The PAM8610, manufactured by Power Analog Microelectronics, is a high-performance, 10W (per channel) stereo class-D audio amplifier featuring DC volume control. This component is designed to deliver low THD+N (0.1%), low EMI, and high efficiency (>90%), making it ideal for high-quality sound reproduction in a variety of applications such as flat monitor/LCD TVs, multi-media speaker systems, DVD players, game machines, boomboxes, and musical instruments. Operating off a 7V to 15V supply, the PAM8610 distinguishes itself with its 32-step DC volume control ranging from -75dB to 32dB, shutdown/mute/fade functions, and comprehensive protection against overcurrent, thermal, and short-circuit conditions. Its low quiescent current, pop noise suppression, and minimal external component requirement further enhance its appeal for compact and efficient audio solutions. The PAM8610 is available in a compact 40-pin QFN 6mm*6mm package, ensuring a small footprint for space-constrained applications. Compliance with RoHS standards underscores its environmental consideration. With its advanced features and high integration level, the PAM8610 offers a compelling option for designers seeking to incorporate robust audio amplification with fine-grained volume control in their electronic projects.

Arduino Micro - MIDI Controller It uses the Arduino Micro as USB midi controller. It has 1 capacitive touch octave (12 Keys), 2 rotary encoders, a button, and a proximity sensor that can be used as a mod wheel, sustain pedal or MPE. The oled screen displays the different configuration options. It can be set to any channel or C.C. so it can be used to modify other instruments behavior. The capacitive touch keys can also be used as 12 drum machine pads.

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.

Ultra-Compact 4-Layer ESP32-C6 and BG95-M3 LTE Development Board with Onboard eSIM, π-Match RF Tuning, Controlled Impedance Routing, and Optional u.FL Connector

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

Compact 2-Layer ESP32-WROOM-32E Ultrasonic Emitter Board with USB-C Auto-Programming, On-Board 12 V→3.3 V Buck, 3× Low-Side MOSFET Drivers, Optional U.FL Antenna, ESD/TVS Protection, RF/Power Partitioning, and Named Nets (PWR_12V_IN, 3V3, GND, DRV_CH1/2/3, LED_PWR/LED_NET/LED_EMIT) #ultrasonic #ESP32 #RFDesign #PowerDesign #PCBDesign

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

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

1.1 BLE Beacon Tags – Dual-Mode (BLE + LoRa) Installation: Mounted on safety helmets. Specification Requirement Communication Protocols BLE 5.0+ and LoRaWAN 1.0.4 Class A/B BLE Range Up to 150 meters LoRa Range > 5 km Battery Life BLE: ≥ 5 years; LoRa: ≥ 8 years Indoor Accuracy 1–5 meters using BLE Outdoor Accuracy 1–10 meters using LoRa + IMU + AI (no GPS on tag) Sensors 3-axis IMU, optional T&H, fall detection Alert Features SOS button, red LED, buzzer, vibration motor IP Rating IP67 minimum Operating Temperature -20°C to +70°C Certifications IECEx, IPSEC, FCC, CE, RoHS, REACH Branding White label with client logo

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

This project is focused on designing a highly efficient PCB for a switching power supply using a robust selection of electronic components. Our design leverages a flyback topology featuring a ferrite transformer (options EE25 or EE33), a PWM integrated circuit (TL494, SG3525, or UC3842), and a power MOSFET (IRF840 or a similar alternative) for effective high-voltage switching. Fast and reliable rectification is ensured by using a Schottky diode (MBR20100 or FR107) along with a rectifier bridge built from four 1N4007 diodes or a dedicated 4A bridge. Key stabilization and regulation components include the TL431 reference regulator and a Zener diode for precise voltage control in critical areas. For input and output filtering, the design incorporates electrolytic capacitors (470 µF, 25 V for output and 400 V, 100 µF for input) and ceramic capacitors (ranging from 1 nF to 100 nF) to limit high-frequency noise. Additional safety and operational features are provided by an NTC (soft-start thermistor) to prevent current spikes, various resistors (from 1 Ω to 100kΩ), an optocoupler (PC817) for signal isolation, a switch, and a protection fuse. Before moving forward with a finalized PCB layout and schematic details, we need to clarify a few design choices: 1. Transformer Choice: Would you prefer using the EE25 or the EE33 ferrite transformer variant as the heart of the switching power supply design? This detailed approach ensures that the power supply not only meets rigorous performance and safety standards but also supports a reliable and scalable solution for various electronic applications. #PCBDesign #SwitchingPowerSupply #Electronics #SMPS #PowerElectronics #FlybackConverter #CircuitDesign #ElectronicsComponents

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 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

This is the project template for the Raspberry Pi Pico 2, the latest addition and update to Pi Pico line up. Raspberry pi pico 2 is equipped with the RP2350, a cutting-edge, high-performance microcontroller designed with enhanced security and versatility in mind. Every element of its design has been upgraded, from the advanced CPU cores to the innovative PIO (Programmable I/O) interfacing subsystem. The Raspberry Pi Foundation has integrated a robust security architecture centered around Arm TrustZone for Cortex-M, ensuring data protection and integrity. Additionally, new low-power states and expanded package options broaden the range of applications, making the Pico 2 an ideal choice for diverse, power-sensitive projects. To learn more about what's the key differences between the original Pi Pico and the new Pi Pico 2, read our blog https://www.flux.ai/p/blog/whats-new-in-the-raspberry-pi-pico-2-a-showdown-with-the-original-raspberry-pi-pico #project-template #template #raspberry #pi #pico2 #newpico

The AO3414 from Alpha & Omega Semiconductor is an N-Channel Enhancement Mode Field Effect Transistor (FET) leveraging advanced trench technology to deliver excellent RDS(ON), low gate charge, and reliable operation with gate voltages as low as 1.8V. Engineered for applications requiring reliable load switching or precise control in PWM circuits, the AO3414 is well-suited for high-efficiency performance. This component features a maximum drain-source voltage (VDS) of 20V and supports a continuous drain current (ID) of 4.2A at VGs of 4.5V. Distinguishing characteristics include RDS(ON) values of less than 50mΩ at VGS = 4.5V, 63mΩ at VGS = 2.5V, and 87mΩ at VGS = 1.8V, ensuring minimal power loss and optimal thermal efficiency. Packaged in a compact TO-236 (SOT-23) form factor, it meets Pb-free standards and is available as the AO3414L for a Green Product option, both versions maintaining electrical equivalence. The AO3414 also boasts fast switching times and robust thermal performance, with comprehensive specifications confirming its suitability for high-performance consumer electronics.

The AO3414 from Alpha & Omega Semiconductor is a N-channel enhancement mode field-effect transistor (FET) that utilizes advanced trench technology to offer exceptional performance characteristics, including low RDS(ON), minimal gate charge, and compatibility with gate voltages as low as 1.8V. This component is specifically designed for use in load-switching and PWM applications. The AO3414 is a Pb-free product meeting ROHS and Sony 259 specifications, with an option for a Green Product under part number AO3414L. Both variants are electrically identical. Key specifications include a drain-source voltage (VDS) of 20V, a continuous drain current (ID) of 4.2A at VGS=4.5V, and various RDS(ON) values depending on the gate voltage, with a maximum of 87mΩ at VGS=1.8V. Encased in the TO-236 (SOT-23) package, the AO3414 features a maximum power dissipation of 1.4W at 25℃ and a junction-to-ambient thermal resistance of 90°C/W. This robust FET additionally offers a commendable forward transconductance of 11 S and a low total gate charge of 6.2 nC, making it an efficient choice for high-performance applications.

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 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

The OPA835 and OPA2835 from Texas Instruments are ultra-low-power, rail-to-rail output, voltage-feedback (VFB) operational amplifiers. Designed for high-performance applications, these single (OPA835) and dual (OPA2835) op-amps operate over a power supply range of 2.5 V to 5.5 V. Consuming a mere 250 µA per channel, they offer a remarkable balance of power efficiency and performance, boasting a unity-gain bandwidth of 56 MHz, a slew rate of 160 V/µs, and ultra-low THD of 0.00003% at 1 kHz. Key features include a large signal bandwidth, negative rail input, power-down mode reducing current to 0.5 µA, and input voltage noise of 9.3 nV/√Hz at 100 kHz. Packaged options such as SOT-23, QFN, SOIC, VSSOP, and UQFN are available, accommodating a range of design requirements. The devices are ideal for battery-powered and portable applications, offering superior performance-to-power ratios for high-frequency amplifiers.

The Texas Instruments OPA863, OPA2863, and OPA4863 are low-power, voltage-feedback operational amplifiers designed to offer a unity-gain stable, rail-to-rail input and output with a 110-MHz bandwidth. These amplifiers are optimized for a broad power supply range from 2.7 V to 12.6 V, catering to a variety of portable and battery-powered applications. Key features include a quiescent current of 700-uA/ch (typical), a gain-bandwidth product of 50 MHZ, input voltage noise of 5.9-nV/VHz, and a slew rate of 105-V/us. The series also highlights specialized versions including the OPAx863A for high precision requirements, and all models integrate features like overload power limit and output short-circuit protection for ruggedized environments. The devices’ applicability spans across multiple domains including low-power SAR and ΔΣ ADC drivers, ADC reference buffers, photodiode transimpedance amplifiers, and more. The comprehensive array of packages available (including SOT-23, VSSOP, WQFN, and TSSOP options) ensures flexibility in hardware design, making these operational amplifiers from Texas Instruments suitable for high-performance, space-conscious, and power-sensitive electronic circuits.

The ADA4084-1, ADA4084-2, and ADA4084-4, manufactured by Analog Devices, Inc., are a series of low-power, rail-to-rail input/output operational amplifiers designed to operate from a single supply voltage ranging from +3 V to +30 V (or ±1.5 V to ±15 V). These amplifiers are characterized by their low noise performance (3.9 nV/√Hz at 1 kHz typical), low offset voltage (100 uV maximum for the SOIC package), and low power consumption (0.625 mA typical per amplifier at +15 V). With a gain bandwidth product of 15.9 MHz and a slew rate of 4.6 V/μs typical, these amplifiers are suitable for a broad range of applications, including battery-powered instrumentation, high-side and low-side sensing, power supply control and protection, and telecommunications among others. The ADA4084 series is available in various package options, ensuring flexibility and compatibility for different design requirements. Notably, the long-term drift and temperature hysteresis are meticulously engineered for consistent performance over time and across temperature variations, making these amplifiers robust choices for applications demanding precision and stability.

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 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

The PAM8610, manufactured by Power Analog Microelectronics, is a high-performance, 10W (per channel) stereo class-D audio amplifier featuring DC volume control. This component is designed to deliver low THD+N (0.1%), low EMI, and high efficiency (>90%), making it ideal for high-quality sound reproduction in a variety of applications such as flat monitor/LCD TVs, multi-media speaker systems, DVD players, game machines, boomboxes, and musical instruments. Operating off a 7V to 15V supply, the PAM8610 distinguishes itself with its 32-step DC volume control ranging from -75dB to 32dB, shutdown/mute/fade functions, and comprehensive protection against overcurrent, thermal, and short-circuit conditions. Its low quiescent current, pop noise suppression, and minimal external component requirement further enhance its appeal for compact and efficient audio solutions. The PAM8610 is available in a compact 40-pin QFN 6mm*6mm package, ensuring a small footprint for space-constrained applications. Compliance with RoHS standards underscores its environmental consideration. With its advanced features and high integration level, the PAM8610 offers a compelling option for designers seeking to incorporate robust audio amplification with fine-grained volume control in their electronic projects.

The NTMFS4C03N, manufactured by ON Semiconductor, is a high-performance, single N-Channel MOSFET designed for power applications. Encased in a compact SO-8FL package, this component offers a maximum drain-to-source voltage (VDSS) of 30V and a continuous drain current (ID) of up to 136A at 25°C. With an exceptionally low RDS(on) of 2.1 mΩ at VGS of 10V, it minimizes conduction losses, making it ideal for high-efficiency power management. Additionally, the MOSFET features low gate charge (QG) and capacitance, reducing driver losses and enhancing overall system efficiency. The device is Pb-Free, Halogen Free/BFR Free, and RoHS compliant, ensuring adherence to environmental standards. It also boasts a robust thermal performance with a junction-to-case thermal resistance (RθJC) of 1.95°C/W, making it suitable for applications requiring efficient heat dissipation. The NTMFS4C03N is available in tape and reel packaging options, accommodating various manufacturing needs.

The Atmel® | SMART SAM9260, manufactured by Atmel, is an ARM-based Embedded Microprocessor Unit (MPU), integrating the ARM926EJ-STM processor operating at 180 MHz. This MPU includes substantial on-chip memory and extensive peripherals, including an Ethernet MAC, USB Device and Host Ports, along with various standard interfaces such as USART, SPI, TWI, Timer Counters, and MultiMedia Card Interface. Architected on a 6-layer matrix delivering a maximum internal bandwidth of six 32-bit buses, it supports external 32-bit bus interfaces for SDRAM, static memories, CompactFlash, and SLC NAND Flash with ECC. The SAM9260 is available in 217-ball LFBGA and 208-pin PQFP packages. Key features include 8 Kbytes each of data and instruction cache, integrated MMU, two internal 4-Kbyte SRAMs, a 32-Kbyte ROM with bootloader, 22 Peripheral DMA channels, various power-on reset modes, two programmable clock signals, advanced interrupt controller, and multiple power management options for optimized performance and energy efficiency.

The OPA835 and OPA2835 from Texas Instruments are single and dual ultra-low-power, rail-to-rail output, negative-rail input, voltage-feedback (VFB) operational amplifiers designed for optimal performance in battery-powered and portable systems. Operating over a power supply range of 2.5 V to 5.5 V, these op amps consume only 250 µA per channel and offer a unity gain bandwidth of 56 MHz, making them industry leaders in performance-to-power ratio for rail-to-rail amplifiers. These components feature a quiescent current of 250 µA/ch (typical), with a power-down mode reducing current to 0.5 µA (typical), a slew rate of 160 V/µs, a rise time of 10 ns for a 2 V step, and a settling time of 55 ns to 0.1% for a 2 V step. Additional features include a signal-to-noise ratio (SNR) of 0.00015% (-116.4 dBc) at 1 kHz (1 VRMS), total harmonic distortion (THD) of 0.00003% (-130 dBc) at 1 kHz (1 VRMS), and a wide input voltage noise of 9.3 nV/√Hz at 100 kHz. The OPA835 and OPA2835 provide rail-to-rail output swing and input voltage range from -0.2 V to 3.9 V (5-V supply), supporting high-density, low-power signal conditioning applications with an operating temperature range from -40°C to +125°C. These components come in various package options, ensuring flexible integration into diverse electronic designs.

The Texas Instruments OPA835 and OPA2835 are ultra-low-power, rail-to-rail output, negative-rail input, voltage-feedback (VFB) operational amplifiers designed for operation across a wide power supply range of 2.5 V to 5.5 V with a single supply or +1.25 V to +2.75 V with a dual supply. These components are notable for their industry-leading performance-to-power ratio, which features a quiescent current of just 250 µA per channel and a unity gain bandwidth of 56 MHz. They are ideal for battery-powered, portable applications where power efficiency is critical, without compromising on high-frequency performance. The OPAx835 series brings the added benefit of a power-savings mode, reducing current consumption to less than 1.5 µA, making them an attractive choice for high-frequency amplifiers in battery-powered systems. Their compact package options, including SOT-23, SOIC, VSSOP, UQFN, and QFN, cater to space-constrained applications, providing a versatile solution for low-power signal conditioning, audio ADC input buffers, low-power SAR and ΔΣ ADC drivers, portable systems, low-power systems, high-density systems, and ultrasonic flow meters.