Freescale MCUs target smart-meter apps

freescalelogoAustin, Tex. — Freescale Semiconductor has introduced three advanced microcontroller (MCU) solutions, together with smart-meter reference designs, targeting electricity and flow meter applications. The microcontrollers enable smart meters to be designed with tamper detection mechanisms and real-time usage monitoring, providing customers with an extra layer of security for their smart-meter products.

Smart metering products enable two-way communication with the utility companies and the consumer to eliminate waste, optimize power and reduce energy consumption.

“Our goal is to provide developers with comprehensive plug-and-play solutions designed to alleviate cost and time-to-market concerns, while bringing everyone a step closer to a unified smart grid,” said Jeff Bock, director of product marketing for Industrial and Multi-Market microcontrollers at Freescale, in a statement. “Freescale’s smart energy technologies address smart metering and smart grid applications across the grid, enabling customers worldwide to provide secure, next-generation energy management solutions.”

The advanced Freescale devices have several key functions combined on one chip, which until now has been unavailable in a single solution, said Freescale. Thanks to the real-time clock (RTC) on Freescale’s metering solutions, utility companies may be able to implement different tariffs depending on time of the day, maximum demand and load availability.

In addition, the RTC has tamper detection mechanisms to detect fraud and send a trigger or error notice to the utility company when tampering is detected. It can also run separately with its own battery power supply in the event of a main power failure, which adds an additional layer of security in case tampering occurs during a power outage. Two separate blocks of flash memory allow a meter to continue operating on one flash bank while the other is being updated with new firmware, avoiding costly downtime.

The three devices include the MCF51EM256 for polyphase electricity meters, the MC9S08LH64 for low-cost single-phase electricity meters and energy monitoring, and the MC9S08GW64 for single-phase electricity, gas and water flow meters

The MCF51EM256 features a 32-bit ColdFire V1 MCU core with multiply accumulate unit, and includes a poly-phase software and hardware reference design for U.S. 110 volt and EMEA/ASIA 234 volt. It also includes four integrated 16-bit SAR ADC modules and a programmable delay block for phase error compensation to enable 3-phase energy measurement, an independent real-time clock with calendaring and tamper detection capability, and a flexible LCD controller that can run in ultra-low-power modes and support up to 288 segments. The device is pre-certified to popular standards including International Electrotechnical Commission (IEC).

The MC9S08LH64 features the 8-bit S08 core, a low-power integrated LCD driver, an embedded ultra-low-power oscillator that enables an accurate time base in low power modes, and an integrated 16-bit SAR ADC. A cost-optimized single-phase electricity meter reference design is available on request

The MC9S08GW64 features the 8-bit S08 core, an electricity metering analog front end with two independent 16-bit SAR ADCs, and a programmable delay block for phase error compensation as well as an integrated gas and water metering pulse counter that provides automatic sensor decoding and flow management while the product is in stop mode. Hardware and software reference designs are under development including a single-phase electricity meter with integrated AFE, as well as gas and water flow meter reference designs.

Freescale plans to announce a series of metering solutions later this year that meet different smart-grid applications.

Availability: The MCF51EM256 and MC9S08LH64 devices are available now. General availability of the MC9S08GW64 products will be announced later this year.

Pricing: The MCF51EM256 and MC9S08LH64 devices are priced at $3.97 and $2.79, respectively, both in quantities of 10,000.

Resources: Online training, videos, webcasts, technical documentation and application notes available at, and