Development of a New Electro-thermal Simulation Tool for RF circuits

More documents

Recommendations

Info

30 2.4. Compact Thermal Model (a) Device intersection. (b) Boundary conditions are applied to the packaged device. Figure 2.18: The studied structure in COMSOL. condition is applied to the rest of the structure. The following results show junction temperature, and heat power passing through cooling surfaces (Tab. 2.1). At this point, Table 2.1: Results of 3D detailed simulation. Tj [ o C] PTop [W] PBot [W] PSide [W] Cool. Top 146.4 100 0 0 Cool. Bot. 157.35 0 100 0 Cool. Side 177.32 0 0 100 Cool. Top&Bot. 109.33 51.75 48.16 0 Cool. Top&Side 122.54 57.13 04 2.53 Cool. Bot&Side 132.87 0 56.6 42.94 the thermal resistances corresponding to the three cooling surfaces Rthtop, Rthbottom, Rthside can be plotted versus the heat flux passing through the surfaces Side & Bottom, Side & Top and Bottom & Top respectively (Fig. 2.19). This is the key point to obtain a control equation for the values of the three resistors. Assuming thermal resistance values evolve linearly (Fig. 2.19), and the boundary conditions are applied as in Fig. 2.18, the variable thermal resistances are defined as follows: Rth_top = Rtop_min + Pside Rth_bottom = Rbottom_min + Pside Rth_side = Rside_min + Ptop αT −T S + Ptotal Pbottom αT −T B Ptotal αB−BS + Ptotal Ptop αB−T B Ptotal αS−T S + Ptotal Pside αS−SB Ptotal (2.51a) (2.51b) (2.51c) The Rtop_min, Rbottom_min and Rside_min are the minimum values of the thermal resistance, i.e., while applying extreme cooling condition on the surfaces: Top, Bottom and
Chapter 2. Thermal models for the electro-thermal simulation 31 (a) Rth_top vs. (PBottom/Ptotal & PSide/Ptotal) (c) Rth_side vs. (PBottom/Ptotal & PTop/Ptotal) (b) Rth_bottom vs. (Ptop/Ptotal & PSide/Ptotal) Figure 2.19: Thermal resistances vs. dissipated heat plots. Side. The factors αT −T S with αT −T B are the slopes of plot in Fig. 2.19a, αB−BT with αB−BS for Fig. 2.19b, and αS−T S with αS−BS in Fig. 2.19c. P is for heat power passing through a given surface. Three equations can express the junction temperature. Tj = Rtop_min + Pside αT −T S + Ptotal Pbottom αT −T B Ptop + Rh_topPtop (2.52a) Ptotal Tj = Rbottom_min + Pside αB−BS + Ptotal Ptop αB−T B Pbottom + Rh_bottomPbottom (2.52b) Ptotal Rside_min + Ptop αS−T S + Pside (2.52c) Tj = Ptotal αS−SB Ptotal Pside + Rh_sidePside In addition, the following equation must be also taken into account: Ptotal = Ptop + Pside + Pbottom (2.53) These control equations give an unique value for Ptop, Pbottom and Pside that satisfy all boundary conditions. Then the new Rth_top, Rth_bottom and Rth_side values are obtained from their definition. However, if boundary conditions are changed on cooling surfaces, a new solution has to be calculated, in order to get a new value for the three thermal resistances. The presented methodology allows obtaining simple BCI CTM, with a few 3D simulations.
Page 1: Tesi di Dottorato Università degli
Page 5 and 6: Preface Thermal interactions set a
Page 7 and 8: Contents v 3.2.2 Processing . . . .
Page 9 and 10: List of Figures vii 2.6 Case for th
Page 11 and 12: List of Figures ix 3.20 Selecting "
Page 13 and 14: List of Figures xi 3.57 Fourth prep
Page 15 and 16: List of Tables 1.1 Comparison betwe
Page 17 and 18: CHAPTER 1 The relevance of the elec
Page 19 and 20: Chapter 1. The relevance of the ele
Page 27 and 28: CHAPTER 2 Thermal models for the el
Page 29 and 30: Chapter 2. Thermal models for the e
Page 45: Chapter 2. Thermal models for the e
Page 55 and 56: Chapter 3. Development of the elect
Page 97 and 98:
Chapter 3. Development of the elect
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
APPENDIX A Design of efficient opti
Page 141 and 142:
Appendix A. Design of efficient opt
Page 143 and 144:
Page 145 and 146:
Page 147 and 148:
Page 149 and 150:
Page 151 and 152:
Page 153 and 154:
List of publications ⋆ F. M. De P
Page 155 and 156:
Bibliography 139 [8] B. Jagannathan
Page 157 and 158:
Bibliography 141 ii. a novel analys
Page 159 and 160:
Bibliography 143 [50] C. C. McAndre
show all

Development of a New Electro-thermal Simulation Tool for RF circuits

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?