PCB Design for TA Sound System

flux

0:48

General (prev)
Chat History
Project
C14
C16
C32
C33
J6
R10
R9
Below is a consolidated summary of the PCB enhancements for your amplifier stage and overall design of the TA system in Flux.ai:

Table

FeatureDescription
1. Additional Test Points• TP_IN: At the audio input (from ESP32 or a signal generator). • TP_OUT: At the amplifier output (to the TA element). • TP_VCC: Along the 5V power rail near the LM386. • TP_GND: A common ground reference. • TP_BIAS: At the output side of the bias resistor across the TA element. Use small via test points with clear silkscreen labels.
2. Adjustable Gain• Add a 2-pin header with a jumper to enable/disable the gain capacitor (between LM386 pins 1 & 8). • Provide a footprint for a small 10kΩ potentiometer to replace the fixed input resistor, allowing manual amplitude adjustment.
3. Filtering Stages• Input Filter: RC low-pass filter using a 10kΩ series resistor and a 100nF capacitor to ground to reduce high-frequency noise. • Output Snubber: Footprint for an RC snubber (100Ω resistor + 100nF capacitor in series across the output) to dampen oscillations. • Power Filtering: Place a 100µF bulk cap and a 0.1µF ceramic cap close to the LM386 VCC pin—with an optional ferrite bead footprint on the VCC line.
4. Grounding Improvements• Use a split ground plane for analog (amp) and digital (ESP32) sections, tied together at a single star point near the power input. • Route sensitive analog traces (especially audio paths) away from noisy digital paths and consider guard traces or copper pours for added EMI suppression.
5. Optional PCB Enhancements• Power Indicator LED: Place an LED (with a series 1kΩ resistor) near the 5V input (e.g., LED → resistor → GND) to indicate power status. • Clear Silkscreen Labels: Use Flux’s Text Tool to tag test points (e.g., TP_IN, TP_OUT, GAIN_SEL, BIAS_V) and headers. • Mounting Holes: Add 2-4 mounting hole components (e.g., 3mm or 4mm diameter) near the board corners. • Rounded Corners: Edit the board outline with fillets (2–3mm radius). • Branding/Logo: Optionally add a silkscreen text such as “ThermoAmp v1.0 – Designed by Sara ⚡️”. • Header Pins for Probing: Include 2.54mm headers at key nodes (input, output, bias line). • Hacker Pads: Add unused small SMD pads (“solder pads”) as extra probing areas or for future add-on components. • Improved Ground Pour: Use Flux’s Polygon tool to create a continuous GND pour for enhanced EMI suppression.
Assumptions for the Design:
  • Amplifier Stage: Uses the LM386 with the internal gain set to 20× but enhanced externally to ~200× via a gain-setting capacitor between pins 1 and 8.
  • Biasing: A 100Ω resistor provides a 5V bias to the TA element (with an estimated current of 50 mA) and the load is approximately 8Ω.
  • Input Source: Coming from an ESP32 (PWM or DAC).
  • Power Supply: A regulated 5V rail, with proper decoupling near the LM386.
  • PCB Style: A compact, hand-solderable design using through-hole footprints where space permits.
Would you like to apply these enhancements as suggestions to your PCB design in Flux.ai? You can now click the "Apply changes" button to incorporate them.
288 days

Ready.

Sign up to send
J3
INT_ADC_DRDY
C7
Capacitance
1u F
J4
C13
Capacitance
1u F
C23
Capacitance
.1u F
R1
Resistance
10k Ω
C18
Capacitance
1u F
USBC2.0_D_N
C20
Capacitance
1u F
I2C_SDA
J5
PP3V3
USBC2.0_D_P
C10
Capacitance
1u F
I2C_SCL
PP3V3_SPI
C3
Capacitance
1u F
LOAD_CELL_A1_P
I2C_SCL
PP3V3
L1
Inductance
2.2n H
R4
Resistance
100 Ω
PP5V0
GPIO_SW1
LOAD_CELL_A1_P
I2C_SCL
C5
Capacitance
1u F
INT_ADC_DRDY
R5
Resistance
10k Ω
LOAD_CELL_AI_N
PP5V0
C21
Capacitance
10u F
GPIO_SW2
C14
Capacitance
100nF
C17
Capacitance
10u F
R2
Resistance
100 Ω
GPIO_SW1
C12
Capacitance
1u F
I2C_SDA
GPIO_SW2
C11
Capacitance
1u F
PP5V0
C6
Capacitance
1.2p F
PP5V0
LOAD_CELL_AI_N
C1
Capacitance
10u F
L2
Inductance
2.2n H
I2C_SDA
I2C_SDA
C32
Capacitance
100uF
I2C_SCL
R10
Resistance
100 Ω
PP3V3
C16
Capacitance
100nF
C33
Capacitance
0.1uF
R9
Resistance
10k Ω
SPI_MOSI
MCU_TXD
U1
Y2
L4
MCU_RXD
J6
MCU_BOOT
  • 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
    15.1k
  • 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

Inspect

ESPRSSO32 Smart Scale AI Auto Layout [Example]

ESPRSSO32 Smart Scale AI Auto Layout [Example]
Description

Created
Last updated by saramoremi0
1 Contributor(s)
saramoremi0

Controls

Properties

Availability & Pricing

DistributorQty 1
Arrow$3.81–$5.35
Digi-Key$6.29–$10.05
LCSC$6.71–$7.55
Mouser$8.04
Verical$2.57–$3.36

Assets