within 1.6 seconds.

This family of devices, which includes the S4242 and S42WD42, is the world's first full-featured microprocessor supervisors that include on-board nonvolatile memory, enabling designers to eliminate one or more circuits in a typical microprocessor-based system.

The device's 16K of EEPROM communicates via a standard 2-wire serial interface (I2C). Incorporating a reset circuit with the EEPROM provides WRITE protection of the memory during low supply-voltage conditions.

"The importance of this feature is frequently overlooked and it may result in data corruption problems. Hence, the S42WD61 offers a more compact and reliable system solution at or below the price of a traditional microprocessor supervisory circuit," explained Palm.

The nonvolatile memory is guaranteed to perform 1,000,000 erase/write cycles and data retention is specified as 100 years, with or without power applied.

The S4261 and S42WD61 are available for 3- and 5-volt systems and operate with a 50micronA max supply current at 5V. The devices are available for operation over the industrial temperature range of -40 to +85 degrees Centigrade. The circuit is available in 8-pin surface- mount SO-8 and 8-pin PDIP packages with prices starting at $1.87 in 1,000-unit quantities.

Summit Microelectronics, Inc. focuses on the integration of analog and EEPROM technologies to provide cost-effective solutions to a variety of applications in the telecommunications, consumer and automotive markets.

The Company's website is www.summitmicro.com.

    CONTACT: Summit Microelectronics, Campbell
              Rick Orlando, 408/378-6461
              Rich Palm, 408/378-6461