L4979DTR-E Datasheet, PDF (16/22 Pages) STMicroelectronics – Low drop voltage regulator

Package and PCB thermal data
Equation 2: pulse calculation formula
ZTH_ = RTH   + ZTHtp1 – 
where  = t_P/T
Figure 12. Thermal fitting model of V_reg in SO-20
L4979D, L4979MD
Table 12.
SO-20 thermal parameter
Area (cm²)
R1 (°C/W)
R2 (°C/W)
R3 (°C/W)
R4 (°C/W)
R5 (°C/W)
R6 (°C/W)
C1 (W.s/°C)
C2 (W.s/°C)
C3 (W.s/°C)
C4 (W.s/°C)
C5 (W.s/°C)
C6 (W.s/°C)
Footprint
4
2
2.2
10
15
35
0.0003
0.0025
0.015
0.15
1.5
4
*$3*&)7
2
18
7
16/22
Doc ID 10262 Rev 9