August 2021

Model of the Month

Precharge-type phase-only detector

Check out how to model a precharge-type phase-only detector (PD), which is suitable for aligning two clocks with a zero phase offset in a DLL. This PD was first published by S. Sidiropoulos, et al. in 2000.

Tip of the Month

Dumping the waveforms of selected signals only

Learn the various options available for the dump primitive or $xmodel_dumpvars() command to dump just the waveforms of specific signals or signals contained in specific instances only.

Primitive of the Month

xbit_to_xreal_var

This primitive converts an xbit-type input to an xreal-type output, of which logic-1 and logic-0 levels can be varied with the level1 and level0 input signals.

XMODEL Release Updates

2021.08 Release

This release adds many improvements and bug fixes including the improved speed of the stline primitive and the --select option for the sparam_to_tline utility to support partial selection of ports.

Latest Issues

March 2025

Silicon Photonics Simulation with XMODEL, Measuring I-V Curves, and More

February 2025

Catching Elusive Voltage Spikes with Assertions, Modeling VCO with Extra Digital Inputs, and More

January 2025

Modeling Delta-Sigma Digital-to-Analog Converters, XMODEL at DVCon US, and More

December 2024

Modeling Mixed-Signal Processing-in-Memory Circuits, Filtering Phase Noise, and More

November 2024

Modeling a Digital LDO, Tips on Modeling High-Pass Filters, and More