A RAMDAC is a combination of three fast digital-to-analog converters (DACs) with a small static random-access memory (SRAM) used in computer graphics display controllers or video cards to store the color palette and to generate the analog signals to drive a color monitor. The logical color number from the display memory is fed into the address inputs of the SRAM to select a palette entry to appear on the data output of the SRAM. This entry is composed of three separate values corresponding to the three components of the desired physical color. Each component value is fed to a separate DAC, whose analog output goes to the monitor, and ultimately to one of its three electron guns.
A Brooktree RAMDAC
IMS G171 RAMDAC on the VGA board
Digital-to-analog converter
In electronics, a digital-to-analog converter is a system that converts a digital signal into an analog signal. An analog-to-digital converter (ADC) performs the reverse function.
8-channel Cirrus Logic CS4382 digital-to-analog converter as used in a sound card.
Top-loading CD player (top) and external digital-to-analog converter (bottom) from the same company.
An external DAC (1990s) from Audio Alchemy as an add-on for CD players, having only about 12 cm width, intended to improve the sound of older or less expensive players.