MCUs offer enhanced memory, system features

STMicroelectronics announced that it has completed its ST7 UltraLite family of tiny 8-pin MCUs—intended for simple and very cost-sensitive applications with the introduction of the ST7FLITEU0 series. The new device series is said to add more memory and valuable system features to the rich peripheral set of the existing devices. Its availability in 8-pin SO, DIP and 0.9mm-thick DFN packages, with temperature qualification up to 125°C, makes the new series suitable for HVAC, home appliance, lighting control and power-tool markets.

With a 2Kbyte flash program memory, twice as large as previous devices and 128bytes of data EEPROM, the new tiny devices have a significantly larger software capacity. They also include a trimmable 8MHz RC oscillator, with prescaler ratios down to 500kHz, and a very stable and accurate low-voltage and auxiliary voltage detector.

The small 8-pin MCUs target simple motor drives and include features such as an embedded 12bit auto-reload timer, operating over a 2kHz to 4MHz range, which can generate four independent PWM signals, with output compare function. The timer also includes programmable dead time generation for the half-bridge driving mode in which PWM signals must not be allowed to overlap, plus programmable duty cycles, polarity control and programmable output modes.

Other key system peripherals are an 8bit Lite timer with prescaler, watchdog, real-time base and input capture as well as a very fast, five-channel, 10bit ADC with 3.5?s overall conversion time, which is claimed to be the fastest in the 8bit MCU market. Five power-saving modes—Halt, Auto Wake-Up from Halt, Active Halt, Wait and Slow—offer the designer very high flexibility to minimize the overall power consumption in power-critical apps.

Development support is available through a complete set of hardware and software tool chains from ST and from third parties. The tools—such as ST's Stick Programmer and the Raisonance ReVA Evaluation kit and R-link USB Debugging and Programming Tool—will enable developers to rapidly and efficiently create, build and debug low-cost MCU-based systems. These tools, which also provide an excellent introduction for new users to the ST7 development environment, integrate easily with the free ST7 C compiler from Cosmic (up to 16K code-size, free of charge) and are supported by ST's free STVD7 Software IDE.

Samples of the 8-pin ST7FLITEU0 are available now in SO8, DIP8, DFN8 and DIP16 (for sampling only) packages, with the development tools. Volume production will begin in Q2 '07. Pricing for 10,000-unit quantities starts at $0.55.