A current-steering digital-to-analog converter (DAC) was developed that achieves improved switching times (up to 75% faster) in high-speed (gigahertz), high-resolution (8-14 bits) applications resulting in improvement of spurious free dynamic range (SFDR).
In conventional DACs, the large ratio between current magnitudes of the least significant bit (LSB) and most significant bit (MSB) cells causes differences in response times that create output glitches. The new device utilizes a novel circuit design that drives currents comparable in magnitude to the MSB through the LSB and low-order bit cells, resulting in greatly enhanced switching speeds and minimized glitching, providing enhanced spectral performance (e.g. SFDR).
The technology is amenable to improving the spectra of DACs using CMOS, bipolar, and other process technologies and transistors (III-V and HBT such as SiGe, GaN, GaAs, etc). The approach is suited for any resolution current-steering, gigahertz digital-to-analog converters, either as a standalone application or as subcomponents incorporated into other systems, including wideband radio frequency signal processing and general-purpose baseband communications, instrumentation, radar, and electronic warfare systems.
In addition, this technology advancement is pertinent to both Nyquist rate and Delta-Sigma DACs in both binary and segmented topologies.