SI5345 Datasheet, PDF (21/62 Pages) Silicon Laboratories – 10-CHANNEL, ANY-FREQUENCY, ANY-OUTPUT JITTER ATTENUATOR/CLOCK MULTIPLIER

Si5345/44/42
Table 13. Thermal Characteristics
Parameter
Symbol
Test Condition^*
Value
Unit
Si5345-64QFN
Thermal Resistance
Junction to Ambient
_JA
Still Air
Air Flow 1 m/s
22
°C/W
19.4
Thermal Resistance
Junction to Case
Thermal Resistance
Junction to Board
Thermal Resistance
Junction to Top Center
Air Flow 2 m/s
_JC
_JB
_JB
_JT
18.3
9.5
9.4
9.3
0.2
Si5344, Si5342-44QFN
Thermal Resistance
Junction to Ambient
_JA
Still Air
Air Flow 1 m/s
Air Flow 2 m/s
22.3
°C/W
19.4
18.4
Thermal Resistance
_JC
Junction to Case
10.9
Thermal Resistance
_JB
Junction to Board
_JB
Thermal Resistance
_JT
Junction to Top Center
9.3
9.2
0.23
*Note: Based on PCB Dimension: 3” x 4.5”, PCB Thickness: 1.6 mm, PCB Land/Via: 36, Number of Cu Layers: 4.
Rev. 1.0
21