Low-Noise High-Gain Discrete MOSFET Audio Amplifier Design

Internet Radio (Mono for now) using MAX98357A Class D Amplifier.

Radxa Zero 100mm Circular Audio Board: 4-Channel Mic Array & 3W Class-D Amplifier with USB-C Power

Radxa Zero 100mm Circular Audio Board: 4-Channel Mic Array & 3W Class-D Amplifier with USB-C Power

Circuit Overview The circuit you're describing is a digital counter that uses an LDR (Light-Dependent Resistor) and a transistor to detect wheel rotations. The counter's output is then displayed on a seven-segment LED display. Here's a breakdown of the components and their roles: 1. Wheel Rotation Detection (LDR and Transistor) * LDR: The LDR acts as a sensor to detect changes in light intensity. You can mount it on the wheel' or near it, with a reflective or non-reflective surface attached to the wheel. As the wheel rotates, the LDR will be exposed to alternating light and dark conditions, causing its resistance to change. * Transistor: The transistor (e.g., a 2N2222 NPN BJT) is used as a switch or amplifier. The changing resistance of the LDR is used to control the base current of the transistor. When the LDR's resistance drops (more light), the transistor turns on, and when the resistance increases (less light), the transistor turns off. This converts the analog change in light into a digital ON/OFF signal (a pulse). 2. Counter (7490) * 7490 IC: This is a decade counter, meaning it can count from 0 to 9. The output of the transistor (the pulses) is fed into the clock input of the 7490. Each pulse represents one rotation of the wheel, and the 7490 increments its count accordingly. The 7490 has four outputs (Q0, Q1, Q2, Q3) that represent the BCD (Binary-Coded Decimal) equivalent of the count. 3. BCD to Seven-Segment Decoder (7446) * 7446 IC: The 7446 is a BCD-to-seven-segment decoder/driver. Its job is to take the 4-bit BCD output from the 7490 and convert it into a signal that can drive a seven-segment LED display. It has seven outputs (a, b, c, d, e, f, g), each corresponding to a segment of the LED display. 4. Seven-Segment LED Display * Seven-Segment Display: This display is used to show the count. The 7446's outputs are connected to the corresponding segments of the display. 5. Power Supply and Other Components * Power Supply: A regulated DC power supply (e.g., 5V) is needed to power all the ICs and components. * Resistors: Resistors are used for current limiting (e.g., for the LDR and the LED display) and biasing the transistor. * Capacitors: A capacitor might be used for debouncing the signal from the transistor to prevent multiple counts for a single rotation. Conceptual Connections Here is a step-by-step breakdown of how the components would be connected: * LDR and Transistor: * The LDR and a current-limiting resistor are connected in series across the power supply. * The junction between the LDR and the resistor is connected to the base of the NPN transistor. * The emitter of the transistor is connected to ground. * The collector of the transistor, with a pull-up resistor, becomes the output for the pulse signal. * Transistor to 7490: * The output from the transistor's collector is connected to the clock input of the 7490 IC. * The 7490's reset pins (MR and MS) should be connected to ground for normal counting operation. * 7490 to 7446: * The BCD outputs of the 7490 (Q0, Q1, Q2, Q3) are connected to the BCD inputs of the 7446 (A, B, C, D). * 7446 to Seven-Segment Display: * The outputs of the 7446 (a, b, c, d, e, f, g) are connected to the corresponding segments of the seven-segment display. * Crucially, you need to use current-limiting resistors (e.g., 330Ω) in series with each segment to protect the LEDs from high current. * The common terminal of the seven-segment display is connected to the power supply (for a common anode display) or ground (for a common cathode display). This setup creates a chain reaction: wheel rotation changes light, which changes LDR resistance, which turns the transistor on/off, generating a pulse. This pulse increments the 7490, and the 7490's output is decoded by the 7446, which then displays the count on the seven-segment LED.

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

Raspberrypi Pico-based sampler, sequencer + drum machine w/ an embedded speaker, Adafruit I2S amplifier and momentary step switches, evoking the tr808 synthesizer ⁠

Adafruit MAX31865 RTD PT100 or PT1000 Amplifier #MAX31865 #smartHome #sensor #temperatureSensor #temperature #Amplifier #PT100 #PT1000 #referenceDesign #template

This project is an innovative audio amplifier design focused on delivering high-quality sound and performance for commercial applications. The design features a robust 220V AC input that undergoes careful transformation, rectification, and regulation to provide a stable power supply. Central to the project is an audio amplifier circuit engineered to deliver a reliable 20W output, ensuring optimal sound clarity and efficiency. To enhance usability and connectivity, the design incorporates premium audio connectors for seamless input and output integration. This project prioritizes safety, efficiency, and scalability, positioning it as an ideal solution for fairs, events, and other commercial audio applications. #AudioAmplifier #220VAC #20WOutput #AudioConnectors #CommercialAudio #HighFidelitySound

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

DIP825W47P254L1917H533Q14 PDIP-14 Texas Instruments LM324N 4-Channel industry standard operational amplifier 14-PDIP 0 to 70 https://pricing.snapeda.com/search/part/LM324N/?ref=eda Texas Instruments None In Stock Aliases: undefined

DIP825W47P254L1917H533Q14 PDIP-14 Texas Instruments LM324N 4-Channel industry standard operational amplifier 14-PDIP 0 to 70 https://pricing.snapeda.com/search/part/LM324N/?ref=eda Texas Instruments None In Stock Aliases: undefined

[Replace with project description] #template #templates #speaker #amplifier #projects

This is a Class-D amplifier design project based on the PAM8302A IC #Class-D #amplifier #PAM8302A

Glucose meter is a medical device that determines the approximate concentration of glucose in the blood. A strip containing chemicals that react with glucose in the drop of blood is used for each measurement. Op Amp Circuit description: LMC6484 IC_D is an integrator circuit. LMC6484 IC_A and IC_C are configured as unity gain buffer amplifiers. LMC6484 IC1B is configured as a trans impedance amplifier. Arduino is used for processing of the measured glucose level. The Arduino use the built in ADC module for analog to digital conversion. Further, the Arduino helps to detect the strip also.

Crown XLS1000 amplifier schematic

This project is a low-noise amplifier (LNA) circuit. It primarily uses a BFU520YX transistor as the active component. BNC connectors are used for signal input and output. The circuit is designed for high-frequency signals. #project #Template #projectTemplate #LNA #RF #BFU520YX

amplifier

- ESP32 DevKitC V4 (microcontroller) - 2x BME280 sensors (temperature, humidity, pressure) - 8ch relay board with 12VDC relays (NO/NC SPDT) - 12VDC power supply - USB connectivity - Various components (resistors, caps, opto couplers, op-amps, motor drivers, multiplexers) - 2x SPDT relay boards (for fan fail-safe) - 4x 2ch bidirectional level controllers (3.3V to 5V) - ESP32 GPIO 21 (SCL) to BME280's SCL - ESP32 GPIO 22 (SDA) to BME280's SDA - ESP32 GPIO 5 (digital output) to 8ch relay board input - ESP32 GPIO 25 (PWM output) -> Fan PWM (0-255 value) - ESP32 GPIO 26 (PWM output) -> Light PWM (0-255 value) - ESP32 GPIO 34 (analog input) -> Tachometer input (0-4095 value, 12-bit ADC) - Add a 5V voltage regulator (e.g., 78L05) to power the ESP32 and other 5V components - Add a 3.3V voltage regulator (e.g., 78L03) to power the BME280 sensors and other 3.3V components - Include decoupling capacitors (e.g., 10uF and 100nF) to filter the power supply lines - Ensure proper grounding and shielding to minimize noise and interference -- Power supply: - VCC=12VD Available, to be used for LM358P - 5V voltage regulator (78L05) - VCC=5V, GND=0V - 3.3V voltage regulator (78L03) - VCC=3.3V, GND=0V - 3.3V voltage regulator (78L03) - VCC=3.3V, GND=0V - Fan PWM boost: - Input (3.3V PWM): 0-3.3V, frequency=20kHz - Output (5V PWM): 0-5V, frequency=20kHz - LM358P op-amp (unity gain buffer) - VCC=5V, GND=0V - R1=1kΩ, R2=1kΩ, R3=1kΩ, R4=1kΩ - C1=10uF (50V), D1=1N4007 - 0-10V signal conditioning: - Input (3.3V PWM): 0-3.3V, frequency=13kHz - Output (0-10V): 0-10V, frequency=13kHz - LM358P op-amp (non-inverting amplifier) - VCC=5V, GND=0V - R5=2kΩ, R6=1kΩ, R7=2kΩ, R8=1kΩ, R9=1kΩ, R10=2kΩ - C2=10uF (50V), R11=10kΩ (1%) ------------------------------------ Fan PWM Boost (3.3V to 5V): 1. ESP32 GPIO 25 (PWM output) -> R1 (1kΩ) -> VCC (3.3V) 2. ESP32 GPIO 25 (PWM output) -> R2 (1kΩ) -> Vin (LM358P) 3. LM358P (Voltage Follower): - VCC (5

Amplifier IC 1-Channel (Mono) Class AB 15-Multiwatt #Amplifier #Audio #commonpartslibrary

The 2N7002DW, manufactured by iSion, is an N-channel enhancement mode field-effect transistor (FET) designed for high-speed pulse amplifier and drive applications. It is fabricated using the N-channel DMOS process and comes in a compact SOT-363 package. The component offers robust ESD protection compliant with MIL-STD 833, +2.5KV contact discharge. Key features include a drain-source voltage (VDSS) of 60V, a gate-source voltage (VGSS) of +20V, and a continuous drain current (ID) of 300mA, with a pulsed drain current (IDM) of 800mA. The device has a maximum power dissipation (PD) of 350mW and operates within a junction temperature range of -55°C to +150°C. Additionally, it exhibits a low static drain-source on-resistance (RDS(ON)) of 2.0Ω at VGS = 10V and ID = 300mA, making it suitable for efficient switching applications. The thermal resistance from junction to ambient (RθJA) is rated at 500°C/W, ensuring reliable performance in various thermal conditions.

DIP825W47P254L1917H533Q14 PDIP-14 Texas Instruments LM324N 4-Channel industry standard operational amplifier 14-PDIP 0 to 70 https://pricing.snapeda.com/search/part/LM324N/?ref=eda Texas Instruments None In Stock Aliases: undefined

DIP825W47P254L1917H533Q14 PDIP-14 Texas Instruments LM324N 4-Channel industry standard operational amplifier 14-PDIP 0 to 70 https://pricing.snapeda.com/search/part/LM324N/?ref=eda Texas Instruments None In Stock Aliases: undefined

DIP825W47P254L1917H533Q14 PDIP-14 Texas Instruments LM324N 4-Channel industry standard operational amplifier 14-PDIP 0 to 70 https://pricing.snapeda.com/search/part/LM324N/?ref=eda Texas Instruments None In Stock Aliases: undefined

DIP825W47P254L1917H533Q14 PDIP-14 Texas Instruments LM324N 4-Channel industry standard operational amplifier 14-PDIP 0 to 70 https://pricing.snapeda.com/search/part/LM324N/?ref=eda Texas Instruments None In Stock Aliases: undefined