HEC Electronics Chain HEC chain-2000 Spice model Analytical model HECPAS Review MPI Feb.12 2009 L. Kurchaninov HEC Electronics Chain HEC chain-2000 Spice model Analytical model Spice vs. Analytics HEC chain-2010 PA Spice model Validation tests HEC mock-up

MiniFCAL, TRIUMF 31 Oct. 2008 L. Kurchaninov HEC Chain-2000

MiniFCAL, TRIUMF 31 Oct. 2008 L. Kurchaninov Spice Model All active components are Laplace functions with parameters taken from measurements Two models: for warm and for cold A number of versions: beam tests, ATLAS Cables are “lossy”, but frequency independent Spice is used as a numerical calculator to generate waveforms Model was used to study effects of various components to signal shape and amplitude (e.g. strip line stray capacitance, decoupling caps, etc.) Cross-check analytical model

HECPAS Review MPI Feb.12 2009 L. Kurchaninov Analytical Model ATLAS HEC Note-109 Modeling of the HEC Electronics Chain wwwatlas.mppmu.mpg.de/HEC/notes.html Model functions are pole-zero combinations (in s-domain) Skin effect in cables is approximated by 1Z-2P function Model adjustable to reproduce shapes within ±1% Used for signal reconstruction in beam tests

+ - Spice vs. Analytics Feature Spice Analytic Detail description HECPAS Review MPI Feb.12 2009 L. Kurchaninov Spice vs. Analytics Feature Spice Analytic Detail description + - Reflections Skin effect Noise calcs

HEC Chain-2010 Faster timing requires better models HECPAS Review MPI Feb.12 2009 L. Kurchaninov HEC Chain-2010 Faster timing requires better models Both models are useful: SPICE: detail modeling, debugging, failures Analytic: signal reconstruction functions and algorithms Important for analytics Better cable model Important for Spice Skin-effect in cables: not trivial up to my knowledge HEC impedance Xtalk leak and shapes Noise calculations: to xcheck analytic model

GaAs Spice Model Was missing for GaAs PA. First built then modeled HECPAS Review MPI Feb.12 2009 L. Kurchaninov GaAs Spice Model Was missing for GaAs PA. First built then modeled Make sense before production starts Do we need full Spice? Transfer function vs. in/out load, LV, … Oscillations margin Power vs. signal rate Warm-cold performance Identify causes of radiation degradation Could be time and manpower consuming

HECPAS Review MPI Feb.12 2009 L. Kurchaninov Validation Tests Design stage requires various tests, sometime beyond actual practical needs All lab tests at design stage (1996) were done up to “board level” with cable-capacitance input load. OK to validate design, not enough to validate system. System tests done with preproduction batch Was not tested in 1996-97 (and not tested up to date): Response vs. signal rate estimations show no effect for LHC Shape vs. amplitude at 0.1% level done later with calib pulses at 1% level Full-range temperature dependence mostly of academic interest

HECPAS Review MPI Feb.12 2009 L. Kurchaninov HEC Mock-up Measurements of transfer function and noise at ~ns shaping requires actual input load. Can be done with a mockup To cover full range of HEC cable length and Cd To represent HEC shielding and grounding