Connecting Grounds in PCB Design

Thought for 1 min 31 sec

Short answer:

Yes. You don’t need to draw one big ground wire. Just place the Ground symbol wherever a node should be on GND; they are all the same GND net.
If you want multiple, separate grounds (e.g., analog vs digital), create additional ground nets using a portal-with-ground-symbol for each secondary ground and use those where needed.

What Flux documentation says: "In Flux, working with a single ground is very straightforward. Add a standard ground symbol to your schematic and simply wire it up. Flux will then take care creating a ground plane for you.

Working with multiple grounds is also straightforward in Flux, but simply requires adding a portal with a ground symbol for additional secondary grounds." Source

If you tell me whether you want a single GND or distinct grounds (AGND/DGND), I can help you set it up accordingly.

gooncocoon

Well, this circuit is entirely analog, so I think that will simplify things. I don’t care how many ground symbols there are, just that the power supply and the rest of the circuit are visually connected via said grounds for aesthetic purposes.

Thought for 1 min 36 sec

flux

Yes—use a single GND net and place as many ground symbols as you like for clarity. Every Ground symbol belongs to the same net, so the supply ground and the rest of the analog circuit are logically connected without drawing one long wire.

Working with multiple grounds is also straightforward in Flux, but simply requires adding a portal with a ground symbol for additional secondary grounds." Source

If you ever decide to show named connections instead of wires, you can also use Net Portal labels with the name “GND” for the same effect.

Use net portals

Single vs multiple grounds

Add secondary ground

Ground plane behavior

Schematic aesthetics

please explain what SW2 does.

gooncocoon

@copilot please explain what SW2 does.

copilot

In the context of your guitar pedal template, SW2 is a 3PDT (triple pole double throw) switch. A 3PDT switch is commonly used in guitar pedals to toggle between the effect circuit and a bypass, allowing the signal to pass through the pedal circuitry or to bypass it and go directly to the output.

Here’s a breakdown of its function and pin connections:

Function of SW2

True Bypass Switching: This 3PDT switch allows you to toggle between direct signal pass-through (bypass) and signal processing through the pedal's effect circuit. When bypassed, the input signal goes directly to the output, preserving the original signal without any modification by the effect circuitry.
LED Control: Often, one pole of the switch is used to control an LED to indicate whether the effect is on or bypassed.

Pins and Typical Connections

The TK-6580-1 3PDT switch has six pins configured as follows:

Pins 1 & 2 (First Pole): Used to connect the input signal to either the effect circuit input or the output jack directly.
Pins 3 & 4 (Second Pole): Used to connect the output of the effect circuit to the output jack when the effect is active or to bypass it.
Pins 5 & 6 (Third Pole): Often used to control an indicator LED.

Specific Connections in Your Schematic

Here's a list of connections involving SW2:

Connect SW1:Pin_1 to InputJack:P1 and InputJack:P1
Connect SW1:Pin_2 to CircuitOutput:P1
Connect SW1:Pin_3 to +9V:P1
Connect SW1:Pin_4 to GND:P1, J2:P2, J1:P2, and J3:P2
Connect SW1:Pin_5 to CircuitInput:P1
Connect SW1:Pin_6 to InputJack:P1 and InputJack:P1

You can use these connections to set up the true bypass circuitry as per standard guitar pedal designs.

Would you like a more detailed explanation of how to wire this switch for your pedal, or do you have another specific question?

Check that none of the unconnected pins require pull-up or pull-down resistors t...

gooncocoon

@copilot Check that none of the unconnected pins require pull-up or pull-down resistors to ensure proper function.

copilot

Let's review the unconnected pins or unspecified net connections for each component to determine if any might require pull-up or pull-down resistors. Here's a summary of the relevant components:

TL072CDT Op-Amps (U1, Tl702, TL702)
- Unconnected pins like inputs can be problematic in op-amps, requiring a defined state instead of floating.
- Ensure all input pins are connected to a definite potential or feedback network.
MAX1044CPA+ (U2)
- Pin 6 (LV): Left unconnected if low-voltage applications are not required. A pull-down may be needed if precise power-up conditions are required.
- Other pins should be connected as specified in the datasheet for proper functionality.
Switches (e.g., SW2, SW1)
- Switch inputs driving digital inputs may benefit from pull-up or pull-down resistors to define a state when open.
General Nets and Power Pins
- Unconnected power pins are connected; ensure bypass caps (typically 0.1uF) are close to the ICs.

For the above scenarios, do the following:

Op-Amps: Tie unused op-amp inputs to ground or a voltage reference through a suitable resistor (like 10kΩ).
Unused Pins on MAX1044CPA+: Confirm if any adjustments using its boost and LV pins are required in your application, pulling appropriately if necessary.
Switches: Could benefit from pull-up or pull-down resistors ($1k\Omega - 10k\Omega$) to prevent floating pin issues when the switch is open.

If you provide the full context, including the type of application, we can refine these recommendations. Additionally, check any special notes in datasheets for the most up-to-date recommendations.

R23

Resistance

4.7KΩ

R21

Resistance

1.8KΩ

Resistance

500 Ω

R30

Resistance

27KΩ

Resistance

500 Ω

R29

Resistance

27KΩ

R25

Resistance

560 Ω

R28

Resistance

100KΩ

R243

Resistance

68KΩ

R24

Resistance

100KΩ

Tl702

-8.6V

C14

Capacitance

3.9nF

C15

Capacitance

4.7uF

C22

Capacitance

1uF

+16.2V

C18

Capacitance

C19

Capacitance

1uF

-8.6V SRC PIN - U1 -VCC

+9V

+9V P1 - U1 +VCC

C20

Capacitance

Manufacturer Part Number

1N4001

Capacitance

12pF

Note 5

Line 1

This represents the output jack.

Line 2

P1: Tip

Line 3

P2: Sleeve

RV3-LEVEL 10Kb

Package or Case Code

Reviews

Generic Inductor
A generic fixed inductor suitable for rapid circuit topology development. The footprint automatically adapts based on the selected package, supporting standard SMD sizes (e.g., 0402, 0603, 0805) as well as well-known inductor packages such as SDR1806, PA4320, SRN6028, and SRR1260. Standard inductor values: 1.0 nH, 10 nH, 100 nH, 1.0 µH, 10 µH, 100 µH, 1.0 mH 1.2 nH, 12 nH, 120 nH, 1.2 µH, 12 µH, 120 µH, 1.2 mH 1.5 nH, 15 nH, 150 nH, 1.5 µH, 15 µH, 150 µH, 1.5 mH 1.8 nH, 18 nH, 180 nH, 1.8 µH, 18 µH, 180 µH, 1.8 mH 2.2 nH, 22 nH, 220 nH, 2.2 µH, 22 µH, 220 µH, 2.2 mH 2.7 nH, 27 nH, 270 nH, 2.7 µH, 27 µH, 270 µH, 2.7 mH 3.3 nH, 33 nH, 330 nH, 3.3 µH, 33 µH, 330 µH, 3.3 mH 3.9 nH, 39 nH, 390 nH, 3.9 µH, 39 µH, 390 µH, 3.9 mH 4.7 nH, 47 nH, 470 nH, 4.7 µH, 47 µH, 470 µH, 4.7 mH 5.6 nH, 56 nH, 560 nH, 5.6 µH, 56 µH, 560 µH, 5.6 mH 6.8 nH, 68 nH, 680 nH, 6.8 µH, 68 µH, 680 µH, 6.8 mH 8.2 nH, 82 nH, 820 nH, 8.2 µH, 82 µH, 820 µH, 8.2 mH #generics #CommonPartsLibrary
jharwinbarrozo
16.5k
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, 10000uF 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, 220pF, 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 Resistor
A generic fixed resistor ideal for rapid circuit topology development. Its footprint automatically adapts based on the selected package case code—supporting 0402, 0603, 0805, 1203, and many other standard SMD packages, as well as axial horizontal and vertical configurations. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0 ohm, 10 ohm, 100 ohm, 1.0k ohm, 10k ohm, 100k ohm, 1.0M ohm 1.1 ohm, 11 ohm, 110 ohm, 1.1k ohm, 11k ohm, 110k ohm, 1.1M ohm 1.2 ohm, 12 ohm, 120 ohm, 1.2k ohm, 12k ohm, 120k ohm, 1.2M ohm 1.3 ohm, 13 ohm, 130 ohm, 1.3k ohm, 13k ohm, 130k ohm, 1.3M ohm 1.5 ohm, 15 ohm, 150 ohm, 1.5k ohm, 15k ohm, 150k ohm, 1.5M ohm 1.6 ohm, 16 ohm, 160 ohm, 1.6k ohm, 16k ohm, 160k ohm, 1.6M ohm 1.8 ohm, 18 ohm, 180 ohm, 1.8K ohm, 18k ohm, 180k ohm, 1.8M ohm 2.0 ohm, 20 ohm, 200 ohm, 2.0k ohm, 20k ohm, 200k ohm, 2.0M ohm 2.2 ohm, 22 ohm, 220 ohm, 2.2k ohm, 22k ohm, 220k ohm, 2.2M ohm 2.4 ohm, 24 ohm, 240 ohm, 2.4k ohm, 24k ohm, 240k ohm, 2.4M ohm 2.7 ohm, 27 ohm, 270 ohm, 2.7k ohm, 27k ohm, 270k ohm, 2.7M ohm 3.0 ohm, 30 ohm, 300 ohm, 3.0K ohm, 30K ohm, 300K ohm, 3.0M ohm 3.3 ohm, 33 ohm, 330 ohm, 3.3k ohm, 33k ohm, 330k ohm, 3.3M ohm 3.6 ohm, 36 ohm, 360 ohm, 3.6k ohm, 36k ohm, 360k ohm, 3.6M ohm 3.9 ohm, 39 ohm, 390 ohm, 3.9k ohm, 39k ohm, 390k ohm, 3.9M ohm 4.3 ohm, 43 ohm, 430 ohm, 4.3k ohm, 43K ohm, 430K ohm, 4.3M ohm 4.7 ohm, 47 ohm, 470 ohm, 4.7k ohm, 47k ohm, 470k ohm, 4.7M ohm 5.1 ohm, 51 ohm, 510 ohm, 5.1k ohm, 51k ohm, 510k ohm, 5.1M ohm 5.6 ohm, 56 ohm, 560 ohm, 5.6k ohm, 56k ohm, 560k ohm, 5.6M ohm 6.2 ohm, 62 ohm, 620 ohm, 6.2k ohm, 62K ohm, 620K ohm, 6.2M ohm 6.8 ohm, 68 ohm, 680 ohm, 6.8k ohm, 68k ohm, 680k ohm, 6.8M ohm 7.5 ohm, 75 ohm, 750 ohm, 7.5k ohm, 75k ohm, 750k ohm, 7.5M ohm 8.2 ohm, 82 ohm, 820 ohm, 8.2k ohm, 82k ohm, 820k ohm, 8.2M ohm 9.1 ohm, 91 ohm, 910 ohm, 9.1k ohm, 91k ohm, 910k ohm, 9.1M ohm #generics #CommonPartsLibrary
jharwinbarrozo
1.5M
Ground
A common return path for electric current. Commonly known as ground.
jharwinbarrozo
20.5M
Terminal
An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
natarius
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
RMCF0805JT47K0
General Purpose Thick Film Standard Power and High-Power Chip Resistor 47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film Features: - RMCF – standard power ratings - RMCP – high power ratings - Nickel barrier terminations standard - Power derating from 100% at 70ºC to zero at +155ºC - RoHS compliant, REACH compliant, and halogen free - AEC-Q200 compliant
jharwinbarrozo
1.2M
875105359001
10 µF 16 V Aluminum - Polymer Capacitors Radial, Can - SMD 30mOhm 2000 Hrs @ 105°C #commonpartslibrary #capacitor #aluminumpolymer #radialcan
jharwinbarrozo
1.2M
CTL1206FYW1T
Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric)
jharwinbarrozo
1.1M
1070TR
Battery Holder (Open) Coin, 20.0mm 1 Cell SMD (SMT) Tab bate or batt #forLedBlink
jharwinbarrozo
700.5k

Project Name

DUAL OD SCHEMATIC/TATTOO

Description

IT'S HOOOOT

Properties

Properties describe core aspects of the project.

Pricing & Availability

Distributor	Qty 1
Arrow	$5.32–$5.79
Digi-Key	$4.96–$7.18
LCSC	$4.22–$11.46
Mouser	$5.90
Verical	$3.37–$3.76

Controls

Welcome 👋

Flux helps you build PCBs faster with an AI teammate!

Create your account to collaborate, stay updated, fork your own version, and get instant answers from our AI agent.