Agile Analog Claims Industry First on Customizable 12-bit ADC

As sensing and data become more integral to most modern electronic devices, there is an increased focus on analog-to-digital converter (ADC) performance. To ensure accurate and reliable data collection, the ADC is one of the most important components in the signal chain.

 

Referenced to VDD, VSS, Agile Analog's new agileADC is a traditional charge-redistribution SAR ADC. Image (modified) courtesy of Agile Analog

 

There are many different ADC architectures, each coming with its own unique tradeoffs. This week, Agile Analog announced a new 12-bit SAR ADC with customizable features.

 

What Is a SAR ADC?

One of the most popular ADC architectures that often gets used is the successive approximation register (SAR) ADC.

On a high level, the SAR ADC works by employing a binary search algorithm to match an input voltage with a reference value. A SAR ADC sequentially uses a sample and hold circuit to track the analog input to the ADC. This sampled input is then fed into a comparator along with the input from an internal DAC, the output of which is adjusted in binary increments to get as close as possible to the sampled value. 

 

A SAR ADC block diagram

 

The architecture relies on a feedback loop, where the output of the comparator informs the next binary increment to test against the analog input. Additionally, the circuit relies on clock and timing control circuitry and register control circuitry to facilitate proper operation.

 

The Appeal of 12-bit ADCs

In recent years, there has been a trend toward higher-resolution ADCs, particularly 12-bit ADCs. 

One reason for this is the increased demand for higher accuracy and precision in a wide range of applications. Today, everything from smartphones to wearables has sensing capabilities, making the need for accurate and high-resolution ADCs more ubiquitous than before. 

For many applications, 12-bit ADCs offer a good combination of high resolution and low power consumption. The high resolution allows the devices to capture small changes in input signals with greater accuracy than lower-resolution ADCs. This high-resolution/low-power combination is particularly important in applications where precise measurements are needed for battery-powered electronics, like wearables or smartphones.

 

Agile Brings Customizability to its SAR-based ADC

Agile Analog's new product, called the agileADC, is a charge-redistribution SAR-based ADC that consists of an ADC core, an internal reference generator, an input multiplexer, and a digital controller. Additionally, the device allows users to customize certain features, such as input channels, which can reach up to 16, and sampling rate, which can reach up to 64 MSPS. Each input channel can also be configured to be buffered or unbuffered and support differential or single-ended inputs.

 

agileADC block diagram. Image courtesy of Agile Analog

 

According to Agile Analog, the agileADC features specs that include a SINAD of 69 dB, ENOB of 11.3 bits, and an SNR of up to 70 dB. More details about the chip and how it functions are yet to be released.