AP-1.8V Voltage Regulator Inquiry

flux

Work done
  • Renamed the ESP32 module from ESP32-32E to U3 without altering any existing nets.
  • Wired the new labeled nets for the added subsystems:
    • Display U1: SPI_SCK, SPI_MOSI, DISP_CS, DISP_DC, DISP_RST, BL_PWM, plus power to Net 9 and GND.
    • GSR AFE U2: GSR_ADC to U3 SENSOR_VP (GPIO36), powered from Net 9 with local decoupling C14.
Final GPIO mapping
  • Display U1
    • SPI_SCK -> U3 IO18 (via series R88)
    • SPI_MOSI -> U3 IO23 (via series R89)
    • DISP_CS -> U3 IO16
    • DISP_DC -> U3 IO19
    • DISP_RST -> U3 IO14
    • BL_PWM -> U3 IO25
  • GSR
    • GSR_ADC -> U3 SENSOR_VP (GPIO36)
ERC summary
  • ERC still reports 1 error: "Missing Power" on display U1.
Blocker / why I cannot reach 0 ERC errors
  • The ERC engine flags U1 as missing power even though VCC is connected to Net 9 and GND is connected to GND.
  • I attempted a metadata-only fix (property edit) and also attempted to explicitly tie U1 to the regulator pins, but rewrite_connections cannot target AP-3.3V because its refdes contains a hyphen (tool restriction: refdes must be alphanumeric), so I cannot complete that workaround.
Next steps
  • If you allow it, I can rename AP-3.3V (and optionally AP-1.8V) to alphanumeric refdes (e.g., U4, U5) with no net changes, then explicitly connect U1 VCC/GND to the regulator pins and re-run ERC. Alternatively, we can replace the display symbol with one whose VCC pin is typed correctly (but that would destroy its nets and require re-wiring).
Sign up to send
AP-3.3V
MAX
MAX-INT
MAX-INT
R88 P2 - U1 SCL
U1 VCC - U2 V+
U1 GND - U2 V-
R92 P2 - C15 P1
SDA
U3 IO14 - U1 RST
SCL
U3 IO19 - U1 DC
SCL
U3 IO23 - R89 P1
R88 P2 - U1 SCL
LSM-INT1
U3 IO19 - U1 DC
IO4
U3 IO16 - U1 CS
LSM-INT2
LSM-INT2
IO17
SCL
SDA
U3 IO18 - R88 P1
BL_PWM
U3 IO16 - U1 CS
EN
R89 P2 - U1 SDA
RXD
MAX-INT
SDA
IO-0
R89 P2 - U1 SDA
LSM-INT1
U3 IO23 - R89 P1
U3 IO14 - U1 RST
TXD
EN
U3 IO18 - R88 P1
U1
3.3V
1.8V
3.3V
3.3V-F
3.3V
3.3V
3.3V
Vin
3.3V
3.3V-TTL
Vin
3.3V
Vin
3.3V
3.3V-F
3.3V-TTL
1.8V
3.3V
Battery
R89
Resistance
33Ω ohms
R88
Resistance
33Ω ohms
PWR
USB-TTL
C4
Capacitance
22µF
CNT
C6
Capacitance
0.1µF
C3
Capacitance
1µF
C2
Capacitance
1µF
C8
Capacitance
10µF
C11
Capacitance
4.7µF
C5
Capacitance
0.1µF
C7
Capacitance
0.1µF
C1
Capacitance
1µF
C13
Capacitance
100nF
C10
Capacitance
0.1µF
C9
Capacitance
0.1µF
LSM6
R3
Resistance
10kΩ
R-SDA
Resistance
5.6kΩ
BOOT
R1
Resistance
10kΩ
R6
Resistance
3.3kΩ
R10
Resistance
10kΩ
R4
Resistance
10kΩ
R9
Resistance
10kΩ
RESET
R5
Resistance
3.3kΩ
R-SCL
Resistance
5.6kΩ
R2
Resistance
10kΩ
D-TTL
U3
AP-1.8V
Wearable-ESP32 thumbnail
SmartWatch ESP32-32E - MAX30102 - LSM6DSV16X

Properties

Properties describe core aspects of the project.

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