Passives
Resistors, capacitors, diodes and transistors in kit quantities — the parts every project assumes you already have, sold in the volumes that make that assumption true.
E12 resistor kits, ceramic and electrolytic capacitor sets, 1N4148/1N4007 diodes, TIP120 Darlingtons, IRLZ44N MOSFETs and 100F supercapacitors — bench stock in kit quantities.
- Diodes split by job: 1N4148 for fast small-signal switching, 1N4001/1N4007 for rectifying up to 1A, Zeners for voltage clamping, and Adafruit's LM73100 ideal-diode breakout when a 0.7V forward drop costs too much.
- For switching loads: PN2222 NPNs handle small currents, TIP120 Darlingtons take motor-class loads at the cost of base-drive losses, and the IRLZ44N logic-level MOSFET switches hard from a 3.3V GPIO.
- Kits beat singles: E12 resistor sets (10Ω–1MΩ, 610 pcs), ceramic 10pF–220nF and electrolytic 1µF–1000µF capacitor sets cover virtually every breadboard value you will hit.
- Outliers worth knowing: 100F/2.7V supercapacitors for ride-through power, and the KSD301 bimetal thermal cutoff that opens mechanically at a set temperature with no controller involved.
