Testable electronic circuit

Abstract

An electronic circuit contains groups of flip-flops (-), coupled to data terminals (-) of the circuit and to a functional circuit (). Each group (-) has a clock input for clocking the flip-flops of the group. Each group (-) can be switched between a shift configuration and a functional configuration, for serially shifting in test data from the data terminals and to function in parallel to supply signals to the functional circuit () and/or receive signals from the functional circuit () respectively. A test control circuit () can be switched between a functional mode, a test shift mode and a test normal mode. The test control circuit () is coupled to the groups of flip-flops (-) to switch the groups to the functional configuration in the functional mode and to the shift configuration in the test shift mode. A clock multiplexing circuit (-) has inputs coupled to the data terminals (-) and outputs coupled to clock inputs of the groups (-). The test control circuit () is coupled to control the clock multiplexing circuit (-) dependent on the mode assumed by the test control circuit (). The clock multiplexing circuit (-) is arranged to substitute clock signals from respective ones of the data terminals (-) temporarily at the clock inputs of respective ones of the groups (-) in the test normal mode.