{"id":"mk-us-sierra-circuits","name":"Sierra Circuits (ProtoExpress)","name_local":"unknown","entity_type":"factory","country":"US","region":"California","city":"Sunnyvale","address":"1108 West Evelyn Avenue, Sunnyvale, CA 94086, USA","website":"https://www.protoexpress.com/","processes":["pcb-fab","flex-pcb","pcba","electronics-design","testing-certification"],"processes_basis":"stated","specialty":"Factory: Silicon Valley quick-turn PCB fab and turnkey assembly with online instant quotes for standard and Turnkey PRO boards.","capabilities":"Turnkey PRO (fab + parts + assembly), standard rigid PCBs, advanced PCBs with dedicated CAM engineer, component sourcing, flying probe test, design support.","parts_made":["prototype PCBs","assembled boards"],"materials":"unknown","tolerance":"unknown","max_part_size":"unknown","certifications":["AS9100D","ISO 9001:2015","ISO 13485:2016","IPC-6012 Class 2/3","UL","MIL-PRF-31032","ITAR registered"],"volume":{"moq":"unknown","prototype_ok":"yes","low_volume_evidence":"\"Quick-turn Rigid PCB prototypes\" https://www.protoexpress.com/","startup_friendly":"unknown"},"lead_time":{"quote":"instant online (Turnkey PRO, Standard)","prototype":"standard PCBs 1-10 business days, 24-hour available; assembled as fast as 5 days","production":"advanced PCBs same day to 4 weeks"},"size":{"employees":"unknown","floor_area":"unknown","founded":"unknown","band":"unknown"},"english":"yes","instant_quote":"yes","known_customers":"unknown","platforms":[],"contact_public":{"email":"unknown","phone":"+1 (800) 763-7503","source":"https://www.protoexpress.com/"},"community":[],"doubt":"Directory already has 'Sierra Circuits Asia' (Guangzhou) — this is the separate US Sunnyvale entity; check for overlap.","sources":[{"url":"https://www.protoexpress.com/","what":"services, address, lead times, certifications, phone"}],"confidence":"VERIFIED","verification":"desk-research","as_of":"2026-10-30"}