Part Number: OPA564
Hello Team,
Godo day.
My Customer is looking for details about the thermal resistance of the OPA564 DWD version:
- JA is junction to ambient, using Thermalloy part no. 65810, I can't find any information about this heatsink. What is the expected thermal resistance of this heatsink?
(14) Thermal modeling of the DWD-20 package was done based on a 1-inch AAVID Thermalloy heatsink (Thermalloy part no. 65810).
Regards,
Renan
Hi Renan,
The OPA564 was in development close to 20 years ago and it looks like ite 65810 heatsink was discontinued since then by the manufacturer. I found some some bits of information about the heatsink online, but nothing complete. One Aavid catalog made mention of the 65810 heatsink:
https://www.mouser.com/catalog/supplier/library/pdf/Aavidselectionguide.pdf
"EXAMPLE: Extrusion #65810 has a perimeter of 26.2 in2 /in and will be cut to 4.0” long.The air flow is 600 LFM.Therefore, the performance factor is 18.70 (from the table using 600 LFM and 4.0”) and its θsa is 0.71 °C/W (18.70/26.2)"
Elsewhere, in a somewhat more cryptic document I found more specifications for the 65810 heatsink:
In it, it lists the following information:
65810 26.2 in 2 /in 1.9lb/ft 2.7°C/W/3in
Most important is the last number 2.7°C/W/3in, which I believe is the convected air thermal resistance for a 3" length of the 65810 heatsink. It states in the Aavid
manual:
Therefore, for a 1" length the correction factor is 1.8x. Multiplying the 2.7°C/W/3in number by 1.8x gives a 4.86 °C/W for a 1" length of the 68510 heatsink material.
Regards, Thomas
Precision Amplifiers Applications Engineering
