Digital ICs/DSP: Programmable Clock Generators Offer In-System Configuration

The first devices coming from the ispClock family of in-system programmable clock generator chips combine a high-performance clock generator with a flexible, universal fan-out buffer (UFB). The clock generators in the 10-output ispClock5510 and 20-output ispClock5520 can provide up to five clock frequencies ranging from 10 to 320 MHz. The UFB can drive up to 20 clock nets using either single-ended or differential signaling, with individual output control for improved signal and timing integrity. The UFB has a maximum pin-to-pin skew of 50 ps, while the maximum cycle-cycle (peak-peak) output jitter is less than 100 ps. Housed in a 100-pin TQFP, the ispClock5520 sells for $18.25 each in 1000-unit lots. The PACsystemCLK5520 EV kit costs $349.