docs

docs/analog.md

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+Analog Inputs
+=============
+_NB: this refers to general purpose analog inputs for things like CLT, TPS, MAP, etc.  High-speed inputs like triggers and knock have their own pages at [trigger](docs/design/trigger.md) and [knock](docs/design/knock.md)_
+
+## What do the analog inputs support? ##
+- 16 channels
+- 0-5v input
+- No input protection, other than 1k series resistor
+
+## How do the analog inputs work? ##
+- 16 channels are managed by 4 MCP6004 quad op-amps.
+- 1k + 1nf RC filter input to opamp non-inverting input.  This gives approximately 160khz of bandwidth.  If a lower knee is desired, additional circuitry can be added (series resistor, or another RC, etc) to the vehicle adapter.
+- Dual 1.5k resistor divider on the output, scaling 0-5v input to 0-2.5v output.  The input impedance of the STM32's ADC is on the order of 6k, so the exact value chosen does not appreciably alter the response of the system.
+
+## What do the analog inputs NOT do? ##
+- Input protection: this is highly pin specific, and may not be wanted if the signal is coming from the vehicle adapter board.  Appropriate larger series resistor and TVS diodes recommended.

docs/knock.md

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+Knock Sensor Inputs
+===================

docs/outputs.md

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+Outputs (injector, low side, and push-pull)
+===========================================

docs/power.md

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+Power Supplies
+==============

docs/trigger.md

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+Trigger (Hall & VR) Inputs
+==========================