DAC Gives Boost During Power Failure

ANALOG CONTROL
MCP4725 DIGITAL-TO-ANALOG CONVERTER,
MICROCHIP TECHNOLOGY INC.

Loss of data at power failures needn't be an issue anymore, thanks to a new digital-to-analog converter (DAC) with an onboard non-volatile memory.

Known as the MCP4725, the new DAC employs non-volatile EEPROM to recall its settings at power-up. That's a big help in portable applications where the power supply may frequently be switched on and off and would otherwise need to call on the onboard microcontroller for help in the DAC reset process.

“In a power failure, if the data is stored in volatile memory, it disappears,” says Youbok Lee, technical staff engineer for Microchip Technology Inc., manufacturer of the MCP4725. “Non-volatile memory makes it so that when you power down, the values are kept in place. So you don't have to use the resources of the microcontroller and you don't have to add an external EEPROM.”

Microchip engineers say they were able to achieve an industry-first with the incorporation of the EEPROM because of their manufacturing processes. In the past, the company has combined analog and digital into one process on its PIC line of microcontrollers, thus setting the stage for the incorporation of EEPROM onto its analog devices.

Microchip says the new device can be employed in medical equipment, smoke detectors, portable consumer devices, portable test and measurement systems, servers, PCs and virtually anything with a power supply.

“It would be a benefit in applications where you want your power supply to come up as quickly as possible,” says John Austin, senior marketing manager for Microchip. “With an EEPROM, you don't have to wait for the microcontroller to re-program the DAC.”

Moreover, the company's engineers say the new device simplifies design work because it reduces cost, power consumption and physical footprint. “Since I don't have to store that data in an external EEPROM or in my microcontroller, it definitely reduces my requirements for my microcontroller,” Austin says. “It's a cost competitive device that can be used in a lot of applications.”