The TLB file extension is related to the VAX and used for its text library files.
TLB file extension - VAX text library
What is tlb file? How to open tlb files?
File type specification:
The TLB file extension is also related to VAX, an instruction set architecture (ISA) developed by Digital Equipment Corporation (DEC) in the mid-1970s. A 32-bit complex instruction set computer (CISC) ISA, it was designed to extend or replace DEC's various Programmed Data Processor (PDP) ISAs. The VAX name was also used by DEC for a family of computer systems based on this processor architecture.