4.2 User Defined Measurements

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4.2 User Defined Measurements

• An alternative to SPICE descriptions
• Provides flexibility requested by Arpad Muranyi
• Provides high abstraction requested by Ian Dodd
• Measurements created through categories
• Number of categories is the same for all
  measurements
• Specific calculation methods left up to tool
• Partial listing of categories (concept)
• Name
• Type
• Location
• Reference
• Domain
• Unit
• Duration
• Load
• Relation (?)

identifier standard for certain measurements
event (one-shot), continuous
Node Declarations, Pin, etc. pointer
GND, POWER, External Ref, Pin, Node Decl.
Time, Frequency
Volts, Amps, Seconds, Hertz, etc.
Event, (time in seconds)
Value and units may need load reference
Placeholder for equation expansion
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4.2 User Defined Measurements

• Tools can require certain names/list contents
• Example Overshoot (name) as voltage (unit) in
  time domain (domain) at (location) above
  (reference)
• May need to allow multiple entries
• Example Load Load reference three times for
  PCI
• Advantages
• Highly generic
• Can likely be expressed in AMS as well as SPICE
• Note that above etc. are already VHDL-AMS
  concepts
• SPICE min can be developed from abstract
  equations
• Allows expression of required IBIS measurements
• Disadvantages
• Resembles current IBIS
• May require periodic expansion for new
  technologies
• Unwieldy, not particularly compact

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Feasibility Requirements

• Acceptable to tools?
• Can data expressed this way be processed by
  todays tools outside of AMS?
• Clearly understandable to users?
• Categories are complete?
• Need someone to review all SPICE measurement
  options to ensure all covered by category listing
• Need someone to review all IBIS measurement data
  for same
• Apologies to Immanuel Kant