OPA541: can the metal package of the OPA541AM could be grounded ?

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Replies: 1

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Part Number: OPA541

Good morning,

We are using OPA541AM (8pins TO3)

Here is the application design :

https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/14/driver.jpg

We use 6 OPA541AM driving inductive charge with the same heatsink

as the heatsink is totaly isolated, It seems that we have electrostatic problem due to the heatsink witch is aircooled

all the metal package are electricaly connected together via the heatsink.

first question  : Can we connect the metal package to PGND without damage of the parts ?

second question is-it better to connect NC pins (2 and 7) to PGND ?

Thanks for your quick answer.

Gilbert DURAND

1 Reply

  • Hello Gilbert,

    The original OPA541 datasheet from the 1990s states "No insulating hardware is required when using the TO-3 package. Since mica and other similar insulators typically add approximately 0.7°C/W thermal resistance, their elimination significantly improves thermal performance." Therefore, this indicates that the metal TO-3 package has no electrical connection to the OPA541 internal electronics. You should be able to connect the common heatsink, to which the OPA541 TO-3 packages are mounted, to ground or whatever potential is reasonable with no effect on the Op amps.

    Pins 2 and 7 have internal no connection (NC) and can be left floating, grounded or tired to whatever is convenient.

    Regards, Thomas

    Precision Amplifiers Applications Engineering