Problem: Traditional Key-injection Complicates Inventory Management

Semiconductor manufacturers want to be responsive to swings in market demand. But legacy root key creation/storage methods, such as key injection and storage in OTP, require rigid, “early-in-life” personalization. This leads to problems such as complexity, longer lead time, and occasional inventory write-offs.

Drawback of Legacy Methods


  • Key management adds complexity and liabilities
  • Key storage mechanisms depend on chip technology process and fabrication plant which adds costs and time to market


OEM-specific keys make a rigid inventory build

  • Complex management
  • Potential for inventory write-offs
  • Higher Days Inventory Outstanding (DIO)

Benefits of SRAM PUF Approach


  • No need to handle keys, no supply chain liabilities
  • No additional hardware for secure key storage required



  • Common hardware inventory for all OEM customers
  • Secure, even in a non-trustworthy supply chain
  • Precision management of build inventory
  • Lower Days Inventory Outstanding (DIO)

Contract Manufacturer / OEM / In the field

Just-in-time key management: generation of unclonable device-unique keys from the SRAM PUF