Overview. Motivation (Kevin) Thermal issues (Kevin) Power modeling (David) Thermal management (David) Optimal DTM (Lev) Clustering (Antonio) Power distribution (David) What current chips do (Lev) HotSpot and sensors (Kevin). Pentium 4 Observations.
T_ambDynamic compact thermal model
V temp (T)
I power (P)
R thermal resistance (Rth)
C thermal capacitance (Cth)
RC time constant (Rth Cth)
Kirchoff Current Law
differential eq. I = C · dV/dt + V/R
thermal domain P = Cth · dT/dt + T/Rth
where T = T_hot – T_amb
At higher granularities of P, Rth, Cth
P, T are vectors and Rth, Cth are circuit matrices
Now: what can we do with HotSpot?
Peripheral spreader nodes
Interface + Sink
Interface material(not shown)
We are not well-versed on sensor design; the following is a digest of information we have been able to collect from industry sources and the research literature.
(In approx. order of increasing ease to build)
PTAT – Proportional to Absolute Temperature
Syal, Lee, Ivanov, Altet, Online Testing Workshop, 2001
Schematics of Delta Vgs Current Reference (left) Generator and Delay Cell (right)
P: 10s of mW