GreenChip is a technology brand of Philips Semiconductors (now NXP Semiconductors) and is used in the company’s range of power adapter ICs with the same name. GreenChip ICs are used in power adapters and power supplies, as well as CFL bulbs and LED lighting products.

A recent NXP innovation is their GreenChip TEA1708 – an automatic discharge IC for X capacitors. The chip is used in power supplies.

Power supplies have traditionally relied on resistive discharge for X capacitors, which are used to reduce EMI (electromagnetic interference). By automatically discharging the X capacitor when the power supply is disconnected from the mains, the TEA1708 reduces power consumption by 20 – 30 mW, compared to using resistive discharge.

In addition to the automatic discharge functionality, the TEA1708 integrates a 500V clamping circuit, protecting the IC during mains surges and making the device more rugged. No additional metal-oxide varistor (MOV) is required to protect the TEA1708.

In a typical application with only two 200 kΩ resistors, the maximum differential mode mains surge voltage allowed exceeds 6 kV. The breakthrough reduction in power consumption achieved by the TEA1708 – combined with its ruggedness in withstanding power surges – make it a compelling solution for power supply manufacturers aiming to comply with new regulatory requirements such as Version 5 of the Code of Conduct for External Power Supplies and the amended ErP Lot 6, both introduced by the European Commission earlier this year.

“Power supply manufacturers face the ongoing challenge of stricter regulations on energy consumption at low load and no-load standby power. Every milliwatt of power savings counts, and this chip has only 1 mW of power consumption, which provides an important alternative to using resistors in discharging X capacitors,” said Marcel van Roosmalen, general manager, product line power solutions, NXP Semiconductors.

Saving a few milliamps in a 20KW transmitter probably won’t make much difference in overall product efficiency. However, save 30mW in every power supply mounted in a few dozen racks does add up, add to that GreenChip-type LED lighting.

With the increasing emphasis on ‘green’, everyone, including chip makers will search for ways to get as much power and performance out of products, with as little power required in as possible.