(Zero latency Delta Sigma)
Even if a high-precision A/D converter is used, the system accuracy cannot be improved unless the sensor output signal is sampled with high accuracy.
However, it is not easy to realize high precision sampling at the beginning of acquisition of the A/D converter since signal swing called "kickback" occurs.
"ZDS" resolves this problem.
High accurate sampling is easily achieved with a ZDS A/D converter.
Small Input Capacitance = Small Kickback
With an SAR A/D converter, its input capacitance increases as the accuracy of the A/D converter become high, and the kickback level increases.
A ZDS A/D converter makes high precision sampling easier because the input capacitance and the kickback level are lower than an SAR A/D converter.
Long Acquisition Time = Long Recovery Time from Kickback
An SAR A/D converter cannot execute conversion and acquisition at the same time.
Therefore, the faster the response of the A/D converter, the shorter the acquisition time becomes.
A ZDS A/D converter realizes executing acquisition during conversion. In other words, the A/D converter increases the recovery time from kickback while keeping fast response ability, enabling high precision sampling that is essential for high accuracy system.
(Zero latency Delta Sigma with Noise Suppression)
Even if a low-noise A/D converter is used, system noise level cannot be improved unless the input signal noise is reduced. However, it is not easy to generate low noise analog signals with a system that accomplishes high speed response performance.
"ZDS-NS" resolves this problem.
ZDS-NS A/D converter realizes high-speed response while suppressing input signal noise.
Frequency Response Gain of ZDS-NS Digital Filter
The magnitude plot of the ZDS-NS digital filter is shown here.
Since the A/D conversion of ZDS-NS is executed by over sampling that is in the same way as ΔΣ, high frequency noise components up to 10 MHz (* 1) included in the analog input signal are also converted and attenuated by the integrated digital filter. Furthermore, noise suppression effect can be improved by increasing the number of over sampling.
(*1) It is proportional to clock frequency.
ZDS-NS can suppress noise included in the input signal while maintain fast response, realizing both low-noise and high speed response performances on the system.
General Purpose Analog Front End
The general-purpose analog front end is an A/D converter with built-in peripheral circuits such as programmable gain amplifier.
With a general-purpose analog front end, AKM makes your system smaller, faster and more accurate.