Is LCSC genuine? We don’t claim it sells fakes. But some alternatives listed there share TI’s part number and exact marking with weaker specs, test rejects can leak into the market, and cheap unmarked passives fail silently. The evidence, the passives myth, the real cost of cheap parts, and how to buy right.
AD8232 ECG trace buried in 50 Hz fuzz or a wandering baseline? Mains pickup, a laptop on its charger and a noisy 3.3 V supply are the usual causes. A 2-minute test, a safer battery-powered setup, a simple 50 Hz filter in code, and the electrode tips that matter.
PCM5102 DAC hissing, or whining whenever Wi-Fi is busy? Most of the time you are hearing the power supply: the DAC shares the ESP32’s 3.3 V with Wi-Fi bursts. A 2-minute battery test, a 3-step fix with clean wiring, jumper settings, and the other causes of noise.
analogRead values fluctuating while your sensor sits still? On Arduino the ADC measures against the noisy USB 5 V; on ESP32 Wi-Fi bursts and the ADC itself add more. A 2-minute AA-cell test, the AREF fix, ESP32 ADC settings, and when to use an ADS1115.
Your Arduino or ESP32 project works on battery but misbehaves on a phone charger or laptop USB? That’s power-supply noise. Find your symptom, run a 2-minute AA-cell test, and learn how to give sensitive parts a clean supply.
MAX4466 or MAX9814 microphone module hissing, spiking or triggering your LEDs in a silent room? The module amplifies noise on its 3.3 V supply up to 1000 times. A 2-minute AA-cell test, a 3-step fix, the other causes, and the engineering behind it.
NRF24L01 not working, “radio hardware not responding”, or losing packets? Most of the time the Arduino’s 3.3 V pin can’t keep up with the radio’s transmit bursts. A 2-minute AA-cell test, a 3-step fix, a checklist for the other causes, and the engineering behind it.
HX711, NAU7802, ADS1232 or other load cell readings jumping around? In many scale and bridge-sensor projects the cause is a noisy phone charger or USB supply. A quick AA-cell test, a 3-step fix and the full engineering analysis.
Three Samsung capacitors — same 10 µF, same X5R, same 25 V rating. At 12.5 V of DC bias the 1206 delivers 2.4× the capacitance of the 0603. Samsung’s own published curves, the physics behind them, and why the TrueVolt LN-7A2033 and PureRail C33 Nano use a 1206.
Application Note · AN-014 · Power Management The Inrush Current That Passes Every Bench Test and Blows the Fuse in