Texas Instruments CD74ACT297

the cd74act297 provides a simple cost-effective solution to high-accuracy digital phase-locked-loop applications. this device contains all the necessary circuits with the exception of the divide-by-n counter to build first-order phase-locked loops as shown in figure 1. both exclusive-or phase detectors (xorpds) and edge-controlled (ecpd) phase detectors are provided for maximum flexibility. proper partitioning of the loop function with many of the building blocks external to the package makes it easy for the designer to incorporate ripple cancellation or to cascade to higher-order phase-locked loops. the length of the up/down k counter is digitally programmable according to the k-counter function table. view all in datasheet