This project is a BLE door and window sensor design that uses a U-blox BMD-330-A-R for BLE communication, a reed switch as a sensor, a multi-color LED for status display, and is powered by VBAT. There's also a programming interface and reset switch included. #WiFi #BLE #MCU #ReferenceDesign #project #referenceDesign #simple-embedded #ublox #template #reference-design

This project is a WiFi RF-ID Lock, which uses a Espressif ESP-8684 microcontroller for WiFi connectivity and a Handson Technology RC522 for RF-ID functionality. It also includes an OLED display and user control via a switch. A step-up power converter ensures consistent 3.3V power. #WiFi #MCU #ReferenceDesign #project #ESP8684 #lock #OLED #referenceDesign #simple-embedded #espressif #template #reference-design

A power switch using a push button. It turns on with a single press and only turns off when you hold the button down. This could be used to get functionality similar to most laptops where a single press when on will initiate a "soft" shutdown but you can force a "hard" shutdown by holding it down.

This circuit drives 10 LEDs making them flash to the rhythm of the music (using a TIP31C transistor to act as a voltage-controlled switch) Credit: https://www.youtube.com/watch?v=3qZ3uA8hDmE

BLE remote control board. Based on SoC ESP32-C3-MINI-1 that allows you to program it as HID volume multichannel control, you can switch channels with the user button, or use it as arrow keys.

CheckIt is a daily habit tool. When you complete a habit, flip a switch, then an LED lights up. Future work will include wiring the 24pin FPC port to the Pico which causes an e-paper screen to display a message when a switch is flipped. This PCB runs using a Raspberry Pi Pico and has plans to be battery powered similar to a digital alarm clock.

This circuit drives 10 LEDs making them flash to the rhythm of the music (using a TIP31C transistor to act as a voltage-controlled switch) Credit: https://www.youtube.com/watch?v=3qZ3uA8hDmE

Simple UPDI programmer for tinyAVR, megaAVR and AVR-Dx microcontrollers with voltage selection switch (5V and 3.3V).

BLE remote control board. Based on SoC ESP32-C3-MINI-1 that allows you to program it as HID volume multichannel control, you can switch channels with the user button, or use it as arrow keys.

High-level recreation of the ThirstIQ Cap wiring diagram using an ESP32-WROOM-32 with AMS1117-3.3 regulated battery input, inline ON/OFF switch, four touch input headers on IO32/IO33/IO25/IO26, shared I2C OLED and RTC on IO21/IO22, UART debug/programming header on TXD0/RXD0, BOOT and RESET pushbuttons on IO0 and EN, buzzer on IO4, common 3V3/GND distribution, and PCB preparation for a 160 mm x 100 mm 4-layer layout. Layout intent includes clean 3.3 V power distribution, local decoupling for regulator and ESP32, accessible external headers/buttons, short clean BOOT/EN traces, shared I2C routing, touch-signal separation from noisy power and buzzer traces, and ESP32 antenna keepout.

Nice — you can do a clean pulse + latch using a single quad Schmitt-NAND chip: 74HC132 (or 74LVC132 for 3.3 V systems). The HC132 contains four 2-input NAND gates with Schmitt inputs so you can both clean a noisy SYN480R DATA line and build an SR latch (NAND SR is active-LOW) inside one package. Only a few passives and a driver transistor are needed. Below is a ready-to-build recipe (parts, wiring, explanation, tuning tips, and an ASCII schematic) — no extra logic ICs required. Parts (per latch) 1 × 74HC132 (quad 2-input NAND with Schmitt inputs). If your system is 3.3 V use 74LVC132 / 74HC132 rated for 3.3 V. Rin = 47 kΩ (input series) Cfilter = 10 nF (input RC to ground) — tweak for debounce/clean time Rpulldown = 100 kΩ (pull-down at input node, optional) Rpullup = 100 kΩ (pull-up for active-LOW R input so reset is idle HIGH) Rbase = 10 kΩ, Q = 2N2222 (NPN) or small N-MOSFET (2N7002) to drive your load Diode for relay flyback (1N4001) if you drive a coil Optional small cap 0.1 µF decoupling at VCC of IC Concept / how it works (short) Use Gate1 (G1) of 74HC132 as a Schmitt inverter by tying its two inputs together and feeding a small RC filter from SYN480R.DATA. This removes HF noise and provides a clean logic transition. Because it's a NAND with tied inputs its function becomes an inverter with Schmitt behavior. Use G2 & G3 as the cross-coupled NAND pair forming an SR latch (active-LOW inputs S̄ and R̄). A low on S̄ sets Q = HIGH. A low on R̄ resets Q = LOW. Wire the cleaned/inverted output of G1 to S̄. A valid received pulse (DATA high) produces a clean LOW on S̄ (because G1 inverts), setting the latch reliably even if the pulse is brief. R̄ is your reset input (pushbutton, HT12D VT, MCU line, etc.) — idle pulled HIGH. Q drives an NPN/MOSFET to switch your load (relay, LED, etc.). Recommended wiring (pin mapping, assume one chip; use datasheet pin numbers) I’ll refer to the 4 gates as G1, G2, G3, G4. Use G4 optionally for additional conditioning or to build a toggler later. SYN480R.DATA --- Rin (47k) ---+--- Node A ---||--- Cfilter (10nF) --- GND | Rpulldown (100k) --- GND (optional, keeps node low) Node A -> both inputs of G1 (tie inputs A and B of Gate1 together) G1 output -> S̄ (S_bar) (input1 of Gate2) Gate2 (G2): inputs = S̄ and Q̄ -> output = Q Gate3 (G3): inputs = R̄ and Q -> output = Q̄ R̄ --- Rpullup (100k) --- VCC (reset is idle HIGH; pull low to reset) (optional) R̄ can be wired to a reset pushbutton to GND or to an MCU pin Q -> Rbase (10k) -> base of 2N2222 (emitter GND; collector to one side of relay coil) Other side of relay coil -> +V (appropriate coil voltage) Diode across coil If you prefer MOSFET low side switching: Q -> gate resistor 100Ω -> gate of 2N7002 2N7002 source -> GND ; drain -> relay coil low side

Create a schematic diagram of an electric fence controller using the NE556 dual timer IC. The circuit must include all components with clear electronic symbols (resistors, capacitors, transistors, diode, relay) connected by lines as in a real circuit diagram. Specifications: 1. Power supply: - Vcc = +12V connected to pin 14 of the NE556. - Pin 1 of the NE556 to ground. 2. Timer A (active 10 seconds): - Pin 2 (Trigger A) receives a pulse from transistor Q2 (contact detector). - Pin 6 (Threshold A) connected to Pin 7 (Discharge A). - R1 = 1 MΩ between Pin 7 and +12V. - C1 = 10 µF between Pin 6 and ground. - Pin 3 (Out A) goes through a 4.7 kΩ resistor to the base of Q1 (BC547 NPN transistor). - Pin 3 also connected via a 100 nF capacitor to Pin 13 (Trigger B of Timer B). 3. Timer B (rest 10 seconds): - Pin 9 (Discharge B) and Pin 8 (Threshold B) connected together. - R2 = 1 MΩ between Pin 9 and +12V. - C2 = 10 µF between Pin 8 and ground. - Pin 12 (Out B) can be optionally used to block retrigger of Timer A. 4. Relay driver stage: - Q1 = BC547 NPN transistor. - Base connected through 4.7 kΩ resistor to Pin 3 (Out A). - Emitter to ground. - Collector connected to one side of the relay coil. - Other side of relay coil connected to +12V. - A diode 1N4007 placed in parallel with the relay coil (cathode to +12V, anode to collector of Q1). - Relay contacts switch the +12V supply to the electric fence energizer. 5. Contact detector: - Shunt resistor ≈0.1 Ω placed in series with the fence output. - Q2 = BC547 NPN transistor, base connected to the shunt, emitter to ground, collector to Pin 2 (Trigger A). - When current flows through the shunt, Q2 provides a trigger pulse to Timer A. Please draw the schematic in a standard style with components connected by straight lines, not in block diagrams. Show clear pin numbers of the NE556 and all external components.

This project is a WiFi RF-ID Lock, which uses a Espressif ESP-8684 microcontroller for WiFi connectivity and a Handson Technology RC522 for RF-ID functionality. It also includes an OLED display and user control via a switch. A step-up power converter ensures consistent 3.3V power. #WiFi #MCU #ReferenceDesign #project #ESP8684 #lock #OLED #referenceDesign #simple-embedded #espressif #template #reference-design

Flatbox styled hand solderable PCB featuring a side passthrough, oled screen, focus mode and DP/LS/RS switch

This circuit drives 10 LEDs making them flash to the rhythm of the music (using a TIP31C transistor to act as a voltage-controlled switch) Credit: https://www.youtube.com/watch?v=3qZ3uA8hDmE

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.

This is an Alexa Controlled Switch.

A switch that only has a single input and can connect to and switch between 2 outputs.

An adapter board for connecting a Switch thumbstick to a Svalboard's Azo port. E.g.: https://www.aliexpress.com/item/1005006610796603.html?spm=a2g0o.order_list.order_list_main.190.22561802UNXosq

A switch that only has a single input and can connect only to one output.

A switch that only has a single input and can connect only to one output.

UK Smart Wall Switch Back Board: 802.3af PoE-powered 65x65mm relay and energy-monitoring back board with RJ45, isolated 5V/3.3V rails, W5500 Ethernet, BL0942 metering, touch ICs, and 12-pin pogo interface.

Rebuilt two-layer PIC16F628A DTMF relay audio switch with 12 V input, MT8870 decoding, PIC16F628A control, relay driver, and audio switching path.

Turn an LED ON and OFF with a Switch

This project is a WiFi Gesture Light Switch controlled by an ESP32 microcontroller. It leverages APDS-9960 and CH340C ICs for gesture recognition and USB communication respectively. Essential components include diodes for voltage protection, LEDs for status indication, and an AMS1117 voltage regulator to ensure a stable power supply. Connectors like USB Type-C are used for power and data transfers. #referenceDesign #project #ESP32 #ESP32WROOM #RF #WIFI #MCU #thermostat #referenceDesign #edge-computing #edgeComputing #espressif #template #reference-design