Playing around with a dead HP Kittyhawk hard drive, a tiny drive from 1992.
There is a Philips TDA5340 chip in a 48 pin TQFP.
However that part number gets me a part in a different package and obviously not the right function. Some sort of radio transmitter.
Closest I could find is TDA5345HT, a spindle and voice coil driver, but in a larger pin count package, but the description fits. It's right next to the connector that goes to the drive itself.
Did they just reuse a part number?
It's hard getting any data for most of the chips on this little paperweight.