The TZC-400 TrustZone Address Space Controller (TZC-400) implements filters between ACE-Lite masters and ACE-Lite slaves to perform security checks on transactions to memory or peripherals using up to eight separate regions in the address space, each with an individual security level setting. Each filter unit operates in its own clock domain and has an AXI low-power interface for clock gating. Each domain can operate asynchronously from all other domains. It is used in a TrustZone system to implement the security requirements for the SoC.