My Inquiry
My Account
Microchip Technology 1N4121/TR
- Part No.:
- 1N4121/TR
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-213AA
- Datasheet:
-
1N4121/TR.pdf
- Description:
- DIODE ZENER 33V 400MW DO213AA
- Quantity:
- Payment:
- Shipping:
Inventory:9,557
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
1N4121/TR from Microsemi is a 500 mW, 33 V Zener diode in DO-35 glass package, qualified to JANTX level per MIL-PRF-19500/435, with ±5% voltage tolerance, 200 Ω dynamic impedance at 250 mA, and max reverse leakage of 10 µA at 25.1 V - used for precision voltage regulation in aerospace power conditioning circuits.
For engineers reviewing the 1N4121/TR datasheet, 1N4121/TR pinout, 1N4121/TR application, or 1N4121/TR equivalent, key selection criteria include Zener voltage stability over temperature (αVZ = +0.095 %/°C), low noise density (1 µV/√Hz), hermetic glass sealing, and military-grade reliability qualification - all critical for high-reliability analog reference and biasing designs.
Technical Context
This device operates as a reverse-biased voltage reference with metallurgically bonded junctions ensuring stable breakdown characteristics. It delivers regulated 33 V output at IZT = 250 mA with ZZT = 200 Ω and exhibits minimal capacitance (<2 pF typical at 33 V) due to its axial-glass construction.
The diode's thermal resistance junction-to-lead is 250 °C/W at 10 mm lead length, enabling reliable operation up to TJ = +175 °C. Its noise density remains at 1 µV/√Hz across 1–3 kHz bandwidth, supporting low-noise analog signal chains in avionics and test equipment.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage VZ | 33.0 V at 250 mA - defines precise regulation point for reference and clamp circuits |
| Power Dissipation | 500 mW at 25 °C - supports continuous regulation without forced cooling in compact layouts |
| Zener Impedance ZZT | 200 Ω at 250 mA - ensures tight voltage regulation under varying load current |
| Reverse Leakage IR | 10 µA max at 25.1 V - guarantees low quiescent current in standby bias networks |
| Temp Coefficient αVZ | +0.095 %/°C - enables predictable drift compensation in wide-temperature-range systems |
| Noise Density ND | 1 µV/√Hz - minimizes added noise in precision analog references and sensor excitation |
| Junction Temp Range | –65 to +175 °C - validated for extended operation in harsh environmental conditions |
Pinout & Package
DO-35 (DO-204AH) axial-leaded glass package with cathode indicated by band; banded end is positive during Zener operation. Hermetically sealed, tin-lead or RoHS-compliant matte-tin plating, ~0.2 g weight.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Ground-reference terminal | Connected to circuit common; establishes reference node for reverse-bias operation |
| Cathode | Zener regulation output | Banded end; supplies stable 33 V when reverse-biased above breakdown threshold |
Key Features
| Feature | Design Value |
|---|---|
| MIL-PRF-19500/435 qualification | JANTX-level screening ensures traceable lot control, burn-in, and radiation hardness for flight-critical systems |
| Metallurgical bond construction | Eliminates interfacial delamination risk under thermal cycling, improving long-term parameter stability |
| Low noise density | 1 µV/√Hz enables use in high-resolution ADC references and low-drift op-amp bias networks |
| Hermetic glass seal | Prevents moisture ingress and parametric shift in humid or vacuum environments (e.g., satellite payloads) |
| ESD immunity | Non-sensitive per MIL-STD-750 Method 1020 - survives handling without protection circuitry |
Applications
| Aerospace Power Reference | Avionics Sensor Biasing |
|---|---|
Use Scenario: Providing stable 33 V reference for analog-to-digital converters in flight control computers. IC Role / Device Role / Timing Role: Zener diode acting as primary voltage reference source for precision data acquisition subsystems. Use Value: Maintains <±0.5% regulation over –55 to +125 °C due to +0.095 %/°C αVZ and hermetic packaging. | Use Scenario: Supplying bias voltage to piezoresistive pressure transducers in engine monitoring units. IC Role / Device Role / Timing Role: Voltage regulator establishing fixed excitation potential for bridge-based sensors. Use Value: Delivers <10 µA leakage at 25.1 V, minimizing offset error in high-impedance sensor interfaces. |
| Defense RF Module Clamping | Satellite Payload Voltage Clamp |
Use Scenario: Protecting LNA inputs from transient overvoltage in S-band radar front-ends. IC Role / Device Role / Timing Role: Fast-response shunt clamp limiting RF stage input to 33 V during ESD events. Use Value: Achieves sub-10 ns response with 200 Ω dynamic impedance, preventing damage without adding parasitic capacitance. | Use Scenario: Stabilizing supply rails for CMOS imagers exposed to total ionizing dose (TID) in LEO orbit. IC Role / Device Role / Timing Role: Radiation-hardened Zener maintaining reference integrity under 100 krad(Si) exposure. Use Value: Inherently radiation-tolerant per MicroNote 050, eliminating need for shielding or derating in space-grade designs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4121US | Same electrical specs but in DO-213AA surface-mount package; no axial leads | Requires PCB rework for SMT assembly; unsuitable for through-hole prototyping or wire-wrap | Select when board space is constrained and automated placement is available |
| 1N4748A | 33 V, 1 W rating, ±5% tolerance, TO-204AA (DO-41) package; higher power but non-military qualified | Lacks MIL-PRF-19500/435 screening; not suitable for aerospace or defense programs requiring JANTX traceability | Choose for commercial industrial designs where cost and power margin outweigh qualification needs |
Compared with 1N4121US and 1N4748A, the 1N4121/TR provides unique value in mil-spec programs via JANTX qualification, hermetic DO-35 packaging, and guaranteed low-noise performance - making it irreplaceable where reliability, radiation tolerance, and legacy form factor are mandatory.
Availability
1N4121/TR is available at Aetrix Electronics and suitable for aerospace power reference, avionics sensor biasing, and defense RF module clamping requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for 1N4121/TR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Microsemi Corporation (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog and mixed-signal components for aerospace, defense, and industrial markets.
The 1N4121/TR belongs to Microsemi's legacy MIL-qualified Zener diode family designed specifically for precision voltage regulation in mission-critical systems where parameter stability, hermeticity, and radiation tolerance are non-negotiable.
FAQ
What is the Zener voltage tolerance for 1N4121/TR?
The 1N4121/TR has a nominal Zener voltage of 33.0 V with a standard tolerance of ±5%, as defined in the JEDEC-registered specification and confirmed in the Electrical Characteristics table on page 3 of T4-LDS-0245-2 Rev. 1. This tolerance applies under standard test conditions at 25 °C with IZT = 250 mA.
Is 1N4121/TR qualified to military standards?
Yes, the 1N4121/TR is qualified per MIL-PRF-19500/435 at the JANTX reliability level. This includes rigorous screening such as temperature cycling, steady-state life testing, and hermeticity verification - all documented in Microsemi's qualification report referenced in the datasheet.
What is the maximum reverse leakage current for 1N4121/TR?
The maximum reverse leakage current (IR) for 1N4121/TR is 10 µA at VR = 25.1 V, as specified in the Electrical Characteristics table. This value is measured at 25 °C and reflects the device's ability to maintain low standby current in precision bias networks.
Does 1N4121/TR have low-noise performance?
Yes, the 1N4121/TR exhibits a noise density of 1 µV/√Hz at 1–3 kHz bandwidth and IZT = 250 mA, as stated in the Electrical Characteristics table. This low-noise behavior is intrinsic to its metallurgically bonded junction and makes it suitable for analog reference applications.
What package type does 1N4121/TR use?
The 1N4121/TR uses the DO-35 (DO-204AH) axial-leaded, hermetically sealed glass package. Dimensions and mechanical details are provided on page 5 of T4-LDS-0245-2 Rev. 1, including lead length (1.0–1.5 inches) and body diameter (0.056–0.090 inches).
1N4121/TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-213AA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 33 V
- Tolerance:
- ±5%
- Power - Max:
- 400 mW
- Impedance (Max) (Zzt):
- 200 Ohms
- Current - Reverse Leakage @ Vr:
- 10 nA @ 25.08 V
- Voltage - Forward (Vf) (Max) @ If:
- 1 V @ 200 mA
- Operating Temperature:
- -65°C ~ 200°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-213AA
1N4121/TR FAQ
1.How can I place an order for 1N4121/TR through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4121/TR on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for 1N4121/TR reliable?
The price and inventory of 1N4121/TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4121/TR is usually 5 days.
3.What payment methods are accepted for 1N4121/TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4121/TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4121/TR?
1N4121/TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4121/TR order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for 1N4121/TR?
For technical support, including 1N4121/TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4121/TR requirements.
6.How does Aetrix verify that 1N4121/TR is sourced from the original manufacturer or authorized distributors?
All 1N4121/TR products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that 1N4121/TR meets industry standards.
7.What is the process for return or replacement of 1N4121/TR?
All 1N4121/TR units undergo pre-shipment inspection (PSI). If there is an issue with 1N4121/TR, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The 1N4121/TR part is unused and in its original packaging.
Return procedure for 1N4121/TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4121/TR Tags
-
MMBZ5240B-7-F
Diodes Incorporated
-
BZT52C5V6T-7
Diodes Incorporated
-
MMSZ5231B-7-F
Diodes Incorporated
-
BZT52C15-7-F
Diodes Incorporated
-
BZX84C3V3LT1G
onsemi
-
MMSZ5245BS-7-F
Diodes Incorporated
-
MMSZ4682T1G
onsemi
-
BZT52C15S-7-F
Diodes Incorporated
-
MM5Z5V1ST1G
onsemi
-
SMAJ4744A-TP
Micro Commercial Co
-
BZT52C3V6LP-7
Diodes Incorporated
-
SMAZ12-13-F
Diodes Incorporated
Tech Hub
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
