Power surge threats such as lightning, power cross and power induction threaten systems everyday. Bourns Transient Blocking Unit (TBU) solutions offer the first new approach to circuit protection in over a decade. TBU’s block rather than shunt an electrical surge which virtually eliminates latency in the circuit protection design resulting in highly reliable protection within nanoseconds. This white paper provides an overview of different circuit protection technologies, how TBU devices work and details TBU performance through test results under varying surge conditions.