News and New Products

Microcontroller family extends performance of ultralow-power devices

By Robert Cravotta, Technical Editor -- EDN, 6/9/2008

Texas Instruments’ MSP430F5xx family of 16-bit microcontrollers improves peak processing performance over previous-generation MSP430 devices by more than 50% with a maximum operating frequency of 25 MHz. The processors support an active-power draw of 220 µA/MHz over the operating-frequency range. For designs requiring the lowest possible active-power draw, the devices’ power-management module supports a power draw as low as 160 µA/MHz with the core voltage at the lowest voltage setting, 1.35V, and operating as fast as 12 MHz. The devices support a 32-bit real-time clock with an alarm that operates with a standby current draw of 1.5 µA. The processor family can complete a wake up in less than 5 µsec with full status retention from both standby and sleep modes.

The new power-management module includes four frequency and voltage entries that enable designers to dynamically choose the optimum core voltage and guarantee perfect power-on-reset and supply-voltage supervision with monitoring.

Supporting designs based on two AAA batteries, the devices support read/erase/write capability to as low as 1.8V, enabling writes to flash down to battery end of life of 0.9V for each battery. The unified-clock system supports operation without a crystal to save costs. The DMA (direct-memory-access) controller can have as many as eight channels and supports data exchange with peripherals while the processor core remains in low-power modes, and digital and analog peripherals consume no power when they are not operating.

The new family provides as much as 1 Mbyte of linear-memory mapping, and it is 100%-set-compatible with earlier-generation MSP430 devices. The F54xx devices integrate as much as 16 kbytes of RAM and as much as 256 kbytes of flash, which doubles the maximum flash and RAM available on previous MSP430F2xx, F1xx and F4xx devices. The devices are available in 80- and 100-pin QFPs. The smaller, 128-kbyte-flash, 8-kbyte-RAM MSP430F5419 device is available for $3.61 (1000). The larger, 256-kbyte-flash, 16-kbyte-RAM MSP430F5438 is available for sampling now and sells for $4.85 (1000). More devices will be available for sampling in August at prices ranging from the $2.99 (10,000) MSP430F5418IPN and the $4.28 (1000), midsized, 192-kbyte-flash, 16-kbyte-RAM MSP430F5436. Future devices will include USB, encryption, RF, and LCD interfaces.