LM2596 Step-Down Buck Converter (5V / 3A)
High-efficiency 150-kHz step-down switching regulator delivering a regulated 5V output at up to 3A continuous load from a 7V–40V DC supply with minimal external components.
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Interactive reference circuit schematics
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LM393 Precision Voltage Comparator with Hysteresis
Texas Instruments LM393 dual differential comparator in a non-inverting Schmitt trigger configuration with 48.5 mV positive feedback hysteresis, 2.5 V reference threshold, and open-collector output.
BSS138 Bidirectional I2C 3.3V to 5V Level Shifter
Bidirectional I2C bus voltage level translator interfacing 3.3V and 5V logic domains using two onsemi BSS138 N-channel MOSFETs with pull-up resistors and decoupled supplies.
L293D Dual H-Bridge DC Motor Driver
Complete dual bidirectional DC motor driver schematic using the Texas Instruments L293D quadruple half-H driver IC with independent PWM speed and direction control.
NE5532 Ultra-Low-Noise Inverting Microphone Preamplifier
Single-channel ultra-low-noise inverting audio preamplifier based on the Texas Instruments NE5532 op-amp, featuring +33.4 dB closed-loop gain, input DC blocking, and high-frequency phase compensation.
PC817 Optocoupler Galvanically Isolated Logic Interface
Sharp PC817 4-pin phototransistor optocoupler circuit providing 5000 Vrms galvanic isolation between field digital inputs and sensitive microcontroller logic with antiparallel reverse protection and passive collector pull-up.
ULN2003A 7-Channel Relay & Solenoid Inductive Load Driver
Texas Instruments ULN2003A 7-channel Darlington transistor sink driver circuit for 12V relays, solenoids, and stepper coils with internal inductive flyback clamp diodes and decoupling.
IRLZ44N Logic-Level N-Channel MOSFET Low-Side DC Switch
Discrete 12V/24V low-side DC switch circuit driving high-current inductive and resistive loads with an Infineon IRLZ44NPbF logic-level MOSFET from 3.3V or 5V MCU logic.
2N2222 / 2N2222A NPN BJT Relay Driver with 1N4007 Flyback Clamping Diode
Discrete NPN bipolar junction transistor low-side relay driver circuit with 1N4007 flyback suppression diode, base saturation drive, and supply decoupling for 3.3V/5V MCU control.