{"product_id":"giddings-lewis-cmos-memory-board-501-04090-00-502-03274-00-0226-721","title":"Giddings \u0026 Lewis CMOS Memory Board 501-04090-00 \/ 502-03274-00","description":"\u003cp\u003eUsed in Giddings \u0026amp; Lewis CNC control systems, the 501-04090-00 CMOS Memory Board is a full-size backplane-mounted circuit board identified by part number 501-04090-00 and assembly number 502-03274-00, with a manufacture date of 12\/83. The board label reads \"CMOS MEMORY BD.\" and is manufactured by Giddings \u0026amp; Lewis. The board features multiple rows of CMOS memory ICs across a large green PCB with gold-finger edge connectors on both sides. Battery backup is provided by three Panasonic BR-2\/3A 3V lithium cells along with a Gold Cap supercapacitor rated at 5.5V 0.33F, which together maintain CMOS memory contents during power-off conditions. Silkscreen designators indicate multiple memory banks labeled 0-16K, 16K-32K, 32K-48K, and 48K-64K, suggesting a total addressable capacity across those ranges. Board markings also reference part 302-70164-00 and 88164-00 on a small sub-assembly. A barcode label with internal tracking number 102000 is affixed to the lower left corner. This board is associated with the Giddings \u0026amp; Lewis Series 900 or similar CNC controller platforms that utilized large-format CMOS memory expansion boards. The secondary part number 502-03274-00 is also visible on the board label.\u003c\/p\u003e\n\n\u003cp\u003eStock # 0226-721\u003c\/p\u003e","brand":"Giddings \u0026 Lewis","offers":[{"title":"Default Title","offer_id":48916635975920,"sku":"m00721","price":1029.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0797\/6648\/7280\/files\/3884CD7E-8718-4DC4-A72B-AB39920CA3BB.jpg?v=1772116911","url":"https:\/\/mroexchange.com\/products\/giddings-lewis-cmos-memory-board-501-04090-00-502-03274-00-0226-721","provider":"MRO Exchange","version":"1.0","type":"link"}