| 摘要 |
A true N-bit digital-to-analog converter (DAC), i.e. a DAC the absolute accuracy error of which is less than 1 LSB (or +/-1/2 LSB), can be composed of easy obtainable and low-priced components. The DAC distinguishes a very fast, highly accurate, high resolution conversion of a digital input code into an equivalent voltage or current. Two or more DACs are cascaded in order to attain a high resolution. Only one ROM and an associated DAC are necessary to obtain an accuracy error of less than 1 LSB, in consequence of the increased resolution. The final trimming can be conducted in packaged form of the device through the ROM programming. For example, a true 16-bit DAC can be composed of three equal true 8-bit DACs, wherein their absolute accuracy error must be less than 0.992 LSB. A ROM with the storage capacity of only 256 bytes is necessary.
|
