Improved electrical transient blocking is provided with a transient blocking unit (TBU) having a partial disconnect capability. A TBU is an arrangement of voltage controlled switches that normally conducts, but switches to a disconnected state in response to an above-threshold input transient. Partial disconnection improves the power handling capability of a TBU by preventing thermal damage to the TBU. Partial TBU disconnection can be implemented to keep power dissipation in the TBU below a predetermined level P<SUB>max</SUB>, thereby avoiding thermal damage to the TBU by keeping the TBU temperature below a temperature limit T<SUB>max</SUB>. Alternatively, partial TBU disconnection can be implemented to keep TBU temperature below T<SUB>max</SUB> using direct temperature sensing and feedback.
