Maxim’s Small Step-Down DC-DC Converters Deliver 500mA and Integrate Feedback Network in SC70
Maxim Integrated Products Inc. introduced the MAX8640Y/MAX8640Z, which the company claims is the industry's smallest 500mA, high-efficiency step-down dc-dc converters in a tiny SC70 package. The devices are suitable for applications where small size, high efficiency, and low output ripple are priorities. They utilize a proprietary switching scheme to reduce external component size and draw only 24µA of quiescent current, thus providing impressive light-load efficiency.
The combination of small size and high efficiency makes the MAX8640Y/MAX8640Z optimal for generating low-voltage microprocessor core supplies for cell phones, smartphones, digital cameras, and similar portable applications powered by a single-cell Li+ or 3-cell NiMH/NiCd batteries. Factory-preset output voltages from 0.8 to 2.5V eliminate external feedback-network components.
The high integration of the MAX8640Y/MAX8640Z enables a small total solution size (13.4mm2) vs. the conventional 35mm2 of SOT23 solutions. These devices integrate a synchronous rectifier, which eliminates the need for an external diode and improves efficiency, especially at low output voltages. The devices also feature low output ripple at all loads, ultra-fast line- and load-transient response, and fast internal soft-start, which eliminates in rush current.
The MAX8640Y/MAX8640Z are available in 2mm x 2.1mm SC70 and 1mm x 1.5mm microDFN packages. They are specified for the extended temperature range (-40 to +85°C). Prices start at $1.58 (1000-up, FOB USA).
