From 78c4dd1998856a1dd2f454a5486f1868bfb2b825 Mon Sep 17 00:00:00 2001 From: Matthew Kennedy Date: Thu, 3 Jan 2019 17:08:38 -0800 Subject: [PATCH] docs --- docs/analog.md | 16 ++++++++++++++++ docs/knock.md | 2 ++ docs/outputs.md | 2 ++ docs/power.md | 2 ++ docs/trigger.md | 2 ++ 5 files changed, 24 insertions(+) create mode 100644 docs/analog.md create mode 100644 docs/knock.md create mode 100644 docs/outputs.md create mode 100644 docs/power.md create mode 100644 docs/trigger.md diff --git a/docs/analog.md b/docs/analog.md new file mode 100644 index 0000000..e127d6c --- /dev/null +++ b/docs/analog.md @@ -0,0 +1,16 @@ +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. diff --git a/docs/knock.md b/docs/knock.md new file mode 100644 index 0000000..176d75a --- /dev/null +++ b/docs/knock.md @@ -0,0 +1,2 @@ +Knock Sensor Inputs +=================== diff --git a/docs/outputs.md b/docs/outputs.md new file mode 100644 index 0000000..f1d861b --- /dev/null +++ b/docs/outputs.md @@ -0,0 +1,2 @@ +Outputs (injector, low side, and push-pull) +=========================================== diff --git a/docs/power.md b/docs/power.md new file mode 100644 index 0000000..ed9184b --- /dev/null +++ b/docs/power.md @@ -0,0 +1,2 @@ +Power Supplies +============== diff --git a/docs/trigger.md b/docs/trigger.md new file mode 100644 index 0000000..76f8177 --- /dev/null +++ b/docs/trigger.md @@ -0,0 +1,2 @@ +Trigger (Hall & VR) Inputs +==========================