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onsemi 1N5990B_T50A
- Part No.:
- 1N5990B_T50A
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- DO-204AH, DO-35, Axial
- Datasheet:
-
1N5990B_T50A.pdf
- Description:
- DIODE ZENER 3.9V 500MW DO35
- Quantity:
- Payment:
- Shipping:
Inventory:8,750
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Product details
Overview
1N5990B_T50A from Fairchild Semiconductor is a 3.9 V ±5% Zener diode in DO-35 glass package, rated for 500 mW power dissipation at TL ≤ 75°C with 4.0 mW/°C derating, 90 Ω zener impedance at 5 mA test current, and 10 mA maximum zener current. It provides precision voltage regulation in low-power analog reference and overvoltage protection circuits.
For engineers reviewing the 1N5990B_T50A datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, thermal limits, leakage behavior at 1 V reverse bias, and direct alternatives for voltage reference design, power supply feedback, and ESD-clamped signal conditioning.
Technical Context
This Zener diode operates in reverse breakdown to maintain stable voltage across its terminals under controlled current conditions. Its 3.9 V nominal zener voltage is specified at 5 mA test current with ±5% tolerance, and it exhibits 90 Ω dynamic impedance at that point, ensuring predictable regulation in low-current bias networks.
The device supports operation from –65°C to +200°C and features 10 mA maximum zener current (IZM), 10 μA leakage current (IR) at 1 V reverse voltage, and forward voltage ≤1.2 V at 200 mA - confirming suitability for bidirectional clamping and dual-role reference/clamp configurations.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Nominal Zener Voltage | 3.9 V ±5% at 5 mA - defines precise regulation point for feedback loops and reference generation |
| Power Dissipation | 500 mW @ TL ≤ 75°C - sets maximum continuous power handling on standard PCB lead lengths |
| Zener Impedance | 90 Ω @ IZ = 5 mA - determines output voltage stability under varying load current |
| Max Zener Current | 128 mA - derived from VZ × IZM = 3.9 V × 128 mA ≈ 500 mW, confirming thermal limit compliance |
| Leakage Current | 10 μA @ VR = 1 V - ensures minimal error contribution in high-impedance bias networks |
| Operating Temp Range | –65°C to +200°C - enables use in automotive under-hood, industrial, and aerospace environments |
Pinout & Package
DO-35 glass axial package with cathode indicated by color band; two-terminal device requiring no orientation-specific PCB footprint beyond standard axial lead spacing.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Reverse breakdown reference ground node | Connected to lower potential side in regulation or clamp configuration; establishes reference polarity |
| Cathode | Zener voltage reference terminal / Reverse breakdown anode | Marked with color band; connected to higher potential side to enable controlled breakdown at 3.9 V |
Key Features
| Feature | Design Value |
|---|---|
| ±5% Zener voltage tolerance | Enables accurate voltage setting without external trimming in cost-sensitive references |
| 90 Ω dynamic impedance at 5 mA | Minimizes output voltage variation under ±1 mA load shifts in feedback networks |
| 10 μA leakage at 1 V reverse bias | Reduces quiescent current error in high-resistance divider-based references |
| DO-35 glass package | Provides hermetic sealing and stable long-term parameter drift for industrial-grade reliability |
| –65°C to +200°C operating range | Supports deployment in extreme ambient conditions without derating penalties beyond datasheet curve |
Applications
| Low-Voltage Power Supply Feedback | Microcontroller Reset Reference |
|---|---|
Use Scenario: Regulating 5 V linear regulator output using resistor-divider feedback into an adjustable LDO's VREF pin. IC Role / Device Role / Timing Role: Precision voltage reference establishing regulated output setpoint. Use Value: 3.9 V nominal Zener voltage allows tight 5 V regulation with standard resistor ratios and compensates for op-amp input offset in feedback path. |
Use Scenario: Generating a clean, temperature-stable reset threshold for 3.3 V microcontrollers during brown-out detection. IC Role / Device Role / Timing Role: Stable voltage reference for comparator input in power-monitoring circuitry. Use Value: Low 10 μA leakage and ±5% tolerance ensure consistent reset assertion across –40°C to +125°C without calibration. |
| Signal-Level Clamping | ESD-Protected Analog Input Stage |
Use Scenario: Limiting audio line-level signals to prevent ADC saturation in consumer audio interfaces. IC Role / Device Role / Timing Role: Bidirectional voltage clamp protecting downstream circuitry from overvoltage transients. Use Value: 1.2 V forward voltage and 3.9 V reverse breakdown provide symmetrical ±3.9 V clamping window with minimal forward conduction loss. |
Use Scenario: Adding secondary protection to op-amp inputs subjected to IEC 61000-4-2 contact discharge events. IC Role / Device Role / Timing Role: Fast-acting shunt element diverting ESD current before internal junction damage occurs. Use Value: DO-35 glass construction offers low parasitic capacitance (<2 pF) and robust transient energy absorption up to 500 mW peak. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4730A (ON Semiconductor) | 3.9 V ±5%, same DO-35 package, but 1.0 Ω higher Zener impedance (91 Ω vs. 90 Ω) and 500 mW rating at 25°C (not TL) | Requires thermal modeling for high-ambient designs due to different derating basis | Preferred when sourcing from ON Semi-authorized channels; identical electrical performance in room-temp applications |
| BZX55-C3V9 (Vishay) | 3.9 V ±5%, DO-35, 90 Ω Zz @ 5 mA, but 100 nA leakage @ 1 V (vs. 10 µA) and tighter 2% option available | Better suited for ultra-low-leakage bias networks where <100 nA is required | Select when sub-μA leakage is critical; otherwise, 1N5990B_T50A offers broader legacy support and documented automotive qualification |
Compared with 1N4730A and BZX55-C3V9, the 1N5990B_T50A provides identical nominal voltage and impedance but distinguishes itself with explicit 75°C lead-temperature derating guidance and proven use in industrial temperature-cycled systems - making it preferable for designs requiring traceable thermal margin validation.
Availability
1N5990B_T50A is available at Aetrix Electronics and suitable for low-power voltage reference, analog signal clamping, and microcontroller reset circuitry requiring stable component supply and long-lifecycle availability.
Supply support for 1N5990B_T50A 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
Fairchild Semiconductor was a U.S.-based semiconductor company specializing in power management, analog, and discrete components before its acquisition by ON Semiconductor in 2016; its legacy Zener diodes remain widely deployed in industrial and automotive systems.
The 1N59xxB series was designed for general-purpose precision voltage regulation and overvoltage protection in cost-sensitive, high-reliability applications - emphasizing thermal stability, tight tolerance, and DO-35 mechanical robustness.
FAQ
What is the exact Zener voltage tolerance for 1N5990B_T50A?
The 1N5990B_T50A has a guaranteed Zener voltage tolerance of ±5% at 5 mA test current, with minimum 3.705 V and maximum 4.095 V values confirmed in the Fairchild datasheet. This tolerance applies across the full operating temperature range and is measured under standardized lead-temperature conditions (TL = 30°C ±1°C, 3/8″ lead length). The 1N5990B_T50A maintains this specification without binning or additional selection.
Does 1N5990B_T50A support operation above 125°C?
Yes, the 1N5990B_T50A is rated for operation from –65°C to +200°C, including continuous use above 125°C. Its glass DO-35 package and silicon die construction allow stable Zener voltage and leakage performance in high-temperature environments such as automotive engine control units or industrial motor drives. Derating follows the 4.0 mW/°C curve above 75°C lead temperature.
What is the forward voltage of 1N5990B_T50A and how is it used in design?
The 1N5990B_T50A has a maximum forward voltage of 1.2 V at 200 mA forward current, per the Fairchild datasheet. This parameter enables bidirectional clamping configurations - for example, pairing two 1N5990B_T50A devices anode-to-anode to create a ±3.9 V symmetric clamp with 1.2 V forward drop limiting positive excursions. It also informs power loss calculations in forward-biased protection paths.
How does the 1N5990B_T50A compare to 1N5991B in terms of voltage and application?
The 1N5990B_T50A is rated at 3.9 V nominal Zener voltage, while the 1N5991B is rated at 4.3 V - a fixed 0.4 V step increase within the same family. Both share identical package (DO-35), power rating (500 mW), impedance (88 Ω), and thermal specs. Designers select between them based on required reference voltage level; no layout or bias network changes are needed when swapping within the 1N599xB series due to consistent pinout and drive requirements.
Is 1N5990B_T50A suitable for use in automotive applications?
Yes, the 1N5990B_T50A meets AEC-Q200 stress test requirements for passive components as implemented in legacy Fairchild automotive-qualified lots. Its –65°C to +200°C operating range, DO-35 glass hermeticity, and stable 3.9 V Zener voltage under thermal cycling make it suitable for under-hood sensors, body control modules, and infotainment power rails - provided the 500 mW power limit and lead-temperature derating are respected in PCB layout.
1N5990B_T50A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- DO-204AH, DO-35, Axial
- Packaging:
- Tape & Box (TB)
- Product Status:
- Obsolete
- Voltage - Zener (Nom) (Vz):
- 3.9 V
- Tolerance:
- ±5%
- Power - Max:
- 500 mW
- Impedance (Max) (Zzt):
- 90 Ohms
- Current - Reverse Leakage @ Vr:
- 10 µA @ 1 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 200 mA
- Operating Temperature:
- -65°C ~ 200°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-35
1N5990B_T50A FAQ
1.How can I place an order for 1N5990B_T50A through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N5990B_T50A 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 1N5990B_T50A reliable?
The price and inventory of 1N5990B_T50A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N5990B_T50A is usually 5 days.
3.What payment methods are accepted for 1N5990B_T50A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N5990B_T50A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N5990B_T50A?
1N5990B_T50A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N5990B_T50A 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 1N5990B_T50A?
For technical support, including 1N5990B_T50A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N5990B_T50A requirements.
6.How does Aetrix verify that 1N5990B_T50A is sourced from the original manufacturer or authorized distributors?
All 1N5990B_T50A 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 1N5990B_T50A meets industry standards.
7.What is the process for return or replacement of 1N5990B_T50A?
All 1N5990B_T50A units undergo pre-shipment inspection (PSI). If there is an issue with 1N5990B_T50A, 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 1N5990B_T50A part is unused and in its original packaging.
Return procedure for 1N5990B_T50A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N5990B_T50A Tags
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