Schematic Design Issue Review

flux

3:12

Project
BOM
Review (ERC/DRC)
Schematic
Accessed Knowledge (1)

Analyzing circuit components.

Reviewing circuit connections.

Assessing pull-up resistor needs.

Checking interrupt and power connections.

Evaluating net connections and components.

Checking pin connections and net names.

Using Review (ERC/DRC) Tool.

Using Schematic Tool.

Using BOM Tool.

Using Knowledge Base Tool.

Planning tool calls for schematic review.

Here is a focused, schematic-level review of your current design. I’m only calling out what is directly observable in the schematic and BOM.
Electrical and logical issues
  • Power pin connectivity
    • U2 VCC is on VBAT; U1 VS and VDD_IO are on VBAT; all GND pins of U1 and U2 are tied to GND. No ERC “Missing Power” errors reported.
  • SPI wiring
    • MOSI/MISO/SCLK/#CS are point-to-point between U1 and U2 on nets Net 7/Net 6/Net 16/Net 15 respectively. No pin-type conflicts reported.
  • SWD wiring
    • U2 SWDIO and SWCLK go through series resistors R1 and R3 to J2 pins 2 and 4. GND at J2 pins 3/5/9 and VBAT at pin 1 are present.
  • Reset net
    • U2 P0.21/~RESET is connected to J2 pin 10 and to C1 to GND (Net 14). There is no external pull-up/down resistor visible on this net.
  • Button input
    • SW1 pin 1 -> U2 P0.17 (Net 10), SW1 pin 3 -> GND; C6 from the button node to GND. No external pull-up/down resistor is present on this input.
  • Unused/legacy net portals
    • Multiple Net Portal components (e.g., named for SPI, reset, crystal, button) are placed but not actually connected to the functional nets. The active nets carry generic names (Net 7/Net 6/Net 16/Net 15/Net 14/Net 10/etc.). This is confusing and risks accidental miswires later.
Component-level review
  • Decoupling and bulk caps
    • VBAT has multiple 0.1 uF decouplers C3/C4/C5 to GND and bulk caps C2/C9 = 47 uF each on VBAT to GND. Presence is good.
    • Crystal load network for Y1 is implemented: C7 and C8 to GND; U2 P0.00/XTAL1 to Y1:2 (Net 9), P0.01/XTAL2 to Y1:1 (Net 11).
  • LED current limiting
    • LED1 anode is fed via R2 to VBAT (Net 17/VBAT). Cathode returns to U2 P0.18 (Net 3). Current-limiting resistor is present. BOM shows R2 = 2.2 kΩ.
  • SWD series damping
    • R1 and R3 are 33 Ω each in series with SWDIO/SWCLK. Presence confirmed in BOM.
  • Battery input
    • J1 POS connects to VBAT; NEG to GND. No reverse-polarity or input transient protection components are present on VBAT.
Power and signal integrity
  • Power distribution
    • Single rail VBAT powers U2 and U1. Bypass caps and bulk caps are present on VBAT. No intermediate regulation stage is present.
  • Signal integrity
    • Series resistors are only on SWD lines. SPI lines (Net 6/7/16/15) have no series terminations in the schematic; nothing inherently wrong is visible here at schematic level.
Schematic best practices and net labeling
  • Generic net names on critical signals
    • SPI and other key nets use generic names: Net 7 (MOSI), Net 6 (MISO), Net 16 (SCLK), Net 15 (ACC_CS), Net 8 (ACC_INT1), Net 2 (ACC_INT2), Net 10 (BUTTON), Net 3 (LED), Net 14 (RESET). Rename these nets to their functional names so they are self-documenting and recognized clearly by ERC.
  • Unused legacy portals
    • Remove or connect the stray Net Portal components intended for SPI/RESET/XTAL/BUTTON so the net names match the intended signal names. Keeping unconnected portals increases the chance of mistakes.
  • Power net metadata
    • Add a voltage property to VBAT and mark it as a Power net type. Clear power net naming and properties improve ERC/DRC behavior and readability.
Actionable corrections and optimizations
  • Reset net
    • Observation: No external pull resistor is present on U2 P0.21/~RESET (only C1 to GND). Action: If the device requires an external pull, add a pull-up per the module’s datasheet. If the capacitor is not recommended, remove/adjust per guidance.
  • Button input
    • Observation: No external pull-up/down on U2 P0.17 (button net). Action: If you are not relying on the MCU’s internal pull, add the appropriate pull resistor.
  • Net labeling cleanup
    • Rename the following nets:
      • Net 7 -> MOSI
      • Net 6 -> MISO
      • Net 16 -> SCLK
      • Net 15 -> ACC_CS
      • Net 8 -> ACC_INT1
      • Net 2 -> ACC_INT2
      • Net 10 -> BUTTON
      • Net 3 -> LED
      • Net 14 -> RESET
    • Delete or properly connect the currently unconnected Net Portal components for these signals.
  • Power net properties
    • Set VBAT as a Power net and add its voltage value in net properties.
  • Battery input robustness (optional improvement)
    • If needed for your use case, consider adding reverse-polarity protection and/or input surge/ESD protection on VBAT ahead of the rail that feeds U2/U1.
What I verified via project data
  • ERC summary: No schematic-level ERC errors reported (Missing Power, Pin-to-Pin conflicts, Single pin nets, Undriven nets all clear).
  • Crystal network is correctly cross-connected with its two load capacitors to GND.
  • LED has a series resistor; SWD lines have series resistors; decoupling and bulk capacitors exist on VBAT.
  • Several disconnected Net Portals exist while the live nets remain generically named.
If you want, I can:
  • Rename the nets listed above and remove the stray Net Portal instances.
  • Add pull resistors on RESET and the BUTTON input if you confirm they’re needed.
23 days

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SW1
LED1
C3
Capacitance
0.1uF
XTAL2
XTAL1
C6
Capacitance
0.1uF
J1
RESET
C7
Capacitance
12pF
Temperature Coefficient
C0G, NP0
VBAT
VBAT
C2
Capacitance
47uF
LED
BUTTON
C8
Capacitance
12pF
Temperature Coefficient
C0G, NP0
C9
Capacitance
47uF
X1
SCLK
R2
Resistance
2.2kΩ
VBAT
LED
BUTTON
R4
Resistance
100kΩ
U2
C1
Capacitance
0.1uF
  • Ground
    Ground
    A common return path for electric current. Commonly known as ground.
    jharwinbarrozo
    20.5M
  • Net Portal
    Net Portal
    Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
    jharwinbarrozo
    43.0M
  • Power Net Portal
    Power Net Portal
    Wirelessly connects power nets on schematic. Identical to the net portal, but with a power symbol. Used to organize schematics and separate functional blocks. To wirelessly connect power net portals, give them the same designator. #portal #power
    jharwinbarrozo
    11.4M
  • Generic Resistor
    Generic Resistor
    A generic fixed resistor for rapid developing circuit topology. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0Ω 10Ω 100Ω 1.0kΩ 10kΩ 100kΩ 1.0MΩ 1.1Ω 11Ω 110Ω 1.1kΩ 11kΩ 110kΩ 1.1MΩ 1.2Ω 12Ω 120Ω 1.2kΩ 12kΩ 120kΩ 1.2MΩ 1.3Ω 13Ω 130Ω 1.3kΩ 13kΩ 130kΩ 1.3MΩ 1.5Ω 15Ω 150Ω 1.5kΩ 15kΩ 150kΩ 1.5MΩ 1.6Ω 16Ω 160Ω 1.6kΩ 16kΩ 160kΩ 1.6MΩ 1.8Ω 18Ω 180Ω 1.8KΩ 18kΩ 180kΩ 1.8MΩ 2.0Ω 20Ω 200Ω 2.0kΩ 20kΩ 200kΩ 2.0MΩ 2.2Ω 22Ω 220Ω 2.2kΩ 22kΩ 220kΩ 2.2MΩ 2.4Ω 24Ω 240Ω 2.4kΩ 24kΩ 240kΩ 2.4MΩ 2.7Ω 27Ω 270Ω 2.7kΩ 27kΩ 270kΩ 2.7MΩ 3.0Ω 30Ω 300Ω 3.0KΩ 30KΩ 300KΩ 3.0MΩ 3.3Ω 33Ω 330Ω 3.3kΩ 33kΩ 330kΩ 3.3MΩ 3.6Ω 36Ω 360Ω 3.6kΩ 36kΩ 360kΩ 3.6MΩ 3.9Ω 39Ω 390Ω 3.9kΩ 39kΩ 390kΩ 3.9MΩ 4.3Ω 43Ω 430Ω 4.3kΩ 43KΩ 430KΩ 4.3MΩ 4.7Ω 47Ω 470Ω 4.7kΩ 47kΩ 470kΩ 4.7MΩ 5.1Ω 51Ω 510Ω 5.1kΩ 51kΩ 510kΩ 5.1MΩ 5.6Ω 56Ω 560Ω 5.6kΩ 56kΩ 560kΩ 5.6MΩ 6.2Ω 62Ω 620Ω 6.2kΩ 62KΩ 620KΩ 6.2MΩ 6.8Ω 68Ω 680Ω 6.8kΩ 68kΩ 680kΩ 6.8MΩ 7.5Ω 75Ω 750Ω 7.5kΩ 75kΩ 750kΩ 7.5MΩ 8.2Ω 82Ω 820Ω 8.2kΩ 82kΩ 820kΩ 8.2MΩ 9.1Ω 91Ω 910Ω 9.1kΩ 91kΩ 910kΩ 9.1MΩ #generics #CommonPartsLibrary
    jharwinbarrozo
    1.5M
  • Generic Capacitor
    Generic Capacitor
    A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF 10pF 100pF 1000pF 0.01uF 0.1uF 1.0uF 10uF 100uF 1000uF 10,000uF 1.1pF 11pF 110pF 1100pF 1.2pF 12pF 120pF 1200pF 1.3pF 13pF 130pF 1300pF 1.5pF 15pF 150pF 1500pF 0.015uF 0.15uF 1.5uF 15uF 150uF 1500uF 1.6pF 16pF 160pF 1600pF 1.8pF 18pF 180pF 1800pF 2.0pF 20pF 200pF 2000pF 2.2pF 22pF 20pF 2200pF 0.022uF 0.22uF 2.2uF 22uF 220uF 2200uF 2.4pF 24pF 240pF 2400pF 2.7pF 27pF 270pF 2700pF 3.0pF 30pF 300pF 3000pF 3.3pF 33pF 330pF 3300pF 0.033uF 0.33uF 3.3uF 33uF 330uF 3300uF 3.6pF 36pF 360pF 3600pF 3.9pF 39pF 390pF 3900pF 4.3pF 43pF 430pF 4300pF 4.7pF 47pF 470pF 4700pF 0.047uF 0.47uF 4.7uF 47uF 470uF 4700uF 5.1pF 51pF 510pF 5100pF 5.6pF 56pF 560pF 5600pF 6.2pF 62pF 620pF 6200pF 6.8pF 68pF 680pF 6800pF 0.068uF 0.68uF 6.8uF 68uF 680uF 6800uF 7.5pF 75pF 750pF 7500pF 8.2pF 82pF 820pF 8200pF 9.1pF 91pF 910pF 9100pF #generics #CommonPartsLibrary
    jharwinbarrozo
    1.5M
  • Generic Inductor
    Generic Inductor
    A generic fixed inductor for rapid developing circuit topology. *You can now change the footprint and 3D model at the top level anytime you want. This is the power of #generics
    jharwinbarrozo
    15.5k
  • Terminal
    Terminal
    An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
    natarius
  • RMCF0805JT47K0
    RMCF0805JT47K0
    47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film #forLedBlink
    jharwinbarrozo
    1.2M
  • 875105359001
    875105359001
    10uF Capacitor Aluminum Polymer 20% 16V SMD 5x5.3mm #forLedBlink #commonpartslibrary #capacitor #aluminumpolymer #radialcan
    jharwinbarrozo
    1.2M
  • CTL1206FYW1T
    CTL1206FYW1T
    Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric) #forLedBlink
    jharwinbarrozo
    1.1M
nrf52_tilt_sensor_flat_battery_Modules_approach2 thumbnail
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