Specifications
| Type | Description |
|---|---|
| Part Number | 1N4728A |
| Manufacturer | Vishay |
| Product Type | LDO Regulator |
| Category | Power Management |
| Package / Case | DO-41 (DO-204AL) |
| Nominal Zener Voltage | 3.3 V; at IZT1=76 mA, Tamb=25°C |
| Zener Voltage Tolerance | ±5 % |
| Reverse Leakage Current | 100 µA max; VR=1 V |
| Dynamic Resistance ZZT | 10 Ω max; at IZT1=76 mA |
| Dynamic Resistance ZZK | 400 Ω max; at IZT2=1 mA |
| Power Dissipation | 1300 mW; Tamb=25°C |
| Regulator Current IZM | 276 mA max |
| Forward Voltage | 1.2 V max; IF=200 mA |
| Junction Temperature | 175°C |
| Moisture Sensitivity Level | MSL level 1 |
| Datasheet Status | request_only |
Product Overview
The Vishay 1N4728A is a single silicon planar power Zener diode for voltage stabilization in the Power_Management category. Its nominal Zener voltage is 3.3 V with a standard ±5 % tolerance, measured at IZT1 = 76 mA under thermal equilibrium at Tamb = 25°C. The datasheet also defines the Zener current relationship as IZ = PV/VZ for absolute maximum ratings with tp = 10 ms.
Electrical parameters include 10 Ω maximum dynamic resistance ZZT at 1 kHz and IZT1 = 76 mA, plus 400 Ω maximum ZZK at 1 kHz and IZT2 = 1 mA. Reverse leakage is specified as 100 µA maximum at VR = 1 V, and forward voltage is 1.2 V maximum at IF = 200 mA.
The device uses a DO-41 (DO-204AL) package with 4.1 mm maximum body length, 2.6 mm maximum body diameter, 26 mm minimum lead length on each side, and a cathode identification band. Package details include approximately 310 mg weight, MSL level 1 per J-STD-020, UL 94 V-0 molding compound flammability rating, and 260°C maximum soldering peak temperature.
Key Features
- 3.3 V nominal Zener voltage at IZT1
- Standard ±5 % Zener voltage tolerance
- 10 Ω maximum dynamic resistance
- 400 Ω maximum ZZK at 1 mA
- 100 µA maximum reverse leakage at 1 V
- 1300 mW power dissipation
- 276 mA maximum regulator current
- Single silicon planar power Zener diode
- DO-41 package with cathode band
- MSL level 1 per J-STD-020
Typical Applications
- Voltage stabilization
- 3.3 V Zener regulation
- Single-diode stabilization circuits
- DO-41 through-hole assemblies
- Power management voltage reference use
Procurement Notes
When requesting a quote for 1N4728A, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.
If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.
For power IC and power device sourcing, voltage rating, current rating, power dissipation, package thermal performance, protection features, qualification grade and application conditions should be reviewed before approval.
FAQ
What is the nominal Zener voltage of 1N4728A?
The 1N4728A has a nominal Zener voltage of 3.3 V at IZT1 under thermal equilibrium at Tamb=25°C.
What package does the Vishay 1N4728A use?
The device uses a DO-41 (DO-204AL) package with cathode band, 4.1 mm max body length, 2.6 mm max body diameter.
What is the power dissipation rating?
Power dissipation is 1300 mW at 25°C with leads 4 mm from case.
What reverse leakage limit is specified?
Reverse leakage current is 100 µA maximum at VR=1V, Tamb=25°C.
Technical Review & Sourcing Note
Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: July 19, 2026.
This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.