Dynamic Delay Check (dyn

Dynamic Delay Check (dyn_delay)

Description

Checks timing delays between two signals and reports nodes with edge delay errors.

The delay is measured between user-specified nodes and a reference node. A timing delay error occurs when the transition time of a signal falls outside the range of refTime + min_time and refTime + max_time, where refTime is the transition time of the reference signal. In other words, a timing delay error occurs when the delay between the signal and the reference signal is outside the range of min_time and max_time.

ref_vhth and vhth parameters are used for triggering rising edge measurements, while ref_vlth and vlth parameters are used for triggering falling edge measurements. For example, a delay measurement from a rising reference signal to a falling signal includes measuring the delay from the time the reference signal crosses ref_vhth to the time the signal crosses vlth.

If the subckt parameter is specified then node and ref_node are considered as local nodes to the specified subcircuit. In other words, node and ref_node will belong to the instances of the specified subcircuit. Only one subckt value can be specified per check, with no wildcard.

If the subckt parameter is not specified, node and ref_node are considered as global nodes with hierarchical names starting from the top level.

The results are written to the dynamic.xml file, which can be viewed in a Web browser.

Syntax

Name dyn_delay parameter=value ...

Parameters

Design check parameters


`node`	`[...]`	Nodes to which the check is applied. Default is none.
`ref_node`		Name of the referenced node.
`min_time`	`(sec)`	Minimum delay between the signal and the reference signal transition.
`max_time`	`(sec)`	Maximum delay between the signal and the reference signal transition.
`edge`	`rise`	Edge type of the signal net. Default is rise.Possible values are rise, fall and both.
`ref_edge`	`rise`	Edge type of the reference signal. Default is rise.Possible values are rise, fall and both.

Digitize parameters


`delay_chk_time`	`0.0 sec`	Delay time checking window.
`vlth`	`0.2 V`	Low voltage threshold for the signal net.
`ref_vlth`	`0.2 V`	Low voltage threshold for the referenced net.
`vhth`	`0.8 V`	High voltage threshold for the signal net.
`ref_vhth`	`0.8 V`	High voltage threshold for the referenced net.

Filtering parameters


`time_window`	`[tstart, tstop] sec`	Time window to which the circuit check is applied. Multiple non-overlapping time windows are supported. Default time window is 0 to tend.
`error_limit`	`10000`	Maximum number of errors reported. Default is 10000.

Wildcard scoping


`subckt`	`none`	Instances of the specified subcircuit to which the check is applied. Default is none.

Spectre Circuit Simulator ReferenceProduct Version 23.1, September 2023