Abstract: A secure device (1) has a circuit board (2) with various exposed components such as an LCD (4) and keys (40). A secure circuit (10) is housed within an enclosure formed between the board (2) and a cover (11). The cover (11) has, on its inside surface, a security track (23) in a dense serpentine pattern. The board (2) has a security track (52), also in a dense serpentine pattern, is an inner layer. The track (52) is linked to covered surface-level tracks (27) by vias (64). The cover's security track (23) is connected to the board's security tracks (52, 27) via a deformable pad (25) whose conductivity increases with applied compression.