THS6032 Datasheet, PDF (17/31 Pages) Texas Instruments – LOW-POWER ADSL CENTRAL-OFFICE LINE DRIVER

THS6032
LOW-POWER ADSL CENTRAL-OFFICE LINE DRIVER
SLOS233C – APRIL1999 – REVISED MARCH 2000
APPLICATION INFORMATION
thermal information (continued)
The actual thermal performance achieved with the THS6032 in its PowerPAD package depends on the
application. In the previous example, if the size of the internal ground plane is approximately 3 inches × 3 inches,
then the expected thermal coefficient, θ_JA, is about 21.5°C/W for the DWP package and 37.8°C/W for the GQE
package. For a given θ_JA, the maximum power dissipation is shown in Figure 40 and is calculated by the
following formula:
ǒ Ǔ PD +
TMAX–TA
q_JA
Where:
P_D = Maximum power dissipation of THS6032 (watts)
T_MAX = Absolute maximum junction temperature (150°C)
T_A = Free-ambient air temperature (°C)
θ_JA = θ_JC + θ_CA
θ_JC = Thermal coefficient from junction to case (DWP =0.37°C/W; GQE = 4.56°C/W)
θ_CA = Thermal coefficient from case to ambient
MAXIMUM POWER DISSIPATION
vs
FREE-AIR TEMPERATURE
9
TJ = 150°C
8
PCB Size = 3” x 3”
No Air Flow
7
6
5
GQE
DWP
θ_JA = 21.5°C/W
2 oz Trace and
Copper Pad
with Solder
4
3
DWP
2 ^θJA ^{= 43.9°C/W}
2 oz Trace and Copper Pad
1 ^{without Solder}
0
–40 –20 0
20 40 60 80 100
TA – Free-Air Temperature – °C
Figure 40. Maximum Power Dissipation vs Free-Air Temperature
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