Semtech has launched a 20MHz buck converter that can use inductors formed from PCB tracks.
This follows on from an announcement that Peregrine Semiconductor plans to use silicon-on-sapphire to reach a similar switching rate.
Semtech revealed its 20MHz switcher, dubbed SC220 and already in production, at the IEEE Applied Power Electronics Conference and Exposition in Florida.
"The SC220 is the industry's first buck regulator that enables designers to draw their own ¬¬¬¬inductors directly on the PCB," said Semtech. "This device offers a 20MHz switching frequency that, when used with our inductor technology, for the first time allows PCB trace inductors to meet or exceed the EMI performance of chip inductors."
At this frequency, output capacitors as small as 1µF can be used in some applications.
EMI is reduced by making the single inductor needed in the circuit out of two small series-connected inductors placed next to each and connected in magnetic anti-phase to partially cancel one another's magnetic fields.
Semtech has apparently managed to patent this technique.
"In automotive power management, the technology enables a non-shielded inductor to be used for the first time," claimed Semtech marketing director Athar Zaidi.
The SC220 steps down 2.7 to 5.5V inputs and delivers outputs down to 1.0V and up to 650mA.
The architecture is constant frequency at medium to high power outputs where the chip operates in a self-oscillating PWM mode and maximum efficiency is 90%.
At light load, the frequency drops, typical quiescent current is 19μA, and the efficiency is said to stay above 80%.
The chip comes in an 8pin SOIC, and is expected to be used in set-top boxes, TVs, games consoles, cars, industrial modules and white goods.
An evaluation board is available.