NotesRequirements
I/O
Inputs
| Name | Type | Purpose |
|---|---|---|
| SHUTDOWN_IN | Digital/Analog | Power to BSPD Circuit — EV 7.7 |
| Brakes_ANALOG | Analog | Analog Brake Signal — EV 7.7.2 |
| Motor_CURRENT_SENSE | Digital | Motor Current Signal (Active when > 5kW) — EV 7.7.2 |
Outputs
| Name | Type | Purpose |
|---|---|---|
| SHUTDOWN_OUT | Digital/Analog | Shutdown circuit output |
Input/Output Flow
Logic
Possibly include HVC digitizer onboard too for REV A.
BRAKES_ANALOG is T when the analog current is at an arbitrary threshold.
SHUTDOWN_OUT is F when the shutdown circuit is open. The output signal is T when the shutdown circuit is closed, and current can continue to flow.
| SHUTDOWN_IN | BRAKES_ANALOG | CURRENT SENSE | SHUTDOWN_OUT |
|---|---|---|---|
| T | T | T | F |
| T | T | F | T |
| T | F | T | T |
| T | F | F | T |
| F | T | T | F |
| F | T | F | F |
| F | F | T | F |
| F | F | F | F |
Circuit Design
The output can be defined as:
| SHUTDOWN_IN | BRAKES | CURRENT SENSE | ||
|---|---|---|---|---|
| T | T | T | F | F |
| T | T | F | T | T |
| T | F | T | T | T |
| T | F | F | T | T |
| F | T | T | F | F |
| F | T | F | T | F |
| F | F | T | T | F |
| F | F | F | F | F |
\usepackage{circuitikz}
\begin{document}
\begin{circuitikz}
\draw (0,0) node[nand port](brakeinv) {}
(brakeinv.in 1) node [anchor=east] {}
(2,-1) node[nand port] (nand1) {}
(0, -2) node[nand port] (motorinv) {}
(brakeinv.out) -| (nand1.in 1) 3rd gate
(nand1.in 2) -- (nand2.in 2|-nand1.in 2)
(nand3.in 2) -- (nand2.in 2|-nand3.in 2)
;\end{circuitikz}