Sigma–Delta ADCs–for Higher Accuracy from More Bits When speed is not as critical, the oversampling and noise shaping of a sigma-delta ADC affords very high precision.
What is high speed ADC?
Analog Devices high speed A/D converters (ADCs) offer the best performance and highest sampling speed in the market. The product offerings include high IF ADCs (10 MSPS to 125 MSPS), low IF ADCs (125 MSPS to 1 GSPS), integrated receivers, and wideband ADCs (>1 GSPS).
Why it is called flash ADC?
Abstract: Flash analog-to-digital converters, also known as parallel ADCs, are the fastest way to convert an analog signal to a digital signal. Flash ADCs are ideal for applications requiring very large bandwidth, but they consume more power than other ADC architectures and are generally limited to 8-bit resolution.
Why is Flash ADC fastest?
1)It is the fastest type of ADC because the conversion is performed simultaneously through a set of comparators, hence referred as flash type ADC. Typical conversion time is 100ns or less.
Which type of ADC is most accurate?
“LTC2378-20 is the first 20bit SAR ADC on the market offering ±0.5ppm typical integral nonlinearity [INL] error with a guaranteed specification of 2ppm maximum over temperature, making it the most accurate ADC in the industry.
What is fastest ADC and why?
The flash ADC is the fastest type available. A flash ADC uses comparators, one per voltage step, and a string of resistors. A 4-bit ADC will have 16 comparators, an 8-bit ADC will have 256 comparators.
What are the advantages and disadvantages of flash ADC?
Block diagram of Flash ADC The advantage of this converter is the speed with which one conversion can take place. The disadvantage of the Flash ADC is the area and power requirements of the 2 N-1 comparators. The speed is limited by the switching of the comparators and the digital logic.
What is the disadvantage of flash ADC?
The main disadvantage of flash ADC is that it need large area and dissipate large amount of power. To overcome this complexity number of comparators are reducing by using multiplexers. Here the multiplexers are used to generate reference voltages.
Which type of ADC has high resolution?
Delta-sigma ADCs work by over-sampling the signals far higher than the selected sample rate. The DSP then creates a high-resolution data stream from this over-sampled data at the rate that the user has selected. This over-sampling can be up to hundreds of times higher than the selected sample rate.
What is the reference voltage of a flash ADC?
Figure 1 shows a typical flash ADC block diagram. For an N-bit converter, the circuit employs 2 N -1 comparators. A resistive-divider with 2 N resistors provides the reference voltage. The reference voltage for each comparator is one least significant bit (LSB) greater than the reference voltage for the comparator immediately below it.
Why are flash ADCs not suitable for high frequency applications?
Flash ADCs are suitable for applications requiring very large bandwidths. However, these converters consume considerable power, have relatively low resolution, and can be quite expensive. This limits them to high-frequency applications that typically cannot be addressed any other way.
What is the architecture of a flash ADC?
Flash ADC architecture. If the analog input is between VX4 and VX5, comparators X1 through X4 produce 1s and the remaining comparators produce 0s. This architecture is known as thermometer code encoding.
Which is better a flash converter or an ADC?
Flash ADCs are ideal for applications requiring very large bandwidth, but they consume more power than other ADC architectures and are generally limited to 8-bit resolution. This tutorial will discuss flash converters and compare them with other converter types.