Maxim reference platform accelerates design of next-generation smart meters

SUNNYVALE, USA: Maxim Integrated Products introduced the Newport smart meter reference platform. Integrating the latest in metrology, security, and powerline communications (G3-PLC) technology, this reference platform gives utilities a versatile way to evaluate smart grid technology, and gives manufacturers an easy-to-use smart-meter design to accelerate time to market.

High integration and best-in-class accuracy reduce infrastructure costs and Newport’s highly dependable, flexible, and robust components allow performance in adverse conditions. This design demonstrates Maxim’s commitment to providing solutions for metrology, communication, security, interface, power, and timekeeping to the smart grid. A separate G3-PLC concentrator board is available to support meter-to-concentrator communications testing.

Supporting known system requirements; Anticipating unknowns
The rapid rollout of the smart grid is characterized by certainties and uncertainties. All smart meters need high accuracy, robust communication, security, and a long field life. To ensure that a design meets these performance criteria, the Newport evaluation platform integrates the 71M6541 energy-metering system on chip (SoC) that provides 0.1% accuracy across a wide current range of 2000:1.

The G3-PLC chipset, which includes the MAX2991 and MAX2992, features adaptive tone mapping, notching, and robust mode to ensure communication in the noisiest of conditions. The MAXQ1050 secure microcontroller supports advanced and scalable encryption standards and protects against physical attacks from hackers. Maxim’s long-standing quality ensures that these components will operate well in all field conditions for a long time.

The demands of new applications, such as EV reverse flow control, also mean that there are evolving requirements in smart grid implementation. The powerful components in the Newport smart meter reference platform provide the flexibility to handle uncertainties such as security algorithms, different communication protocols, and the need for field-upgradable meters. By using this smart-meter platform, designers can evaluate the MAX2991/MAX2992 G3-PLC compliant chipset, the 71M6541 metering SoC, and the MAXQ1050 secure microcontroller for their next-generation smart meters.

High integration ensures versatility
The Newport platform includes two communications sockets, allowing for independent neighborhood area network (NAN) and home are network (HAN) interfaces. Maxim’s G3-PLC chipset (MAX2991/MAX2992) is installed in one socket to provide communication for either meter to concentrator (route A), meter to in-home display and home gateway (route B), or both.

The chipset complies with the emerging IEEE(R) P1901.2 standard for OFDM-based communication over power lines and offers guaranteed interoperability. The MAX2992 also includes an on-chip CCM authentication coprocessor with AES-128 encryption/decryption.

The 71M6541 highly integrated metering SoC provides the metrology for the Newport platform. This field-proven solution features < 0.1% accuracy over the -40 degrees Celsius to +85 degrees Celsius industrial temperature range and 2000:1 current range. The 71M6541 combines a powerful, programmable, and customizable 32-bit metrology computation engine, a 22-bit delta-sigma ADC featuring the company’s Single Converter Technology(R); a 5MHz 8051-compatible MPU core with a low-power RTC and digital temperature compensation; flash memory; LCD driver; UARTs; and I2C interface.

This combination of blocks allows the system to be optimized for specialized measurements and to work with various sensors including shunts, current transformers, and Rogowski coils. The Newport platform is also the only solution today that supports isolated shunt-metering technology that reduces BOM cost, while enhancing reliability and immunity to magnetic tampering.

A major concern about smart grid security is the ability to access the grid through the meter. If perpetrated by a cyber criminal, potentially disastrous actions could cause widespread harm to the grid. To combat this, the Newport platform adds the MAXQ1050, which supports advanced asymmetric encryption schemes such as elliptic curve and also protects against physical hacking.

The MAXQ1050 incorporates a sophisticated security mechanism to protect secret key data; two self-destruct inputs and various other environmental monitors (temperature and voltage sensors) erase secret key data when an attack condition is detected, thereby preventing sensitive information from falling into the hands of an attacker. The device supports high-speed encryption with hardware accelerators for AES, RSA, DSA, ECDSA, SHA-1, SHA-224, SHA-256, and 3DES. A true hardware random-number generator is included for key generation and challenge generation.

The Newport smart grid platform includes several other important components to ensure a successful design evaluation. Complete power management is provided by the MAX17498, a current-mode pulse-width-modulated regulator for AC-DC and DC-DC power-conversion applications. The DS3231M real time clock offers enhanced timing accuracy, and the MAX13256 and MAX13412 provide an isolated RS-485 interface.