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README.md

+# Coil matrix MOSFET driver PCBs
+This repository contains the Kicad design files for a isolated DCDC
+converter module to drive N-channel MOSFETs and a control PCB to control
+up to 7 coils using GPIOs.
+
+## Control PCB
+The control PCB is designed to work with the matrix like MOSFET box. It is
+inteded to switch power supplies to coils as needed. Each PCB can control
+2 power supplies which are connected to 7 coils each.
+
+The seven coils outputs are isolated from the control logic, each one
+needs an independent, floating, power supply to drive it.
+
+The control input connectors are designed to match the Adafruit GPIO
+Expander Bonnet, but they can also be connected to anything else (single
+5V control pin per MOSFET).
+
+## Power supply PCB
+The power supply PCB uses a DCDC converter module from Recom to convert 5V
+to isolated +15V. The output is filtered to reduce the switching noise,
+this also loweres the output voltage to approx. 13.5V. The output is
+floating and can be used to drive N-channel MOSFETs on the high-side of
+the coils.