Sunnyvale, Calif. Maxim Integrated Products has introduced the DS4422/DS4424 low-cost, dual-/quad-channel, sink/source current DACs. These I2C-controlled, 7-bit current DACs feature two (DS4422)/four (DS4424) output channels that are designed for power-supply margining and adjustment.
Each output channel provides control of a dc/dc power supply by sinking or sourcing current directly into the power supply's feedback node. This control technique allows existing power supply designs to be margined and adjusted with minimal redesign, making the DS4422/DS4424 devices well-suited for servers, video processing cards, and other dc/dc power-supply applications.
The DS4422/DS4424 devices power-up in a neutral (or zero-current) output condition to minimize system-startup overhead requirements and allow the power-supply feedback resistors to perform in a standard manner. These DACs use an external resistor to program the full-scale current for each output from 50 microamps to 200 microamps with ±6% accuracy. The I2C bus can then be used to linearly set the output currents to any of the 127 sink or 127 source steps up to the maximum value. Two address inputs allow up to four devices or sixteen separate supplies to be controlled on a single I2C bus.
The DACs are fully specified over the -40°C to +85°C extended temperature range. The DS4422/DS4424 devices are available in a 3 x 3-mm, 14-pin TDFN package.
Prices: Starts at $0.53 for the DS4422 and $0.67 for the DS4424 in quantities of 10,000-up, FOB USA.
Maxim Integrated Products , 1-800-998-8800, www.maxim-ic.com