Linear voltage regulator IC identification circa 1988

[NrdyEE@home]

Hello all,
I have exhausted my search efforts and need assistance identifying the IC in the attached photo so I can obtain a datasheet and attempt to source a drop-in replacement. Here is what I know Based on the application use and by circuit inspection:
1. 5V linear regulator with 12v input
2. 5-pin in TO-220 package
3. PCA mfg date is 1988
The marking on the device is:
“57533
N DA
8739M”

Thanks

 

[Calm down]

I suggest you draw the surrounding components connected to his feet so that others can provide replacement models.If you can't find it, you can try connecting 7805 directly with wires as a substitute.See if this is it。

 

[dick_freebird]

If there's no close-in feedback components then likely 78xx: if a couple of resistors around the legs then maybe LM317 type gray market (no vendor logo = most suspicious).

But can't rule out other possibilities like this being a pass NPN at the tail of a zener ref stack and not an IC at all.

Have you chased down the number that appears on the case (not the date code)?

 

[FvM]

LM317 is 3-pin TO-220. There are some other 5-pin ICs that could be considered like ST (SGS) L200. But without tracing pin connections and possible related components, it's impossible to decide. Marking 57533 may be simply an OEM code.

 

[danadakk]

Possibly this series, 3.3V version. But they dont show a power package.

HT7533 datasheet(1/10 Pages) HOLTEK

HT75XXHigh Driver RegulatorSelection TablePart No.Output VoltageToleranceHT75303.0V±5%HT7533 Datasheet search, datasheets, Datasheet search site for Electronic Components and Semiconductors, integrated circuits, diodes, triacs and other semiconductors.

www.alldatasheet.com

Regards, Dana.