A test structure (200) in an integrated circuit (100) includes a probe pad (210) disposed at a surface of a die (102) of the integrated circuit, a transmission gate (202) for connecting portions of an electronic circuit within the integrated circuit in response to a momentary signal applied to the probe pad, a first inverter (221) having an input coupled to the probe pad and having an output coupled to a control input of the transmission gate, and a second inverter (222) having an input coupled to an output of the first inverter and having an output coupled to another control input of the transmission gate. The output of the second inverter is coupled to the input of the first inverter. Upon power-up, the transmission gate is open. After the momentary signal is applied to the probe pad, the transmission gate closes and remains closed until power is disconnected.