A20B-3900-0042 Fanuc Module DRAM 4MB/2MB 4M/2M

Fanuc Memory board type DRAM Module reference FANUC A20B-3900-0042 for sale. DRAM Module 4M for Fanuc 16i, 18i, 20i and Fanuc 21i model. Fanuc DIMM memory module capacity of 4MB ready to install on your CNC Fanuc i series master board.. This Fanuc i series DIMM Module A20B-3900-0042 comes with a warranty.

CAUTION: Before starting the replacement of your PCB A20B-3900-0042, take a back up copy of the contents (parameters, programs, etc...) of your SRAM memory of the Fanuc CNC. The back up copy can be used in case the contents of the SRAM memory are lost during the replacement.

Dynamic random access memory (DRAM) is a type of random access memory that stores each bit of data in a separate capacitor within an integrated circuit. Since real capacitors leak charge, the information eventually fades unless the capacitor charge is refreshed periodically. Because of this refresh requirement, it is a dynamic memory as opposed to SRAM and other static memory. A20B-3900-0042