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Check that none of the unconnected pins require pull-up or pull-down resistors t...
2y
Given the description of the project, it seems no information about individual pin requirements for pull-ups or pull-downs was provided. However, for many components, general practices apply.
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I2C bus (SDA / SCL): The I2C pins, specifically SDA (Data line) and SCL (Clock line), typically need pull-up resistors since it's an open-drain bus. Your project seems to have some I2C communication because it includes both SDA and SCL nets. If you don't already have pull-up resistors connected to these lines on your schematic, I recommend connecting them.
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Enable (EN) pins: Normally, for digital ICs, if an Enable (EN) pin is not expected to be driven by another GPIO, it's a good practice to pull it either to ground (for active high enable) or to Vcc (for active low enable) to have defined behavior.
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Reset pins: Reset (RST) pins are typically active-low and are often pulled up to avoid accidental resets.
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Communication lines such as USB D+/D-: These lines normally come with their pull-up / pull-down circuitry on a connected device. So, if there's an external device connected on those lines, you probably won't require additional pull-up/downs. You just have to match the impedance for these lines.
Still, the decision strongly depends on each specific design requirements. You should check the datasheets of your components (mainly U1 and IC2) to verify the kind of connection each pin requires.
Please keep in mind, pull-up and pull-down resistors can take a variety of forms depending on the context, which might not always be obvious based on a generic schematic. It's also considered good practice to connect any un-used digital pins to a known state (either high, low, or via a pull-up or pull-down), rather than letting them float, as this can lead to an unpredictable behavior.
2y
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6
to connect LED1 correctly, what value should I choose for the R6?
2y
To suggest a suitable resistance for R6, we need to know the desired forward current (I_f) for LED1 (the LTST-C191KGKT). Unfortunately, I don't have a datasheet excerpt for the LED and can't provide that detail.
However, assuming typical values, most standard LEDs have forward voltage (V_f) around 2.0V to 2.2V and operate at around 20mA (0.020A) forward current.
Here is how to calculate the resistance:
The IC2 (TPS62130RGTR) regulator provides 3.3V, and the forward voltage of the LED would be around 2.0-2.2V. Using Ohm's law, resistance (R) is:
R = (Voltage of IC2 - Forward voltage of the LED)/desired forward current of the LED
Assuming the forward voltage V_f of the LED is 2.1V and the desired forward current I_f is 20mA, and the output voltage of IC2 is 3.3V,
R = (3.3V - 2.1V) / 0.020A = 60 ohms
You should pick the standard resistor value of 68 ohms for R6.
Please verify this with the actual forward voltage and forward current from the LED manufacturer's datasheet. And remember, LEDs should be connected in the correct polarity to prevent damage: connect the anode (A) of LED1 to the positive side (output of R6), and the cathode (K) to the negative side (GND).
2y
Datasheet URL is provided in the description you can find
2y
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2y
Datasheet URL is provided in the description you can find
2y
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2y
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11
12
R3
Resistance
5.1k Ω
GND
R10
Resistance
10k Ω
GND
LED
R6
Resistance
200 Ω
C6
Capacitance
100p F
SW1
3V3_USB
SCL
J1
SCD41_EN
R4
Resistance
5.1k Ω
C2
Capacitance
10u F
USB_D+
U1
3V3_EN
IC1
USB_D-
LED
C9
Capacitance
22u F
+5V
R11
Resistance
10k Ω
R7
Resistance
100k Ω
3V3_USB
3V3_EN
3V3_USB
3V3_USB
SDA
USB_D+
1V8_EN
SDA
SCL
SGP41_EN
USB_D-
SHT40_EN
C7
Capacitance
100p F
GND
LED1
L2
Inductance
2.2u H
R2
Resistance
100K Ω
D2
Capacitance
12p F
R12
Resistance
Resistance
R1
Resistance
Resistance
Reviews
Electrical Rule Checks
Missing Footprints
Reports parts that have no footprint.
Design Rule Checks
Overlapping Copper • 8
Invalid Layer
Reports nodes that are assigned to a layer that doesn't exist in the layout stackup.
Component Overrides
Reports components that have been modified using the "!important" flag.
Airwires • 59
Designators | Net | |
|---|---|---|
Deprecated Rules
Reports nodes that are using rules that are not supported anymore.
Layers with Multiple Fills
Reports layers that have multiple copper fills of different nets. Make sure the Connected Layers rule value of nets with fills is valid.
Floating Copper
Detect any via, trace or copper fill island that is not connected to any net.
Protected Intrusions
Reports intrusions from objects of other nets into polygons or fills that have the Protected layout rule applied.
System Checks
Auto-Layout
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Passive Components
Resistor Power Rating
BetaChecks that the power traveling across a given resistor is under its rating with 50% headroom.
Learn morePull Up/Pull Down Presence
BetaChecks that IC pins that require pull up or pull down resistors have them.
Learn moreCapacitor Voltage Rating
BetaChecks that capacitors have appropriate voltage ratings to prevent overheating and ensure reliable circuit operation.
- Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portaljharwinbarrozo43.0M
- 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 #powerjharwinbarrozo11.4M
- 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 #CommonPartsLibraryjharwinbarrozo1.5M
- 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 #CommonPartsLibraryjharwinbarrozo1.5M
- 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 #genericsjharwinbarrozo15.1k
- An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.Terminal
- 47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film #forLedBlinkjharwinbarrozo1.2M
- 10uF Capacitor Aluminum Polymer 20% 16V SMD 5x5.3mm #forLedBlink #commonpartslibrary #capacitor #aluminumpolymer #radialcanjharwinbarrozo1.2M
- Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric) #forLedBlinkjharwinbarrozo1.1M
Inspect
WLR
Controls
Properties
Availability & Pricing
| Distributor | Qty 1 | |
|---|---|---|
| Digi-Key | $18.68–$20.29 | |
| LCSC | $1.32 | |
| Mouser | $19.32 | |
Assets
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okanaraz
copilot
SCD41_ENconnected to theU1:PA221V8_ENconnected to theU1:PA27~RESET~ofU13V3_ENconnected to theU1:PA28ENof theIC2SCD41_EN: This line doesn't appear to be connected to any resistors, so no pull-up or pull-down resistor appears to be present.1V8_EN: This line doesn't appear to be connected to any resistors, implying there is no pull-up or pull-down resistor associated.~RESET~: Reset line is connected through the resistorR7. We can't determine if it's a pull-up or pull-down resistor without knowing the other components connected to the~RESET~line or the circuit's Vcc.3V3_EN: This line isn't connected to any resistors, suggesting there's no pull-up or pull-down resistor involved.ENofIC2: This pin seems to be connected directly to the+5Vpower supply without a resistor, meaning there isn't a pull-up or pull-down resistor for this signal.SCD41_ENnet.1V8_ENnet.~RESET~configuration to confirm whetherR7is used as a pull-up or pull-down resistor. If not, add one as needed.3V3_ENnet.ENpin ofIC2is directly connected to power, which means it's always enabled. If adjustable enabling is required, consider adding a transistor switch controlled by a microcontroller GPIO, or a pull-up resistor if the used part supports enable via pulling up to Vcc.