Loads when you scroll to it. Unloads after 5 minutes in the background.

Symbol & Footprint

Schematic Symbol

Open full view ↗
Loads when you scroll to it. Unloads after 5 minutes in the background.

PCB Footprint

Open full view ↗
Loads when you scroll to it. Unloads after 5 minutes in the background.
Loads when you scroll to it. Unloads after 5 minutes in the background.
Download PDF
Contents

README

markdown

MMBZ5254B

Changjing · Zener Diodes · SOT-23

MMBZ5254B from Changjing, in a SOT-23. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 A passive Zener anode, shown on the page 1 symbol as the diode input; the MMBZ5254B has a 27V nominal Zener voltage (25.65V to 28.35V) at IZT = 5.0mA.
2 NC unconnected Pin 2 is drawn as an isolated terminal with no internal connection in the page 1 symbol.
3 K passive Zener cathode, the bar side of the diode symbol; maximum leakage is 0.1µA at VR = 21V and power dissipation is limited to 300mW.

Key specifications

Parameter Value
Manufacturer Changjing
Package SOT-23
Category Diodes
Pins 3

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter Symbol Min Typ Max Unit Conditions Page
Zener Voltage VZ 25.65 27 28.35 V @ IZT = 5.0 mA 2
Maximum Zener Impedance ZZT 41 Ω @ IZT = 5.0 mA, f = 1kHz 2
Maximum Zener Impedance (knee) ZZK 600 Ω @ IZK = 0.25mA 2
Maximum Reverse Leakage Current IR 0.1 µA @ VR = 21 V 2
Forward Voltage VF 0.9 V IF = 10mA 1
Power Dissipation PD 300 mW Ta = 25℃ 1
Operation Junction and Storage Temperature Range TJ,TSTG -55 150 ℃ 1
Thermal Resistance Junction to Ambient RθJA 417 ℃/W 1
Zener Test Current IZT 5 mA Test current for VZ and ZZT 2
Nominal Zener Voltage VZ nom 27 V @ IZT 2

CAD (KiCad official)

  • Symbol: MMBZ5254B
  • Footprint: Package_TO_SOT_SMD:SOT-23
  • 3D model: SOT-23 (KiCad packages3D, STEP)
  • 3D model files: mmbz5254b-etched.step / mmbz5254b-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); mmbz5254b.step / mmbz5254b.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Changjing datasheet (5 pp, sha256 eab0dbad2cbe9e7d, retrieved 2026-10-22, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-sonnet-5-5 (text+vision), consensus claude-opus-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF