NUREMBERG, Germany -- Falling costs for 32-bit microcontrollers (MCUs) has prompted considerable speculation about them displacing 8-bit MCUs for new designs. But 8-bit MCUs aren't nearly dead yet. Silicon Labs just announced at Embedded World a new series of 8-bit MCUs that target a range of cost-, power-, and space-sensitive applications in the Internet of Things (IoT).
Silicon Labs is investing in new 8-bit devices, the company's director of marketing for 8-bit MCUs Tom Pannell told EE Times, because developers are looking for simplicity to speed their design efforts. "We've been working to provide performance, value, and ease-of-use for IoT developers," said Pannell. "The 8-bit architecture is easier to use than others, and offers lower cost and power. Our high-speed, pipelined 8051 core provides the performance."
The company also sees the 8-bit market as still thriving. The company quoted a report from Tom Hackenberg of market research firm IHS indicating that 8-bit devices will retain a third of the MCU market for several more years. Indeed, IHS expects the market to growing in value, reaching $7.8 billion in 2018.
To address a diverse range of applications, Silicon Labs has released the new EFM8 MCU family as three product lines, all with an apiary theme: Busy Bee, Sleepy Bee, and Universal Bee. A set of six low-cost (<$30) starter kits for these devices were also announced.
The Busy Bee series provides a balance of low power and high performance for cost sensitive applications. It offers clock speeds up to 50 MHz and as much as 16k of flash. Highlights of its peripheral mix include a 12-bit ADC; dual comparators with built-in analog reference; UART, SPI, and I2C interfaces, and PWMs for motor control.
The Sleepy Bee targets ultra-low power applications. Its active current is 150 µA/MHz and sleep mode is only 50 nA. The devices feature a 12-channel touch controller that remains functional during standby mode, allowing the MCU to "wake on touch."
The Universal Bee series target USB based applications, offering a USB interface that includes a charger detect circuit to reduce the need for external components. The devices also include a built-in oscillator and clock recovery circuit.
As part of the simplification theme Silicon Labs had in mind when designing the EMF8 family, the IO peripherals on all the devices have the support of a full digital crossbar switch. This switch, according to Pannell, eliminates compromises when working with a small pin-count device. "These interfaces are not multiplexed the way some MCUs are," said Pannell, "so you don't eliminate the availability of one peripheral when you choose to use another. As long as there is a pin still available, you can route any peripheral out."
The company has also expanded its Simplicity Studio development platform to help ease designer tasks. The platform now supports all of Silicon Labs' devices from its 8- to its 32-bit architectures. This allows a designer to work with an 8-bit device at first, and upgrade to a larger device when needed without having to learn a new design tool.