This project is a Smart Thermostat design using an ESP32 module for WiFi connectivity and a BME680 sensor for environmental monitoring. The user interface includes an E-ink display and an encoder for settings adjustment. Power is managed through a USB-C connector with a 3.3V regulator. #referenceDesign #project #ESP32 #ESP32WROOM #RF #WIFI #MCU #thermostat #referenceDesign #edge-computing #edgeComputing #espressif #template #reference-design

This is a reference design of the Bluetooth Low-Energy (BLE) temperature sensor. It uses an ESP32-MINI-1 microcontroller to connect to an SHT31-DIS-B2.5KS sensor. The sensor can be powered through connector J15, and additional components provide voltage regulation and derbiaising. Temperature data can be accessed via BLE. #referenceDesign #simple-embedded #espressif #template #reference-design

This MCP2544WFD -based reference design is a CAN bus transceiver circuit, providing reliable data communication over the CAN network. The design features a range of capacitors and resistors to ensure signal integrity, and a NUP2105L for voltage protection. It's ideal for applications requiring reliable data communication in an automotive or industrial environment. CANBus have block terminal connector and surface mount test points. #referenceDesign #project #CANbus #interface #transceiverCircuit #MCP2544WFD #MCP2544WFDT-H/MNY #template #canbus #microchip #reference-design

Raspberry Pi 2, 3, 4 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #RaspberryPi #HAT #RPi #template #project

Raspberry Pi 2, 3, 4, 5 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #Raspberry_Pi #Shield #RPi #template #part

Raspberry Pi 2, 3, 4 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #RaspberryPi #HAT #RPi #template #project

This project is a Smart Thermostat design using an ESP32 module for WiFi connectivity and a BME680 sensor for environmental monitoring. The user interface includes an E-ink display and an encoder for settings adjustment. Power is managed through a USB-C connector with a 3.3V regulator. #referenceDesign #project #ESP32 #ESP32WROOM #RF #WIFI #MCU #thermostat #referenceDesign #edge-computing #edgeComputing #espressif #template #reference-design

Board for low power projects based on ESP32. It has I2C connector, one UART connector, boot and reset buttons and RGB led #led #esp32 #sd #iot

This project is a plant care system that uses an ESP32-S3-MINI-1U-N8 microcontroller to automate plant care tasks. This system includes three Songle relays, multiple resistors, capacitors, and transistors, all powered at 3.3V, 5V, or 12V. It also incorporates a USB Type-C connector. #referenceDesign #edge-computing #edgeComputing #espressif #template #iot #ESP32 #relay #reference-design

Through Hole straight pin header, 01x04, 2.54mm pitch, single row #connector #pinheader #tht

3 Position Wire to Board Terminal Block Horizontal with Board 0.197" (5.00mm) Through Hole #screwblock #connector #commonPartsLibrary

Raspberry Pi 2, 3, 4, 5 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #Raspberry_Pi #Shield #RPi #template #part

Important Note: You must connect your own SPI/ICSP programming header if you want to burn the Arduino bootloader to the MCU. SMD Manufacturing: Need a hotplate and solderpaste Good to haves: - Oscillator Decoupling Caps Expose UART via connector Programming Button Onboard LED Reset Button You don't have to populate everything! Only these are mandatory: Reset Button Find the reference schematic here: https://www.arduino.cc/en/uploads/Main/ArduinoNano30Schematic.pdf

This project is a TCS3200D-TR color sensor circuit utilizing resistors, capacitors, LEDs, a JST connector, and a transistor for control. The color sensor allows for precise color identification and its output is accessible through a JST connector. #industrialSensing #colorSensor #referenceDesign #osramusa #template #reference-design

DIY handheld game console with EFM32TG11B120F, OLED 0.91" 128x32 I2C, 4 buttons (2 on each side), CR1220 battery connector, and USB Micro for charging. #Gaming #IoT #Microcontroller #EmbeddedSystems #EFM32

This project is a reference design for the VCNL3040 sensor interfaced via I2C. It includes a VCNL3040 ambient light sensor, a voltage regulator (AP2112K-3.3TRG1), an I2C level shifter using BSS138 MOSFETs, and necessary support components. Circuit interfaces through a JST connector. All components are powered by a 3.3V power source. #referenceDesign #industrialsensing #vishay #template #reference-design

Raspberry Pi 2, 3, 4 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #RaspberryPi #HAT #RPi #template #project

sEMG-DAQ is a wearable 6 channel data acquisition unit for capturing surface electromyographic (sEMG) signals from human arm muscles using SJ2-3593D jack connectors while conditioning, digitizing, processing and transmitting them as sEMG data to an external AI accelerated board through an SM12B-SRSS IDC connector where AI models are run for various applications including robotic control, muscle signals medical assessment and gesture recognition. The board leverages an INA125P instrumentation amplifier together with filter stages utilizing LM324QT op-amps for conditioning and an STM32G4A1VET6 microcontroller for the digitization, processing and data transmission of the signals. Since AI models can only be as good as the data, the design of such a DAQ is necessary to ensure clean, reliable and real-time data for AI applications requiring sEMG data. The board also has USB-FS and JTAG to cater for debugging. The power (5V) is fed through a screw terminal and is regulated by two LDK320AM LDO regulators to offer 5V, 3.3V and 1.8V to meet the requirements of various components on the board.

Board for low power projects based on ESP32. It has I2C connector, one UART connector, boot and reset buttons and RGB led

Arduino Uno R3 shield + very basic H bridge driver and connector

Raspberry Pi 2, 3, 4, 5 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #Raspberry_Pi #Shield #RPi #template #part

PIC16F877A-based load-cell measurement system using an HX711 24-bit ADC, 4 MHz crystal clock, load-cell connector, ICSP programming header, regulated 5V input, and low-noise PCB layout for internship deliverables.

Bilateral smart running insole data logger using two nearly identical ESP32-S3 pressure-sensing PCBs. Left variant is an ESP-NOW slave without microSD; right variant is the master with microSD logging. Both preserve the 16-zone FSR mux front end, LiPo charging, AP2112K regulation, USB-C charging input, JST battery connector, and the 280mm x 90mm 2-layer low-profile insole form factor.

M12 cable tester PCB for verifying straight-through 1-to-1 pin continuity between M12 connector types, with four LED indicator channels labeled by standard wire colors: pin 1 brown, pin 2 white, pin 3 blue, pin 4 black.

SCADA Sensor Node v2.1 using a Heltec WiFi LoRa 32 V4 module with separate +5V and board-generated +3V3 rails, ADS131M08 8-channel ADC front end, TCA9548A I2C multiplexer, TMP102-based fan control, ULN2003A relay and fan driver, CT/pressure/analog/One-Wire/vibration/humidity/Qwiic/flow/digital sensor interfaces, relay outputs, fan connector, brownout sensing, and a 200 mm x 140 mm 2-layer layout with Heltec keepout, antenna clearance, mounting holes, and DIN-rail slots.

Wearable health device prototype schematic with ECG sensing via AD8232, motion sensing via BNO085 or BMI270 IMU breakout, on-board processing using TI TM4C123G LaunchPad or MSPM0G3507 LaunchPad, optional ESP8266 Wi-Fi, LiPo battery charging with MCP73831, regulated 3.3 V power from TPS63031 buck-boost or AP2112 LDO prototype option, and user interfaces including electrode connector, JST battery connector, programming header, and optional on/off switch.

5V barrel-powered stepper motor controller board using a TMC2300 driver, a 4-wire JST-PH motor connector, and mechanical motor mounting with two 2 mm holes spaced 20 mm apart plus a centered 8 mm shaft hole.

Single-project implementation of the Blue Ant AMP Architecture Rev2 using one shared schematic with six logical board partitions: PCB-01 phono stage, PCB-02 input selector and relay attenuator interface, PCB-03 balanced driver and RCA-to-balanced conversion interface, PCB-04 dual logical power amplifier channels, PCB-05 multi-rail power supply, and PCB-06 isolated control and display. Explicit inter-partition connector interfaces and named nets preserve balanced signal handling after RCA conversion, distinct rail domains (+63V, -63V, +15V, -15V, +5V, +3.3V), and documented hard constraints including low-noise analog isolation and high-voltage domain separation.

SmartDeskPet v1.0 Shield Stage 1 status: - Goal: 5V input -> dual AMS1117-3.3 rails (+3V3_MCU and +3V3_WIFI) with common GND. - Note: Keep power nets explicitly named (avoid unnamed nets) to keep ERC happy. Stage 1 completion checklist: - Mark J1 Pin_1 (+5V) as a Power Output pin to satisfy ERC power-driver checks. - Verify all GND symbols/returns are on the same GND net. - Keep +5V_SERVO isolated from the main +5V net (only share GND). Stage 2 preparation notes (MPN/LCSC + layout constraints): - MPN/LCSC targets to define before Stage 2 exit: - AMS1117-3.3 (SOT-223): set exact MPN and (optionally) LCSC PN for both U1 and U2. - 100nF capacitor (0603): set MPN/LCSC for all 0603 100nF decouplers. - 4.7k resistor (0603): set MPN/LCSC for I2C pull-ups R1 and R2. - 1000uF bulk capacitor (radial): set MPN/LCSC for C7 (CP_Radial_D10.0mm_P5.00mm). - DC005 power jack/regulator input: select exact DC005 footprint + MPN/LCSC (if used). - 2.54mm headers/sockets: set MPN/LCSC for H1, H2, J1, J3, J4, J5, P3, P4, P5, and J2. - ESP-01S antenna keepout: - Reserve a copper keepout under and in front of the ESP-01S onboard antenna. - No copper pours/traces/components in the antenna region (top and bottom) per module guidelines. - H1/H2 header spacing: - Maintain 1000 mil spacing between H1 and H2 header centerlines (shield mechanical requirement). - Silkscreen placeholders: - Add silkscreen labels for: 5V IN, GND, +3V3_MCU, +3V3_WIFI, SERVO1, SERVO2, I2C SDA/SCL, DHT11, ASRPRO UART2, ESP-01S UART3. - Add placeholder text for: MPN, LCSC, board revision, and date code. Stage 3 layout constraints (placement and routing guidance): - Connector placement strategy: - Place H1 and H2 first to lock the shield mechanical interface; enforce 1000 mil spacing. - Place J1 and any DC005 input at the board edge for easy access. - Designated power area planning: - Group U1, U2, and C7 near the 5V entry point; keep high-current 5V and regulator loops short. - Use wide copper for +5V and any servo supply; stitch GND around power section. - Antenna keepout boundaries: - Place J2 (ESP-01S socket) at a board edge with the antenna facing outward. - Enforce a top-and-bottom copper keepout in the antenna region; keep noisy power traces away.

40×30 mm 4-Layer FCBoard with dual JST-GH 1.25 mm top-entry GH-6 connectors for PWR1/PWR2, SWD 1.27 mm debug-only connector, dual 5 V ideal-diode ORing, isolated USB_5V, dedicated nets (PWR1_5V, PWR2_5V, 5V_IO, 5V_SENS, 3V3_MCU, 3V3_IMU_A/B/C), per-IMU LDOs with inline ferrites and decoupling, and MCU VDDA ferrite isolation #JSTGH #CubeGrade #PowerArchitecture #FCBoard

Architectural Lavender Translation Collar – ESP32‑S3 Wi‑Fi + LoRa, USB‑C, Li‑ion, low‑power design Overview Experience a cutting-edge IoT solution with this low‑power board built around the ESP32‑S3‑MINI‑1‑N8. Designed for seamless Wi‑Fi (2.4 GHz), BLE, and LoRa (868 MHz) connectivity, this board integrates ENS161 and ENS210 sensors over I2C alongside an RFM95W‑868 LoRa radio on SPI. It is powered via a 3.7 V Li‑ion cell with USB‑C charging up to 500 mA, complete with full battery protection, a robust 3.3 V rail tailored for Wi‑Fi burst currents, and per‑peripheral power gating to enhance energy efficiency. Core Features • MCU: ESP32‑S3‑MINI‑1‑N8 equipped with an onboard PCB antenna for 2.4 GHz Wi‑Fi/BLE, ensuring optimal wireless performance. • Sensors: Integrated ENS161 and ENS210 sensors utilize a shared I2C bus with controllable 4.7 kΩ pull‑ups for streamlined communication. • LoRa Radio: The RFM95W‑868 module, connected via SPI, enables long‑range communication at 868 MHz. Power & USB‑C Connectivity • Battery: A reliable 3.7 V 1200 mAh Li‑ion battery connected via a right‑angle JST‑PH 2‑pin connector features built‑in battery protection. • Charging: The USB‑C receptacle, with CC resistors and TVS protection on D+/D− along with series resistors, supports fast, safe charging with a current limit of 500 mA. • Regulation: A dedicated 3.3 V regulator capable of handling Wi‑Fi burst currents coupled with bulk and high‑frequency decoupling ensures stable operation, supported by status LEDs indicating power and charge states. Low‑Power Control • Peripheral Management: Load switches allow selective power‑gating of the ENS161, ENS210, and RFM95W modules, controlled directly by ESP32‑S3 GPIOs. • Energy Efficiency: Controllable I2C pull‑ups minimize idle current, vital for prolonged battery life in IoT applications. RF and Antenna Integration • 2.4 GHz: Utilizes the integrated PCB antenna on the ESP32‑S3 with proper ground/metal keep‑out zones for optimal signal integrity. • 868 MHz: Features a controlled‑impedance feed from the RFM95W to a PI matching network (C‑L‑C pads) with flexible antenna options—selectable via SMA connector, chip antenna, or PCB trace—and includes RF ESD protection. Connectivity & Debug Features • USB‑C Interface: Provides secure data connectivity with integrated safeguards and proper terminations. • Debugging: A comprehensive programming/debug header exposes EN, BOOT, and UART lines, with test points on key rails and buses (3V3, VBAT, SCK, MOSI, MISO, SDA, SCL, RESET/EN, GND) to simplify development and troubleshooting. Design Verification • Rigorous ERC/DRC and decoupling checks ensure adherence to component ratings and optimal signal routing. • Maintain RF keep‑outs and impedance‑controlled traces for both 2.4 GHz and 868 MHz paths, securing reliable performance even during high‑intensity operations. #IoT #ESP32S3 #LoRa #LowPowerDesign #USB-C #WirelessConnectivity #BatteryPowered #RFDesign

Compact MPPT Solar-Powered Dusk-to-Dawn 0.5 W LED Light with NCP3065 SEPIC Buck-Boost Driver, BQ24650 MPPT Charger, MIC845 Comparator, Vertical JST-PH 2-Pin Battery Connector, Off-Board Solar Input Pads/Optional Connector, Centered Backside LED, 1.4 mm Perimeter Clearance #SEPIC #NCP3065

4-Channel Secure 433 MHz Automotive Relay Receiver with STM32G071 and RFM69HCW, featuring a 16-pin Digi-Key right-angle ≥10 A/circuit connector, 2 oz copper 10 A traces, AEC-Q200 Digi-Key control passives, and verified LED/pushbutton wiring #automotive #433MHz #STM32G0 #RFM69 #relays #10A #2ozCopper #AECQ200

TECHNICAL ASSIGNMENT AND DESIGN GUIDE Active Three-Way Crossover on NE5532 Powered by AM4T-4815DZ and Amplifiers TPA3255 (Updated Version) 1. GENERAL PURPOSE OF THE DEVICE The goal of the development is to create an active three-way audio crossover for one channel of a loudspeaker system, working with the following drivers: LF: VISATON W250 MF: VISATON MR130 HF: Morel MDT-12 Each frequency range is amplified by a separate power amplifier: LF: TPA3255 in PBTL mode (mono) MF + HF: second TPA3255 in stereo mode (one channel for MF, the other for HF) The crossover accepts a single linear audio signal (mono) and divides it into three frequency bands: Range Frequency Range LF 0 – 650 Hz MF 650 – 2500 Hz HF 2500 Hz and above Filter type: Linkwitz–Riley 4th order (24 dB/oct) at each crossover point (650 Hz and 2500 Hz). The crossover must provide: minimal self-noise; no audible distortion in the audible range; stable operation with NE5532 at ±15 V power supply; easy adjustment of the level for each band, as well as the overall level (via the input buffer). 2. FILTER TYPES AND BASIC OPERATING PRINCIPLES Each filter is implemented as two cascaded Sallen–Key 2nd order (Butterworth) stages, resulting in a final 4th order LR4 filter. Topology: non-inverting Sallen–Key, optimal for NE5532. For all stages: Cascade gain: K ≈ 1.586 This provides a Q factor of 0.707 (Butterworth), which in combination gives a Linkwitz–Riley 4th order. 3. COMPONENT VALUES FOR FILTERS 3.1 Universal Parameters RC chain capacitors: 10 nF, film capacitors, tolerance ≤ 5% Resistors: metal-film, tolerance ≤ 1% The gain of each stage is set by feedback resistors: Rf = 5.9 kΩ Rg = 10 kΩ K ≈ 1 + (Rf / Rg) ≈ 1.59 The circuit should allow for the installation of a small capacitor (10–47 pF) in parallel with Rf (footprint provided) for possible stability correction (not mandatory to install in the first revision). 3.2 650 Hz Filters (Low-frequency boundary for MF) These are used for the division between W250 and MR130. LP650 — Low-frequency Filter 2nd Order R1 = 24.9 kΩ R2 = 24.9 kΩ C1 = 10 nF C2 = 10 nF Two stages: LP650 #1 and LP650 #2. HP650 — MF High-frequency Filter 2nd Order Same values: R1 = 24.9 kΩ R2 = 24.9 kΩ C1 = 10 nF C2 = 10 nF Two stages: HP650 #1 and HP650 #2. 3.3 2500 Hz Filters (Upper boundary for MF) These are used for the division between MR130 → MDT-12. LP2500 — High-pass MF Filter R1 = 6.34 kΩ R2 = 6.34 kΩ C1 = 10 nF C2 = 10 nF Two stages: LP2500 #1 and LP2500 #2. HP2500 — High-frequency Filter Same values: R1 = 6.34 kΩ R2 = 6.34 kΩ C1 = 10 nF C2 = 10 nF Two stages: HP2500 #1 and HP2500 #2. 4. OPERATIONAL AMPLIFIERS The NE5532 (dual op-amp, DIP-8 or SOIC-8) is used. A minimum of 4 packages (8 channels) for filters: NE5532 Function U1A, U1B LP650 #1, LP650 #2 (LF) U2A, U2B HP650 #1, HP650 #2 (Lower MF cut-off) U3A, U3B LP2500 #1, LP2500 #2 (Upper MF cut-off) U4A, U4B HP2500 #1, HP2500 #2 (HF) Additionally: U5 — input buffer / preamplifier (both channels) If necessary, an additional NE5532 (U6) for the balanced input (see section 6.2). All NE5532 should have local decoupling for power supply (see section 5.1). 5. CROSSOVER POWER SUPPLY AM4T-4815DZ DC/DC module is used: Input: 36–72 V, connected to the 48 V power supply for TPA3255 amplifiers. Output: +15 V / –15 V, up to 0.133 A per side. Maximum output capacitance: ≤ 47 µF per side (according to the datasheet). 5.1 Power Filtering Input (48 V): RC variant (simpler, acceptable for the first revision): R = 1–2 Ω / 1–2 W C = 47–100 µF (for 63 V or higher) LC variant (preferred for improved noise immunity): L = 10–22 µH C = 47–100 µF The developer may implement LC if confident in choosing the inductance and its parameters. Output +15 V and –15 V (general filtering): Electrolytic capacitor 10–22 µF per side 100 nF (X7R) per side to GND Local decoupling for NE5532 (REQUIRED): For each NE5532 package: 100 nF between +15 V and GND 100 nF between –15 V and GND Place as close as possible to the op-amp power pins (short traces). Additional local filtering for power lines: For each NE5532, decouple from the ±15 V main rails: Either 4.7–10 Ω resistor in series with +15 V and –15 V, Or ferrite bead in each rail. After this component, place local capacitors (100 nF + 1–4.7 µF) to ground. 6. INPUT TRACT: INPUTS, BUFFER, ADJUSTMENT 6.1 Unbalanced Input (RCA / Jack / Linear) The main mode is the unbalanced linear input, for example, RCA. Input tract structure: RF-filter and protection: Signal → series resistor Rin_series = 100–220 Ω After resistor — capacitor Cin_RF = 470–1000 pF to GND This forms a low-level RF filter and reduces high-frequency noise. DC-block (low-pass HP-filter): Capacitor Cin_DC = 2.2–4.7 µF film in series Resistor to ground Rin_to_GND = 47–100 kΩ Cut-off frequency — negligible in the audio range but removes DC. Input buffer / preamplifier (NE5532, U5): Non-inverting configuration. Input — after DC-block. Gain: adjustable, e.g., Rg_fixed = 10 kΩ (to GND through trimmer) Rf = 10–20 kΩ + footprint for trimmer (e.g., 20 kΩ) The gain should be in the range of 0 dB to +10…+12 dB. Possible configuration: Rg = 10 kΩ fixed Rf = 10 kΩ + 10 kΩ trimmer in series. This allows adjusting the overall level of the crossover according to the source and amplifier levels. Buffer output: A low-impedance output (after NE5532) This signal is simultaneously fed to the inputs of all filters: LP650 (LF) HP650 → LP2500 (MF) HP2500 (HF) 6.2 Balanced Input (XLR / TRS) — Optional, but laid out on the board The board should allow for a balanced input, even if it’s not used in the first revision. Implementation requirements: XLR/TRS connector (L, R, GND) or separate 3-pin header. Simple differential receiver on NE5532 (extra U6 package or use one channel of U5 if sufficient). Circuit: classic instrumentation amplifier or differential amplifier: Inputs: IN+ and IN– Output — single-ended signal of the same level (or slightly amplified), fed to DC-block and buffer (or directly to the buffer if integrated). Switching between balanced/unbalanced mode: Implement using jumpers / bridges or adapters: Either switch before the buffer, Or use two separate pads, one of which is unused. All balanced input grounds must be connected to the same AGND point as the unbalanced input to avoid ground loops. 7. LEVEL ADJUSTMENT OF BANDS (BEST METHOD) The level adjustment of each band (LOW, MID, HIGH) is required to match the sensitivity of the speakers and amplifiers. Recommended method: After each full filter (after LP650×2, MID-chain HP650×2 → LP2500×2, HP2500×2), install: A passive attenuator: Series: Rseries (0–10 kΩ, adjustable) Shunt: Rshunt to GND (10–22 kΩ, fixed or adjustable) For simplicity and reliability: Implementation on the board: For each band (LOW, MID, HIGH) provide: Pad for multi-turn trimmer 10–20 kΩ as a divider (between signal and ground) in the "level adjustment" configuration. If adjustment is not needed — install a fixed divider (two resistors) or simply use a jumper. It is preferable to use: For setup: multi-turn trimmers 10–20 kΩ, available on the top side of the board. Nominals for the initial configuration can be selected through measurements, but the PCB should have flexibility. This provides: Accurate balancing of band volumes without interfering with the filters; Flexibility for fine-tuning to the specific characteristics of the speakers. 8. INPUTS AND OUTPUTS OF THE CROSSOVER (FINAL) 8.1 Inputs 1× Unbalanced linear input (RCA or 3-pin header) 1× Balanced input (XLR/TRS or 3-pin header) — optional, but space must be provided on the board. Input impedance (unbalanced after RF-filter): 22–50 kΩ. The input tract must be implemented using shielded cables. 8.2 Outputs Outputs to amplifiers: Output Signal LOW OUT After LP650×2 (LF) MID OUT After HP650×2 → LP2500×2 (MF) HIGH OUT After HP2500×2 (HF) Each output: Series resistor 100–220 Ω (prevents possible oscillations and simplifies cable management). A nearby own AGND pad (ground output), so the signal pair SIG+GND runs together. Outputs should be compactly placed on 2-pin connectors (SIG+GND) or 3-pin (SIG+GND+reserve). 9. PCB DESIGN REQUIREMENTS 9.1 Board Number of layers: 2 layers Bottom layer: solid analog ground (AGND). 9.2 Component Placement Key principles: RC chains of each filter (R1, R2, C1, C2, Rf, Rg) should form a compact "island" around the corresponding op-amp. If elements are placed too far apart, the filter will not work correctly (calculated frequency and Q will shift). Feedback tracks (Rf and Rg) should be as short and direct as possible. The AM4T-4815DZ module should be placed: Far from the input buffer, Far from the first filter stages, If necessary, make a "cutout" in the ground under it to limit noise propagation. Place the input connector, RF-filter, and buffer on one side of the board, and the output connectors on the opposite side. 9.3 Ground The entire audio circuit uses one analog ground: AGND. Connect AGND to the power ground (48 V and amplifiers) at one point ("star"). The star should be implemented as: One point/pad where: The ground of the input, The ground of the filters, The ground of the outputs, The ground of the DC/DC. Avoid long narrow "ground" jumpers — use wide polygons with a single connection point. 9.4 Placement of Output Connectors Group LOW/MID/HIGH compactly. Each should have its own GND pad nearby. Route the SIG+GND pairs as signal pairs, avoiding large loops. 10. ADDITIONAL ELEMENTS: PROTECTION, TEST POINTS 10.1 Test Points (TP) Be sure to provide test points (pads): TP_IN — crossover input (after buffer) TP_LOW — LF filter output TP_MID — MF filter output TP_HIGH — HF filter output TP_+15, TP_–15, TP_GND — power control This greatly simplifies debugging with an oscilloscope. 10.2 Power Protection On the 48 V input — it is advisable to provide: Diode/scheme for reverse polarity protection (if possible), TVS diode or varistor for voltage spikes (optional). 10.3 Possible Stability Correction Pads for small capacitors (10–47 pF) in parallel with Rf in buffers and, if necessary, in some stages — in case of stability issues (this can be not installed in the first revision, but footprints should be provided). 11. BILL OF MATERIALS (BOM) Operational Amplifiers: NE5532 — 4 pcs (filters) NE5532 — 1–2 pcs (input buffer and balanced input) Total: 5–6 NE5532 packages. Resistors (1%, metal-film): 24.9 kΩ — 8 pcs 6.34 kΩ — 8 pcs 10 kΩ — ≥ 12 pcs (feedback, buffers, etc.) 5.9 kΩ — 8 pcs 22 kΩ — 1–2 pcs (input, auxiliary chains) 47–100 kΩ — several pcs (DC-block, input) 100 kΩ — 1 pc (if needed) 100–220 Ω — 4–6 pcs (outputs, RF, protection) 4.7–10 Ω — 2 pcs for each op-amp or group of op-amps (power filtering) — quantity to be clarified during routing. Trimmer Resistors: 10–20 kΩ multi-turn — one for each band (LOW, MID, HIGH) 10–20 kΩ — 1–2 pcs for the input buffer (overall gain adjustment). Capacitors: 10 nF film — 16 pcs (RC filters) 2.2–4.7 µF film — 1–2 pcs (input DC-block) 10–22 µF electrolytic — 2–4 pcs (DC/DC outputs) 1–4.7 µF (X7R / tantalum) — 1 pc for local power filtering (optional). 100 nF ceramic X7R — 10–20 pcs (local decoupling for each op-amp) 470–1000 pF — 1–2 pcs (RF filter on the input) 10–47 pF — optional for stability correction (Rf). Power Supply: AM4T-4815DZ — 1 pc Inductor 10–22 µH (if LC filter) — 1 pc R 1–2 Ω / 1–2 W — 1 pc (if RC filter). Connectors: Input (RCA + 3-pin for internal input) Balanced (XLR/TRS or 3-pin header) Outputs LOW/MID/HIGH — 2-pin/3-pin connectors. 12. TESTING RECOMMENDATIONS 12.1 First Power-up Apply ±15 V without installed op-amps. Check with a multimeter: +15 V –15 V No short circuits in the power supply. Install the op-amps (NE5532). Apply a sine wave of 100–200 mV RMS (signal generator). Check with an oscilloscope at TP: LP650 — should pass LF and roll off everything above 650 Hz. HP650 — should roll off LF, pass everything above 650 Hz. LP2500 — should roll off above 2500 Hz. **HP250 0** — should pass everything above 2500 Hz. 12.2 Phase Check The Linkwitz–Riley 4th order should give a flat frequency response when summed at the crossover points. This can be verified with REW/Arta. 12.3 Noise Check If there is noticeable "shshsh" or whistling: Check: Grounding layout (star) Placement and filtering of AM4T-4815DZ Presence and proper installation of all 100 nF and local filters. 13. FINAL RECOMMENDATIONS FOR BEGINNERS Do not rush, build the circuit step by step: input → buffer → one filter → test, then continue. Check component values at least twice before soldering. Filters should be routed as compact "islands" around the op-amp, do not stretch R and C across the board. Always remember the rule: "The feedback trace should be as short as physically possible." Before ordering the PCB, make a "paper prototype": print at 1:1, cut it out, place real components to check everything fits.

Teensy 4.1 SPI Communication with IIS3DWB Eval Board via 3.3V Plug-On Connector (No SD Card)

Mechanical Compatibility Verification: DE-15 Male Through-Hole Connector vs TE 6318977-3 Footprint

Daddy's second circuit board. A sign to let my wife know when I'm on a call. Activates with a slide switch and is powered by USB-C. R2 changes: -Moving to Letter Modules for ease of design -Adding ESP32 for WiFi On/Off and intensity control -Optional: Add unpopulated AA Battery Holder for battery option R1 changes: -Changed LED part to Red LEDs -adjusted resistor value of buck converter -Changed source for USB-C Connector -Removed exposed soldermask on buck converter with negative soldermask expansion -Order with black soldermask Modified by markwu2001: Adjustable Brightness, 85-90% Drive Efficiency <5W Operation (Can use 5V 1A Plug) This project can be purchased from LCSC

Through Hole straight pin header, 01x08, 2.54mm pitch, single row #connector #pinheader #tht

Through Hole straight pin header, 01x07, 2.54mm pitch, single row #connector #pinheader #tht

Raspberry Pi 2, 3, 4, 5 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #Raspberry_Pi #Shield #RPi #template #part

I want to make the hardware and software for a 5.2 inch diameter capacitive touch screen display. Please give me all of the information the enable me to do this, I have NO experience of code or PCB design or manufacture. I want to measure a battery voltage and amps used via a coulomb counter to indicate a fuel level indicator icon I just want two connections + and - Its not single cell, its a battery of 20 cells LIFEPO4 each cell is 3.2v nominal and 100a I also want to include a can bus controller to read and display motor rpm And can bus temperature Also a GPS speedometer, odometer and trip. Toggle between knots, mph and kmh by touchscreen, Also toggle between nautical miles, km and miles with a Trip meter reset. Startup screen animation, Speed Incremental bar Plus a digital reading, And an animated compass heading STM32 or ESP32 Please recommend all hardware, I have the can protocol for the motor controller but not with me right now Connection via a 4 pin military connector can high can low +v and –v Top middle of screen incremental speed bar that fills 120 degrees with 60 degrees being top dead centre in an arc Dead middle of screen DIGITAL SPEED To the left of dead middle a Compass To the right of dead centre DIGITAL RPM Next line with a space between dead centre will be the ODOMETER, Trip and Battery level Below those are the Toggle buttons Heading compass by GPS, no WiFi or Bluetooth Write full GPS parsing code for my firmware Can you write the code with all of your recommendations for smoother bug free operation Can a FRAM replace the sd card ALL components must fit onto one board into an enclosure directly behind the screen that measures 5.0 inches diameter x 13mm deep inside dimensions

USB-C (USB TYPE-C) USB 3.2 Gen 2 (USB 3.1 Gen 2, Superspeed + (USB 3.1)) Plug Connector 24 Position Board Edge, Straddle Mount #commonpartslibrary #connector #usbc

20-W MONO CLASS-D AUDIO POWER AMPLIFIER with terminal block connector for a speaker #audioDevices

Raspberry Pi 2, 3, 4 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #RaspberryPi #HAT #RPi #template #project

Raspberry Pi 2, 3, 4 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #RaspberryPi #HAT #RPi #template #project

R2 w Thread changes: -Moving to Letter Modules for ease of design -Adding MGM210L for Matter on Thread On/Off and intensity control -Shifted A and R letters closer to fix Kerning -Optional: Add unpopulated AA Battery Holder for battery option R1 changes: -Changed LED part to Red LEDs -adjusted resistor value of buck converter -Changed source for USB-C Connector -Removed exposed soldermask on buck converter with negative soldermask expansion -Order with black soldermask Modified by markwu2001: - Adjustable Brightness, - 85-90% Drive Efficiency - <5W Operation (Can use 5V 1A Plug) This project can be purchased from LCSC Original Description: Daddy's second circuit board. A sign to let my wife know when I'm on a call. Activates with a slide switch and is powered by USB-C. #template #arduino-matter

Raspberry Pi 2, 3, 4 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #RaspberryPi #HAT #RPi #template #project

Raspberry Pi 2, 3, 4 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #RaspberryPi #HAT #RPi #template #project

ESP32 Water Meter is a board designed to accurately measure water usage using an ESP32 microcontroller. It integrates built-in Wi-Fi, Bluetooth, and BLE for seamless data transmission and remote monitoring. The design incorporates essential components such as a linear voltage regulator, USB-C connector for power and programming, fuse, and TVS diode for circuit protection. This robust solution offers reliable power management and sensor integration, making it ideal for IoT applications in water metering and resource monitoring. #ESP32WaterMeter #IoT #WaterMeter #ESP32 #DataTransmission #PowerManagement #ElectronicsDesign #PCBDesign

Raspberry Pi 2, 3, 4, 5 or 400 Model B+ connector with RPi board outline and mounting holes. good for Raspberry Pi Shield projects. Insulation Height 0.335" (8.51mm) Compatible part number: PPPC202LFBN-RC #Raspberry_Pi #Shield #RPi #template #part