Design of a variable width pulse generator feasible for manual or automatic control

A variable width pulse generator featuring more than 4-V peak amplitude and less than 10-ns FWHM is described. In this design the width of the pulses is controlled by means of the control signal slope. Thus, a variable transition time control circuit (TTCC) is also developed, based on the charge and discharge of a capacitor by means of two tunable current sources. Additionally, it is possible to activate/deactivate the pulses when required, therefore allowing the creation of any desired pulse pattern. Furthermore, the implementation presented here can be electronically controlled. In conclusion, due to its versatility, compactness and low cost it can be used in a wide variety of applications.

Synchronous products of rewrite systems (extended version)

We present and formalize a concept of synchronous product for rewrite systems, and also a corresponding concept for general transition systems, used as semantics for the former. A series of examples shows their practical usefulness: for the strategic control of systems, and for modular specification and verification.