Linear Technology introduced the LTC1628, the world's first 2-phase current mode switching regulator. The LTC1628 delivers output regulation of 0.2% over line and load variations and uses a unique 2-phase switching technique to increase efficiency, reduce EMI, and lower capacitance requirements. These and other features enable the LTC1628 to shrink design size and extend battery life in applications such as notebook computers, PDAs, handheld terminals and automotive electronics.

Unlike traditional single-phase dual-output switching regulators, the LTC1628 interleaves the current pulses coming from the switches by operating its switch drivers 180 degrees out of phase. This minimizes the overlap time when the current pulses add together, thus substantially reducing RMS input current. As a result, the 2-phase technique decreases input capacitance ESR requirements by 50% compared to single-phase regulators (which allows the use of fewer and less expensive input capacitors), reduces radiated and conducted EMI, and improves efficiency.

"Because power losses are proportional to the square of input current, the LTC1628's 2-phase operation reduces input path power loss by a factor of 4," said Afshin Odabaee, Product Marketing Engineer, Linear Technology. "This translates into longer operating time for battery powered products."

The LTC1628 also provides OPTI-LOOP compensation, enabling optimization of transient response with minimal output capacitance. Protection circuitry includes foldback current limiting, a defeatable short-circuit latch off and over voltage soft-latch that protect the part, system, and CPU from damage. It also features 150kHz to 300kHz fixed frequency operation and contains 5V and 3.3V linear standby regulators.

This is not actually "the world's first 2-phase current mode switching regulator." It missed that title by a few weeks, being beaten by a part that probably more accurately dubs the architecture "push-pull." Nevertheless this product is extremely significant because of the very tight tolerance on the output voltage, which you can read to be either within 0.2% or ý1%. Not many applications require the supply voltage to be so well controlled and those that do may be willing to pay the premium for such a part.