Digital to Analog Converter (DAC or D-to-A) is a device that converts digital codes to an analog signal. There are many categories of DACs. Some of these categories include sigma-delta DACs, pulse width modulators, interpolating and high speed DACs. In this paper the focus will be on the interpolating and high speed DACs.

The Σ-Δ ADC and DAC architecture is the ultimate extension of the oversampling concept and is the architecture of choice for most voiceband and audio signal processing data converter applications.

• An analog filter is required at the output of the DAC to select the desired image signal and attenuate the undesired images • This analog filter is called a

2012年8月20日 · Digital-to-analog converters (DACs) convert digital data to analog voltage or current in applications such as instrumentation and wireless communications. A DAC's output frequency generally ranges from DC to less than f S /2, where f S is the input-updating frequency.

DAC用于将位形式的数字样本转换为电流或电压的模拟波形。 简而言之，DAC用于从数字信号重建模拟信号。 从数字信号重建模拟信号的过程如下。 首先，将表示期望模拟信号的一系列数字样本输入到 DAC 中。 接下来，DAC通过使用由数字样本加权的重建波形来输出数字样本，从而执行模拟重建。 最后，使用模拟滤波器来平滑输出响应。 模拟滤波器用于从输出信号中去除不需要的信号（称为镜像信号）。 重建波形决定了数模转换器（DAC）在时域和频域的输出响应。 在 …

2021年8月24日 · I have been reading the theory behind digital to analog converters. I'm still very confused on what causes images to appear in the frequency domain. For example, if I was using a DAC that was producing a 1 MHz signal at 40 MHz sample rate. I notice that I have harmonics in the frequency domain at 39 MHz and 41 MHz. what causes that to happen?

The DAC5674 is a 14-bit resolution high-speed digital-to-analog converter (DAC) with integrated 4x-interpolation filter, on-board clock multiplier, and on-chip voltage reference. The device has been designed for high-speed digital data transmission in wired and wireless communication systems, high-frequency direct-digital synthesis (DDS) and ...

2019年7月22日 · Exploring image creation on cathode ray (analogue) oscilloscopes with single and dual digital to analogue converter (DAC) outputs in CircuitPython using the Circuit Playground Express and PyGamer boards.

In the typical case where the DAC uses a zero-order-hold (non-return-to-zero) pulse, these images are only attenuated by a sinc filter. In this work we present a technique to implement an analog first-order-hold filter to greatly improve the image rejection of the DAC output signal.

The applet above demonstrates harmonic images (red) and spurs (blue) in an idealized DAC output. Images are located at N*F s + M*F o, where M=+/-1. Without external filtering image amplitudes roll off as sin(x)/x where x = pi*F o / F s. Spurious 2nd or 3rd harmonics of the fundamental are assumed to result from