BZX84-C18,215

BZX84-C18 is a small-signal Zener diode (0.5 W) in a SOT-23 package, with a nominal Zener voltage of 18 V. The “C” suffix typically indicates about ±5% tolerance (tighter tolerances exist with other suffixes).
Key points
- Voltage: Vz ≈ 18 V (tolerance ~±5% per vendor)
- Power: ~0.5 W
- Package: SOT-23 (two terminals used for the Zener function)
- Test current: Iz commonly around 5 mA for Vz specification
- Uses: simple voltage regulation, references, voltage clamping/protection in low-power circuits
- Leakage and impedance: reverse leakage is small; Zzt increases at low currents
Related parts
- BZX84-C21 (21 V) is the same family with a higher Zener voltage. Other voltages exist in the BZX84-Cxx series.
Note: For exact values (Vz range, Iz, Zzt, packaging), consult the specific manufacturer’s datasheet. If you meant BZX84-C21 or another variant, I can compare them.

Equivalent parts (18 V, 0.5 W Zener in SOT-23):
- BZX84-C18 (Nexperia/Philips)
- BZX84C18 (Vishay)
- BZX84C18 (Diodes Inc)
- BZX84C18 (On Semiconductor)
- MMBZ5236B (18 V, SOT-23; cross-ref across manufacturers)

Concise features of BZX84-C18 (18 V Zener):
- Zener voltage: 18 V, tolerance ±5% (C)
- Power rating: 0.5 W (Ptot), at Ta = 25°C
- Package: Small SMD (BZX84 series)
- Reverse breakdown voltage: ~18 V
- Test current (Vz measurement): IZT ≈ 5 mA
- Operating temp range: roughly -55°C to +125°C
- RoHS compliant
- Applications: voltage regulation, reference, over-voltage protection
Note: Dates/lot codes (e.g., 215) are manufacturing identifiers and do not affect electrical characteristics.

- Pin count: 3 pins (SOT-23 package)
- Function: 18 V Zener diode (voltage reference/regulator/clamp)
- Pinout: pins 1 and 3 are the cathode, pin 2 is the anode
- Note: “215” is a date/lot code.

Manufacturer: Vishay Intertechnology (Vishay).
What kind of company: A multinational electronics components company that designs and manufactures discrete semiconductors and passive components (headquartered in Malvern, Pennsylvania, USA).

BZX84-C18 (18 V) and BZX84-C21 (21 V) are small-signal Zener diodes (500 mW, SOT‑23). Common applications:
- Simple shunt regulators and voltage references in low‑power circuits
- Reference voltages for ADC/DAC and op-amp bias networks
- Overvoltage/transient protection on power rails and I/O lines
- Signal clipping and waveform shaping in analog/digital interfaces
- Input protection for microcontrollers and regulators
- Noise suppression and stabilizing elements in regulator start‑up networks
Note: use with appropriate series resistor to set current within ratings.

SOT-23 (SOT-23-3) surface-mount package.