Cypress has developed a power line reference design based on its PSoC programmable devices.
PSoCs include a microcontroller, programmable digital logic, and programmable analogue blocks.
The Cypress solution is to programme an FSK (frequency shift keying) PHY modem, network protocol and application code into the chip and, according to company marketing manager Ashish Garg, the only additional components required are two transistors for line driving and a high-voltage coupling capacitor.
"It cost $2-5 for the PSoC plus $2 for 220Vac interface components, or $0.30 for 12V or 24V interface components," he told EW.
Power networks have notoriously difficult impedance profiles, and can not cost-effectively be modified to give power line communication (PLC) devices an easy ride.
"The low-voltage version even works with one node connected directly across a vehicle battery," said Garg.
With a mains networks, "the solution offers greater than 97% packet success rates without retries and 100% success rates with retries built into the solution's coding," said Cypress.
"We have done tests in an average 3,500ft2 American house and it works in every power socket," added Garg.
The reference design is certified by CENELEC in Europe, and UL and the FCC in the US.
Cypress uses proprietary 2.4kbit/s FSK modulation between 130-134kHz, which is within the PLC communication band specified by European standards body CENELEC.
Other modulation schemes have been mooted for standardisation, including: SFSK (synchronous FSK) and OFDM (orthogonal frequency division multiplexing) system like PRIME.
"We can do FSK in a PSoC 1, SFSK in a PSoC 3, and PRIME in a PSoC 5," he claimed.
Transmitter power consumption is 630mW, and the receiver needs 500mW which Garg claims can drop to 25mW in sleep while retaining the ability to wake from a 135kHz signal.
Applications are foreseen with smart home control, including for colour-changing LED lighting, and for industrial applications like communication amongst solar panels in one-inverter-per-panel ('microinverter') environments.
Several high and low voltage development kits are available.
The CY3274 programmable high voltage power line communication development kit.
