Accent’s ASMgrid2 systems-on-a-chip (SoCs) fulfill the requirements of most new smart-meter designs today. These ICs provide complete single-chip and two-chip solutions including energy measurement, meter operation, home-area networking (HAN), and near-area networking (NAN) communications. Most of the U.S. and European communications standards are covered as well, providing flexibility to support current and future designs.
The ASM201 incorporates circuits for energy measurement with an accuracy of 0.1%. The chip also handles the LCD and includes power management monitoring and control. Its 2.4-GHz ZigBee PRO transceiver conforms to the 802.15.4 standard, which means that it’s SEP 2.0-ready (Smart Energy Protocol). Protocol stack processing is provided for the NAN link. Security is accelerated AES with memory protection and secured ports. The on-board processor is an ARM926EJ-S with flash and SRAM.
Designed to work with the ASM201, the ASM211 delivers the NAN communications link back to the utility (see the figure). It implements the Smart Utility Networks (SUN) IEEE 802.15.4g standard that operates at 915 MHz and supports the mandatory multiple versions of frequency shift keying (FSK) as well as the orthogonal frequency division multiplexing (OFDM) physical layer (PHY) that delivers a data rate to 800 kbits/s. The receiver sensitivity is –118 dBm. And, this IC includes an ARM Cortex-M0 processor with flash and SRAM.
The ASM221 single-chip solution has all the basic features of the ASM201 but uses an ARM Cortex-M3 processor. It doesn’t include the HAN transceiver but does provide a serial interface to support the selected HAN radio or power-line communications (PLC) modem. NAN communications functions support all the popular OFDM-based PLC standards including G1 and G3, PRIME, and IEEE 1901.2.
Samples of these devices will be available in the fourth quarter of 2011.