The example is only to give the basic conversion idea. Commercial DAC, such as the DAC 0808 shown in Fig. 13.18b are readily available. The DAC 0808 is an 8-bit converter which will give an output resolution or accuracy of 1 in (28 − 1) (−1 is because the first number is zero leaving 255 steps) or an accuracy of ±0.39 percent. For higher accuracy analog signals a 12-bit commercial DAC would be used (±0.025 percent accuracy).