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Highside Driver Circuits

A high-side output switches the positive side of a load. When enabled, the driver connects the output to its supply; the load's return remains connected to ground. This differs from a low-side output, which switches the return path. Do not infer that a connector labelled as a high side can be grounded as if it were a low side.

An inductive load stores energy while current flows. When a high-side device turns off, the current needs a controlled recirculation path. The driver may contain an internal clamp, while another board may depend on an external freewheel diode or suppressor. Verify that path in the exact board schematic. Also verify the driver's permitted supply, continuous and peak current, PWM frequency, and diagnostics before selecting a load. Those are device and revision facts, not Capoworks settings.

In Capoworks, choose an output exposed by the installed board target and assign it to the required function. The board pin map names high-side, low-side, ignition, and generic outputs; the firmware does not create a high-side power stage from an MCU pin. Output-mode settings can invert the command or select an open-collector-style pin, but they do not change the external topology. Controllers publish a requested state or duty cycle, and the board output stages perform the switching.

For commissioning, confirm the chosen output and mode, command a safe no-load state, and check the corresponding output command and board supply path. If a small pilot device works but the intended inductive load does not, stop and inspect the clamp and driver rating rather than increasing duty. Repeated driver faults or unexpected turn-off spikes may indicate a missing or incorrect recirculation path. Grounds, connector pin numbers, and protection components must come from the matching revision documentation. The Atlas and Universal 112 pages describe only their documented boards.

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