OPA1632 Datasheet, PDF (17/30 Pages) Texas Instruments – High-Perfomance, Fully-Differential AUDIO OP AMP

www.ti.com
OPA1632
SBOS286C – DECEMBER 2003 – REVISED OCTOBER 2015
Layout Guidelines (continued)
The PowerPAD package allows for both assembly and thermal management in one manufacturing operation.
During the surface-mount solder operation (when the leads are being soldered), the thermal pad must be
soldered to a copper area underneath the package. Through the use of thermal paths within this copper area,
heat can be conducted away from the package into either a ground plane or other heat-dissipating device.
Soldering the PowerPAD to the printed circuit board (PCB) is always required, even with applications that have
low power dissipation. It provides the necessary thermal and mechanical connection between the lead frame die
pad and the PCB.
10.1.2 Power Dissipation And Thermal Considerations
The OPA1632 does not have thermal shutdown protection. Take care to assure that the maximum junction
temperature is not exceeded. Excessive junction temperature can degrade performance or cause permanent
damage. For best performance and reliability, assure that the junction temperature does not exceed 125°C.
The thermal characteristics of the device are dictated by the package and the circuit board. Maximum power
dissipation for a given package can be calculated using the following formula:
T -T
P
= ^Max
A
DMax
q_JA
where:
• P_DMax is the maximum power dissipation in the amplifier (W)
• T_Max is the absolute maximum junction temperature (°C)
• T_A is the ambient temperature (°C)
• θ_JA = θ_JC + θ_CA
• θ_JC is the thermal coefficient from the silicon junctions to the case (°C/W)
• θ_CA is the thermal coefficient from the case to ambient air (°C/W)
For systems where heat dissipation is more critical, the OPA1632 is offered in an MSOP-8 with PowerPAD. The
thermal coefficient for the MSOP PowerPAD (DGN) package is substantially improved over the traditional SO
package. Maximum power dissipation levels are depicted in Figure 19 for the two packages. The data for the
DGN package assume a board layout that follows the PowerPAD layout guidelines.
MAXIMUM POWER DISSIPATION
vs AMBIENT TEMPERATURE
3.5
q_JA = 170°C/W for SO-8 (D)
3.0
q_JA = 58.4°C/W for MSOP-8 (DGN)
T_J = +150°C
No Airflow
2.5
MSOP-8 (DGN) Package
2.0
1.5
1.0
SO-8 (D) Package
0.5
0
-40
-15
10
35
60
85
Ambient Temperature (°C)
Figure 19. Maximum Power Dissipation vs Ambient Temperature
Copyright © 2003–2015, Texas Instruments Incorporated
Product Folder Links: OPA1632
Submit Documentation Feedback
17