Digipots operate from 1.7-5.5V single power supply

Maxim Integrated Products is rolling out a family of dual, 256-tap, volatile digital potentiometers that operate from a single 1.7V to 5.5V power supply, which makes them suitable for replacing mechanical potentiometers and DACs in power-sensitive applications.

With unique features such as a small package size, low operating voltage, and low supply current, the MAX5391/MAX5392/MAX5393 are well-positioned to serve the portable consumer and industrial battery-backup markets. Suitable applications include LCD calibration, volume control, system circuit calibration and trim, amplifier offset, and gain and bias control.

Designers of low-voltage (less than 2.3V) systems, such as industrial battery-backup or portable consumer applications, have previously used mechanical potentiometers or DACs because they can operate from 1.8V. These low-voltage devices allow system designers to meet tight power-consumption specs; however, their use has come at a cost. With mechanical potentiometers, calibration is labor intensive and prone to error, as it typically involves analog adjustments using a screwdriver.

Digital potentiometers have many advantages over their mechanical counterparts: they enable processor control and programmability, they guarantee greater reliability and accuracy, and they offer packaging options that facilitate automatic assembly. In short, they streamline the manufacturing process by eliminating the need for expensive and error-prone manual adjustments. However, designers have been forced to forgo the benefits of digital potentiometers in order to meet the stringent power-consumption requirements of low-voltage systems.

"The MAX5391-MAX5393 bring digital control and calibration to low-voltage systems," explained Jeremy Tole, Maxim's director of business development for data converters. "They are the industry's first digital potentiometers to operate from a voltage as low as 1.7V. This capability, along with a small TQFN package, makes this family a space-saving alternative to mechanical potentiometers and some DACs in portable consumer and industrial battery-backup applications. Designers can now enjoy all of the benefits of digital potentiometers while still meeting their power-consumption specs."

The MAX5391—MAX5393 include two digital potentiometers in a voltage-divider configuration. The devices have a low 5ppm/°C ratiometric temperature coefficient and come in three different end-to-end resistance values of 10-, 50- and 100k?. SPI-compatible and I? C digital control interfaces are available.

The MAX5391 device is offered in an ultrasmall (3mm x 3mm) 16-pin TQFN package; the MAX5392/MAX5393 are available in 16-/14-pin TSSOP packages. All devices are fully specified over the -40°C to +125°C automotive temperature range.

Prices start at $1.32 (1000-up, FOB USA). Samples and evaluation kits are available now.