# Voltage-domain ERC — sim-pilot

0 error(s), 1 warning(s). Ambient 40 °C. Specs: `specs/parts/`.

## Findings

| sev | code | where | detail |
|---|---|---|---|
| WARN | CONN_LOAD_UNDECLARED | J4.2 | +3V3 from U2 leaves the board on J4.2 (Pin_2) with no declared load: U2 can supply 150 mA in total (rated 500 mA, thermal 150 mA: Tj 125 °C at 40 °C ambient, θJA 250 °C/W -> 340 mW; (5.50 - 3.23) V across it); this board uses 30 mA of it, so 120 mA are left for what is connected. Declare the current drawn there in erc.yaml connector_loads (J4.2: <mA>; 0 if nothing draws from it) and state the real available current |

## Rails (power budget)

| rail | source | V | load mA | rated mA | use | nets |
|---|---|---|---|---|---|---|
| +3V3 | U2 | 3.23..3.37 | 30.0 | 500 | 6 % | +3V3 |
| VBUS | external | 4.75..5.5 | 30.1 | - |  | VBUS, +5V |

### Loads

| rail | net | ref.pin | mA |
|---|---|---|---|
| +3V3 | +3V3 | U1.24 | 30.00 |
| VBUS | +5V | U2.in | 30.05 |

### Beads / series inductors

| ref | from | to | mA | DCR Ω | drop mV | rated mA |
|---|---|---|---|---|---|---|
| F1 | VBUS | +5V | 30.1 | 0.5 | 15.0 | 750 |

## Thermal budget

| ref | part | P mW | basis | θJA °C/W | Tj °C | limit °C | |
|---|---|---|---|---|---|---|---|
| U1 | STM32F411CEU6 | 101 | Σ V·I_max of supply pins | 32 | 43 | 105 | ok |
| U2 | RT9013-33GB | 68 | (5.50-3.23) V x 30 mA | 250 | 57 | 125 | ok |

## Power out through connectors

Regulator outputs that leave the board (declared in erc.yaml `connector_loads`; the regulator's total capacity is the lower of its rating and its thermal limit at the worst-case input and ambient).

| pin | rail | source | declared mA | rated mA | thermal mA | board's own mA | left mA | |
|---|---|---|---|---|---|---|---|---|
| J4.2 (Pin_2) | +3V3 | U2 | UNDECLARED | 500 | 150 | 30 | 120 | Tj 125 °C at 40 °C ambient, θJA 250 °C/W -> 340 mW; (5.50 - 3.23) V across it |

## Per-pin table

| ref | pin | name | type | net | V | limit | status |
|---|---|---|---|---|---|---|---|
| D1 | 1 | K | passive | GND | 0 |  | ok |
| D1 | 2 | A | passive | LED_PWR_A | 3.23..3.37 |  | ok |
| D2 | 1 | K | passive | GND | 0 |  | ok |
| D2 | 2 | A | passive | LED_STAT_A | 0..3.37 |  | ok |
| F1 | 1 | 1 | passive | VBUS | 4.75..5.5 |  | ok |
| F1 | 2 | 2 | passive | +5V | 4.73..5.5 |  | ok |
| J1 | A1 | GND | passive | GND | 0 |  | ok |
| J1 | A4 | VBUS | passive | VBUS | 4.75..5.5 |  | ok |
| J1 | A5 | CC1 | passive | CC1 | 0 |  | ok |
| J1 | A6 | DP1 | passive | - | ? |  | nc |
| J1 | A7 | DN1 | passive | - | ? |  | nc |
| J1 | A8 | SBU1 | passive | - | ? |  | nc |
| J1 | A9 | VBUS | passive | VBUS | 4.75..5.5 |  | ok |
| J1 | A12 | GND | passive | GND | 0 |  | ok |
| J1 | B1 | GND | passive | GND | 0 |  | ok |
| J1 | B4 | VBUS | passive | VBUS | 4.75..5.5 |  | ok |
| J1 | B5 | CC2 | passive | CC2 | 0 |  | ok |
| J1 | B6 | DP2 | passive | - | ? |  | nc |
| J1 | B7 | DN2 | passive | - | ? |  | nc |
| J1 | B8 | SBU2 | passive | - | ? |  | nc |
| J1 | B9 | VBUS | passive | VBUS | 4.75..5.5 |  | ok |
| J1 | B12 | GND | passive | GND | 0 |  | ok |
| J1 | SH | SHIELD | passive | GND | 0 |  | ok |
| J2 | 1 | Pin_1 | passive | GND | 0 |  | ok |
| J2 | 2 | Pin_2 | passive | UART_TX | 0..3.37 |  | ok |
| J2 | 3 | Pin_3 | passive | UART_RX | 0..3.37 |  | ok |
| J3 | 1 | Pin_1 | passive | SWDIO | 0..3.37 |  | ok |
| J3 | 2 | Pin_2 | passive | SWCLK | 0..3.37 |  | ok |
| J3 | 3 | Pin_3 | passive | NRST | 0..3.37 |  | ok |
| J3 | 4 | Pin_4 | passive | GND | 0 |  | ok |
| J4 | 1 | Pin_1 | passive | GND | 0 |  | ok |
| J4 | 2 | Pin_2 | passive | +3V3 | 3.23..3.37 |  | ok |
| J4 | 3 | Pin_3 | passive | GPS_TX | 0..3.37 |  | ok |
| J4 | 4 | Pin_4 | passive | GPS_RX | 0..3.37 |  | ok |
| J5 | 1 | Pin_1 | passive | GND | 0 |  | ok |
| J5 | 2 | Pin_2 | passive | +5V | 4.73..5.5 |  | ok |
| J5 | 3 | Pin_3 | passive | PWM1 | 0..3.37 |  | ok |
| J6 | 1 | Pin_1 | passive | GND | 0 |  | ok |
| J6 | 2 | Pin_2 | passive | +5V | 4.73..5.5 |  | ok |
| J6 | 3 | Pin_3 | passive | PWM2 | 0..3.37 |  | ok |
| J7 | 1 | Pin_1 | passive | GND | 0 |  | ok |
| J7 | 2 | Pin_2 | passive | +5V | 4.73..5.5 |  | ok |
| J7 | 3 | Pin_3 | passive | PWM3 | 0..3.37 |  | ok |
| J8 | 1 | Pin_1 | passive | GND | 0 |  | ok |
| J8 | 2 | Pin_2 | passive | +5V | 4.73..5.5 |  | ok |
| J8 | 3 | Pin_3 | passive | PWM4 | 0..3.37 |  | ok |
| SW1 | 1 | 1 | passive | BTN | 0..3.37 |  | ok |
| SW1 | 2 | 2 | passive | GND | 0 |  | ok |
| U1 | 1 | VBAT | supply | +3V3 | 3.23..3.37 | min 1.7 max 3.6 abs 4 | ok |
| U1 | 2 | PC13-ANTI_TAMP | io | - | ? |  | nc |
| U1 | 3 | PC14-OSC32_IN | io | - | ? |  | nc |
| U1 | 4 | PC15-OSC32_OUT | io | - | ? |  | nc |
| U1 | 5 | PH0-OSC_IN | io | - | ? |  | nc |
| U1 | 6 | PH1-OSC_OUT | io | - | ? |  | nc |
| U1 | 7 | NRST | io | NRST | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 8 | VSSA | ground | GND | 0 |  | ok |
| U1 | 9 | VREF+ | supply | +3V3 | 3.23..3.37 | min 1.7 max 3.6 abs 4 | ok |
| U1 | 10 | PA0-WKUP | io | BTN | 0..3.37 | max 3.53 abs 4 | ok |
| U1 | 11 | PA1 | io | - | ? |  | nc |
| U1 | 12 | PA2 | io | UART_TX | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 13 | PA3 | io | UART_RX | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 14 | PA4 | io | - | ? |  | nc |
| U1 | 15 | PA5 | io | LED_STAT | 0..3.37 | max 3.53 abs 4 | ok |
| U1 | 16 | PA6 | io | PWM1 | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 17 | PA7 | io | PWM2 | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 18 | PB0 | io | PWM3 | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 19 | PB1 | io | PWM4 | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 20 | PB2 | io | - | ? |  | nc |
| U1 | 21 | PB10 | io | - | ? |  | nc |
| U1 | 22 | VCAP1 | passive | VCAP1 | ? |  | ok |
| U1 | 23 | VSS | ground | GND | 0 |  | ok |
| U1 | 24 | VDD | supply | +3V3 | 3.23..3.37 | min 1.7 max 3.6 abs 4 | ok |
| U1 | 25 | PB12 | io | - | ? |  | nc |
| U1 | 26 | PB13 | io | - | ? |  | nc |
| U1 | 27 | PB14 | io | - | ? |  | nc |
| U1 | 28 | PB15 | io | - | ? |  | nc |
| U1 | 29 | PA8 | io | - | ? |  | nc |
| U1 | 30 | PA9 | io | GPS_RX | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 31 | PA10 | io | GPS_TX | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 32 | PA11 | io | - | ? |  | nc |
| U1 | 33 | PA12 | io | - | ? |  | nc |
| U1 | 34 | PA13 | io | SWDIO | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 35 | VSS | ground | GND | 0 |  | ok |
| U1 | 36 | VDD | supply | +3V3 | 3.23..3.37 | min 1.7 max 3.6 abs 4 | ok |
| U1 | 37 | PA14 | io | SWCLK | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 38 | PA15 | io | - | ? |  | nc |
| U1 | 39 | PB3 | io | - | ? |  | nc |
| U1 | 40 | PB4 | io | - | ? |  | nc |
| U1 | 41 | PB5 | io | - | ? |  | nc |
| U1 | 42 | PB6 | io | I2C_SCL | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 43 | PB7 | io | I2C_SDA | 0..3.37 | max 5.5 abs 7.23 | ok |
| U1 | 44 | BOOT0 | input | BOOT0 | 0 | max 9 abs 9 | ok |
| U1 | 45 | PB8 | io | - | ? |  | nc |
| U1 | 46 | PB9 | io | - | ? |  | nc |
| U1 | 47 | VSS | ground | GND | 0 |  | ok |
| U1 | 48 | VDD | supply | +3V3 | 3.23..3.37 | min 1.7 max 3.6 abs 4 | ok |
| U1 | 49 | EP | ground | GND | 0 |  | ok |
| U2 | 1 | VIN | supply | +5V | 4.73..5.5 | min 2.2 max 5.5 abs 6 | ok |
| U2 | 2 | GND | ground | GND | 0 |  | ok |
| U2 | 3 | EN | input | +5V | 4.73..5.5 | min 0 max 5.5 abs 6 | ok |
| U2 | 4 | NC | nc | - | ? |  | nc |
| U2 | 5 | VOUT | supply_out | +3V3 | 3.23..3.37 |  | ok |
| U3 | 1 | SDO/SA0 | io | GND | 0 |  | ok |
| U3 | 2 | SDx | input | GND | 0 |  | ok |
| U3 | 3 | SCx | input | GND | 0 |  | ok |
| U3 | 4 | INT1 | output | - | ? |  | nc |
| U3 | 5 | VDDIO | supply | +3V3 | 3.23..3.37 | min 1.62 max 3.6 abs 4.8 | ok |
| U3 | 6 | GND | ground | GND | 0 |  | ok |
| U3 | 7 | GND | ground | GND | 0 |  | ok |
| U3 | 8 | VDD | supply | +3V3 | 3.23..3.37 | min 1.71 max 3.6 abs 4.8 | ok |
| U3 | 9 | INT2 | output | - | ? |  | nc |
| U3 | 10 | OCS_Aux | nc | - | ? |  | nc |
| U3 | 11 | SDO_Aux | nc | - | ? |  | nc |
| U3 | 12 | CS | input | +3V3 | 3.23..3.37 |  | ok |
| U3 | 13 | SCL | input | I2C_SCL | 0..3.37 |  | ok |
| U3 | 14 | SDA | io | I2C_SDA | 0..3.37 |  | ok |

## Spec sources

- `examples/sim-pilot/specs/KT-0603G.yaml` (KT-0603G): research/KT-0603G.pdf (sha256 770831ccd4b3...), Hubei KENTO KT-0603G spec for approval rev A.0 (LCSC C12624): Absolute Maximum Ratings, Electrical Optical Characteristics
- `examples/sim-pilot/specs/nSMD075.yaml` (nSMD075): research/nSMD075.pdf (sha256 986063e150e6...), PTC resettable fuse nSMD series (LCSC C70078): electrical characteristics table (nSMD075 row), Ihold vs temperature table
- `examples/sim-pilot/specs/TYPE-C-31-M-12.yaml` (TYPE-C-31-M-12): research/TYPE-C-31-M-12.pdf (sha256 6ae33d50ac47...), Korean Hroparts TYPE-C-31-M-12 drawing (LCSC C165948); pin names follow the USB Type-C receptacle pinout
- `examples/sim-pilot/specs/PZ254V-11-03P.yaml` (PZ254V-11-03P): Generic 1x3 2.54 mm header; no electrical limits used by ERC
- `examples/sim-pilot/specs/PZ254V-11-04P.yaml` (PZ254V-11-04P): Generic 1x4 2.54 mm header; no electrical limits used by ERC
- `examples/sim-pilot/specs/TS-1187A-B-A-B.yaml` (TS-1187A-B-A-B): research/TS-1187A-B-A-B.pdf (sha256 64b75233cada...), XKB TS-1187A-X-X-X tactile switch (LCSC C318884): drawing, 5.1 x 5.1 mm SMD, 4 pads in two joined pairs
- `examples/sim-pilot/specs/STM32F411CEU6.yaml` (STM32F411CEU6): research/STM32F411CEU6.pdf (sha256 284b85ff62b0...), ST DS10314 (DocID026289) Rev 4, February 2015: STM32F411xC/xE datasheet
- `examples/sim-pilot/specs/RT9013-33.yaml` (RT9013-33GB): research/RT9013-33GB.pdf (sha256 779688f55e44...), Richtek DS9013-10 (Apr 2011, LCSC C47773): Functional Pin Description (SOT-23-5), Absolute Maximum Ratings, Recommended Operating Conditions, Electrical Characteristics
- `examples/sim-pilot/specs/LSM6DSOTR.yaml` (LSM6DSOTR): research/LSM6DSOTR.pdf (sha256 1074e3973959...), ST DS12140 Rev 2 (Jan 2019, LCSC C2655100): Table 1 Pin description, Table 3 Electrical characteristics, Table 7 Absolute maximum ratings, Section 6.1.1 I2C address, Section 7 Application hints