My Inquiry
My Account
Microchip Technology 1N4120
- Part No.:
- 1N4120
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- -
- Datasheet:
-
1N4120.pdf
- Description:
- DIODE ZENER
- Quantity:
- Payment:
- Shipping:
Inventory:8,957
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
1N4120 from Microsemi is a 500 mW, 30.0 V Zener diode in DO-35 glass package, qualified to JANTXV level per MIL-PRF-19500/435, with 5% voltage tolerance, 200 Ω dynamic impedance at 250 mA test current, and maximum reverse leakage of 0.01 µA at 22.8 V. It serves as a precision voltage reference in military-grade power regulation and analog signal conditioning circuits.
For engineers reviewing the 1N4120 datasheet, 1N4120 pinout, 1N4120 application, or 1N4120 equivalent, this page delivers verified electrical parameters, thermal derating behavior, noise density (1 µV/√Hz), temperature coefficient (+0.095 %/°C), and direct alternatives for high-reliability analog design and aerospace power supply validation.
Technical Context
The 1N4120 operates in reverse breakdown with metallurgically bonded junctions, enabling stable regulation across -65°C to +175°C ambient. Its 250 mA Zener test current and 200 Ω dynamic impedance ensure low-voltage drift under load variation, while its 1 µV/√Hz noise density supports low-noise reference applications below 3 kHz bandwidth.
Thermal resistance is 250°C/W junction-to-lead (at 10 mm lead length) and 300°C/W junction-to-ambient on FR4 board, requiring linear derating from 500 mW at 25°C to zero at 175°C. The cathode band polarity marking and hermetically sealed DO-35 package support high-reliability mounting in harsh environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage VZ | 30.0 V @ 250 mA - precise regulation point for mid-range voltage references |
| Power Dissipation | 500 mW @ 25°C - supports continuous operation in compact axial-leaded layouts |
| Dynamic Impedance ZZT | 200 Ω @ 250 mA - ensures <±0.5 V output shift over 10–100 mA load current range |
| Reverse Leakage IR | 0.01 µA @ 22.8 V - enables ultra-low standby current in battery-backed circuits |
| Temp. Coefficient αVZ | +0.095 %/°C - predictable positive drift simplifies compensation in wide-temp designs |
| Noise Density ND | 1 µV/√Hz @ 250 mA - meets low-noise requirements for precision ADC references |
| Junction Temp. Range | -65°C to +175°C - certified for extended operation in aerospace and downhole systems |
Pinout & Package
DO-35 (DO-204AH) glass axial-leaded package: hermetically sealed, tin-lead or RoHS-compliant matte-tin plating, cathode indicated by black band. Weight ≈ 0.2 g. Dimensions: body diameter 1.42–2.29 mm, body length 3.56–5.08 mm, lead length 25.4–38.1 mm.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Zener cathode reference ground | Connected to circuit ground or lower-potential node during regulation |
| Cathode | Zener regulation output / reverse-biased breakdown terminal | Banded end; supplies stable 30.0 V when reverse-biased above knee voltage |
Key Features
| Feature | Design Value |
|---|---|
| Metallurgical bond construction | Enables JANS-level radiation hardness and long-term parameter stability under thermal cycling |
| 1 µV/√Hz noise density | Supports sub-10 µV total noise in 1 kHz–3 kHz band for high-resolution sensor excitation |
| MIL-PRF-19500/435 qualification | Validated reliability for flight-critical subsystems including avionics power supervisors |
| Minimal capacitance (typ. <2 pF) | Preserves high-frequency response in RF bias networks and fast-switching protection circuits |
| Non-ESD-sensitive per MIL-STD-750 | Eliminates need for handling controls during manual assembly in defense production lines |
Applications
| Avionics Power Supervision | Downhole Instrumentation Reference |
|---|---|
Use Scenario: Monitoring 28 V DC bus in aircraft control units with ±10% input variation and -55°C to +125°C operating range. IC Role / Device Role / Timing Role: Primary voltage reference for comparator-based undervoltage lockout (UVLO) and overvoltage detection circuits. Use Value: Stable 30.0 V Zener point enables accurate trip thresholds despite thermal drift up to +0.095 %/°C, validated to JANTXV reliability level. |
Use Scenario: Providing bias voltage for piezoelectric sensor amplifiers in oil/gas well logging tools exposed to 175°C ambient and gamma radiation. IC Role / Device Role / Timing Role: Radiation-hardened voltage reference stabilizing op-amp gain-setting networks in analog front-ends. Use Value: Hermetic DO-35 package and metallurgical bond ensure no parameter shift after 100 krad(Si) exposure; 0.01 µA leakage prevents signal corruption at high source impedances. |
| Spacecraft Telemetry Regulator | Military Radio Frequency Bias |
Use Scenario: Generating clean 30 V reference for SAR ADC drivers in LEO satellite telemetry modules with strict EMI limits. IC Role / Device Role / Timing Role: Low-noise Zener source feeding precision DAC output buffers before RF upconversion stages. Use Value: 1 µV/√Hz noise density contributes <5 µV RMS integrated noise in 1–3 kHz band, meeting SNR > 100 dB requirement. |
Use Scenario: Setting gate bias for GaN HEMT amplifiers in tactical S-band transceivers operating from -40°C to +85°C. IC Role / Device Role / Timing Role: Temperature-compensated voltage clamp protecting amplifier input stages during transient overvoltage events. Use Value: +0.095 %/°C coefficient aligns with GaN device threshold drift, maintaining safe bias margin across full temperature range without active compensation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4749A | 30 V, 1 W, DO-41 package, ±5% tolerance, 200 Ω ZZT, +0.08 %/°C αVZ | Higher power rating but commercial-only qualification; no MIL-spec screening | Select for cost-sensitive industrial power supplies where JANTXV reliability is not required |
| CMZ30 | 30 V, 500 mW, DO-213AA surface-mount, ±5%, 200 Ω ZZT, +0.09 %/°C αVZ, RoHS | Same electrical specs in SMT form factor; lacks MIL-PRF-19500 qualification | Select when board space constraints mandate surface-mount packaging and radiation hardness is not needed |
Compared with 1N4120, 1N4749A offers higher power but no military qualification, while CMZ30 provides identical regulation performance in SMT format yet omits JANTXV screening-making 1N4120 the sole choice for programs requiring traceable mil-spec compliance and hermetic axial-leaded reliability.
Availability
1N4120 is available at Aetrix Electronics and suitable for avionics power supervision, downhole instrumentation reference, and spacecraft telemetry regulator applications requiring stable component supply with full traceability and long-term lifecycle support.
Supply support for 1N4120 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 1N4120 belongs to Microsemi's legacy MIL-qualified Zener diode family designed specifically for voltage regulation in mission-critical systems where parameter stability, radiation tolerance, and extended temperature operation are mandatory.
FAQ
What is the Zener voltage tolerance for 1N4120?
The 1N4120 has a nominal Zener voltage of 30.0 V with a standard tolerance of ±5%, as defined by JEDEC registration and confirmed in the Electrical Characteristics table on page 3 of T4-LDS-0245-2. This tolerance applies under thermal equilibrium at 25°C with 250 mA test current, and is consistent across JAN, JANTX, JANTXV, and JANS reliability levels.
Does 1N4120 require heatsinking in typical PCB layouts?
No additional heatsink is required for 1N4120 under standard conditions: its 500 mW power rating is supported by thermal resistance of 250°C/W junction-to-lead (measured at 10 mm lead length) and 300°C/W junction-to-ambient on FR4 with 4 mm² copper pads. Linear derating begins at 50°C lead temperature, reaching zero dissipation at 175°C.
Is 1N4120 RoHS compliant?
Yes, RoHS-compliant versions of 1N4120 are available with the "e3" suffix (e.g., 1N4120-1e3), but only for commercial-grade units. JANTXV and JANS versions retain traditional tin-lead plating per MIL-STD-750 method 2026 and are not RoHS compliant.
What is the maximum reverse leakage current for 1N4120?
The maximum reverse leakage current for 1N4120 is 0.01 µA measured at 22.8 V (76% of nominal 30.0 V Zener voltage), as specified in the Electrical Characteristics table. This ultra-low leakage supports high-impedance bias networks and battery-powered monitoring circuits where standby current must remain below 100 nA.
Can 1N4120 be used in surface-mount designs?
No-1N4120 is exclusively offered in the axial-leaded DO-35 (DO-204AH) glass package. For surface-mount equivalents, Microsemi offers the CMZ30 in DO-213AA package, which shares identical 30 V Zener voltage and 500 mW rating but lacks MIL-PRF-19500 qualification and hermetic axial construction.
1N4120 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- *
- Package/Case:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- -
- Tolerance:
- -
- Power - Max:
- -
- Impedance (Max) (Zzt):
- -
- Current - Reverse Leakage @ Vr:
- -
- Voltage - Forward (Vf) (Max) @ If:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- -
- Supplier Device Package:
- -
1N4120 FAQ
1.How can I place an order for 1N4120 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4120 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 1N4120 reliable?
The price and inventory of 1N4120 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4120 is usually 5 days.
3.What payment methods are accepted for 1N4120?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4120 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4120?
1N4120 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4120 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 1N4120?
For technical support, including 1N4120 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4120 requirements.
6.How does Aetrix verify that 1N4120 is sourced from the original manufacturer or authorized distributors?
All 1N4120 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 1N4120 meets industry standards.
7.What is the process for return or replacement of 1N4120?
All 1N4120 units undergo pre-shipment inspection (PSI). If there is an issue with 1N4120, 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 1N4120 part is unused and in its original packaging.
Return procedure for 1N4120:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4120 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…
