5532 in SO16

[svenstad]

The op amp 5532 is available, not only in the normal 8-pin packages, but also in a SO-16 package.
What is the rationale behind the 16-pin version? Who wants a larger package?

[magic]

AFAIK only Signetics and Philips made them. Signetics, because life wasn't easy in the late '70s. Philips, for existing customers presumably.

This is a Signetics NE5532 die on top of SO8 package, oriented to match the pinout. It simply wouldn't fit, but it fits the larger wide body SO16 package below. The other die is a later Philips NE5532 (same as here), which was available in SO8. They had to cram things more densely and tweak the layout to make it narrow.

[Kleinstein]

The 5532 gets quite warm, especially if driving a significant load or high supply voltage (like +-18V). The larger case can dissipate heat better. The exposed pad cases are the more modern alternative for modern chips.