Analog Devices, Inc. (ADI) introduced what it describes as one of the industry’s smallest buck-boost regulators – and said to be the first to support switching frequencies at speeds up to 2.5 MHz. Designed to regulate voltages above and below the battery output voltage in portable electronics, ADI’s ADP2503 and ADP2504 step-up/step-down dc-dc regulators incorporate a patent-pending architecture that delivers seamless mode transitions.
The ultra-fast switching speed of the new regulators is said to allow designers to use low-cost multilayer inductors that are half the size of other solutions. In addition, the total external component count has been reduced to three, resulting in a total PCB area of less than 13 mm² and a height of less than 1mm, making the solution well suited for space constrained applications such as wireless handsets, digital still cameras, portable audio players and USB-powered consumer and industrial devices.
"Many lithium-battery-powered devices require voltage rails in the 2.8-V to 3.6V range for RF, audio, or motor applications. The ADP2503 and ADP2504 are ideal regulators to provide these voltages when board area and efficiency are important," said Arcadio Leon, Marketing Director for Portable Power Products, Analog Devices.
The ADP2503 and ADP2504 regulators are based on ADI’s new proprietary current-mode buck-boost architecture, achieving glitchless mode transitions and outstanding transient performance across line and load. This high level of output stability is critical for powering sensitive analog and digital circuitry. The devices also feature what is described as one of the industry’s lowest no-load quiescent current (Iq) levels – 38 µA in power-save mode –which extends stand-by time in portable electronics and/or increases the power budget for the inclusion of additional features. The proprietary H-Bridge buck-boost architecture improves the efficiency by more than 10% versus legacy cascaded boost-buck architectures by reducing switching losses.
The ADP2503 and ADP2504 operate at input voltages ranging from 2.3 and 5.5V, which meets the requirements for single Li-Ion, Li-Ion polymer cell and multiple alkaline/NiMH cell applications. Fixed output voltages range from 2.8 to 5V.
The ADP2503 and ADP2504 are available now in sample quantities and come housed in a 10-lead 3 x 3mm thin LFCSP package. The buck-boost regulators are priced at $1.40 per unit in 1,000-unit quantities.