0.6mΩ high

Infineon Technologies has launched an ultra-low resistance high-side switch in a 9.9 x 11.7 x 2.3mm surface-mount package.

For automotive use on 12V circuits, the IC is “ISO 26262-ready for supporting the integrator in evaluation of hardware element according to ISO 26262:2018 Clause 8-13”, said the company.

Called BTS50005-1LUA, its nominal on-resistance is 0.6mΩ (1.1mΩ max at 150°C) and carrying up to 57A (85°C ambinet). BTS50010-1LUA, an almost identical device, is rated at 1.0mΩ and 42A.

“They are designed to control high-current applications, especially in hot cabin and engine compartment environments for demanding high inrush currents, such as in heaters, pumps and fans,” said the company, claiming: “They provide more than 1,000,000 switching cycles compared to, for example, in average 200,000 switching cycles of a relay,” and adding: “This family will be soon expanded with devices for 24V and 48V power nets.”

In the 0.6mΩ IC, minimum short circuit current threshold is 150A and operation is over 5.8 to 18V, or across 3.1 to 28V with some deviation from data sheet specs. Peaks are tolerated to +43V for load-dump protection and -18V for reversed battery faults. Maximum stand-by is a creditable 3µA (25°C).

Built-in protections include short-circuit, over-current, over-temperature and inductive load spike clamping, and a by asserting the ‘DEN’ pad (left) the host microcontroller has access to fault diagnostic information via the ‘IS’ pad, which doubles as a load current sense output via a ~50,000:1 divider – an optional two-point calibration can be used to improve sensing accuracy here.

For design, Infineon’s ‘Smart power switches intrinsic fuse tool’ and ‘Smart power switches kILIS tool’ are applicable – the intrinsic fuse tool calculates fusing characteristic based on the embedded over-temperature protection given certain boundary conditions, and the ‘kILIS’ tool calculates and displays the range of sense current for specific load current taking varying current sense ratio (dkILIS is Infineon’s name for the ratio parameter – ~50,000 in this case), sense resistor and ADC tolerance into account.

Evaluation hardware comes in the form of an Arduino Shield called, ‘BOARD BTS50005-1LUA’ (right).

The BTS50005-1LUA product page can be found here