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Microchip Technology 1N984B
- Part No.:
- 1N984B
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-204AH, DO-35, Axial
- Datasheet:
-
1N984B.pdf
- Description:
- DIODE ZENER 91V 500MW DO204AH
- Quantity:
- Payment:
- Shipping:
Inventory:2,626
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Product details
Overview
1N984B from Microsemi is a silicon 500 mW axial-leaded Zener diode in DO-35 (DO-204AH) package, rated for 91 V nominal Zener voltage with ±5% tolerance, 1.4 mA Zener test current, 400 Ω maximum Zener impedance at IZT, and −65°C to +175°C operating temperature range. It serves as a precision voltage reference or overvoltage clamp in low-power analog circuits, power supply feedback loops, and industrial sensor conditioning stages.
For engineers reviewing the 1N984B datasheet, 1N984B pinout, 1N984B application, or 1N984B equivalent, key selection criteria include its 91 V regulation point, 400 Ω dynamic impedance, thermal resistance of 250 °C/W (junction-to-lead), JEDEC-registered B-suffix tolerance, and DO-35 glass-body construction suitable for high-reliability, wide-temperature environments.
Technical Context
The 1N984B operates as a reverse-biased voltage-regulating diode with a sharp breakdown knee verified per JEDEC standards. Its Zener voltage is specified at 1.4 mA test current (IZT) and exhibits a +0.099 %/°C temperature coefficient, indicating stable regulation above ~50 V.
It delivers 500 mW steady-state power dissipation at lead temperature <50°C (3/8" from body), derating linearly to zero at 175°C. Maximum DC Zener current is 4.1 mA, and surge current capability is 21 A for 1/120 sec pulses - enabling transient suppression in low-energy circuits.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Nominal Zener Voltage | 91 V ±5% - defines precise clamping/reference level for feedback or protection circuits |
| Zener Test Current (IZT) | 1.4 mA - operating point where VZ and ZZT are guaranteed per JEDEC |
| Zener Impedance (ZZT) | 400 Ω max @ IZT - determines regulation stiffness under varying load current |
| Max DC Zener Current (IZM) | 4.1 mA - sets upper limit for continuous regulation without exceeding 400 mW at 75°C lead temp |
| Reverse Leakage Current | 5 μA @ 5 V - ensures minimal parasitic current in standby or high-impedance bias networks |
| Temp Coefficient (αVZ) | +0.099 %/°C - quantifies voltage drift with ambient temperature change in precision references |
| Package | DO-35 (DO-204AH) - hermetically sealed glass axial-leaded package rated for −65°C to +175°C operation |
| Power Dissipation | 500 mW @ TL < 50°C - usable power budget for thermal design on PCB or chassis mount |
Pinout & Package
DO-35 (DO-204AH) glass axial-leaded package with cathode indicated by a single black band; anode is unmarked lead. Hermetically sealed, tin-lead or RoHS-compliant matte-tin plating, weight 0.2 g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Zener cathode reference ground | Connected to circuit common or lower-potential node; reverse bias applied across anode–cathode for regulation |
| Cathode | Zener breakdown terminal / regulated output node | Banded end; held at stable 91 V above anode when reverse current ≥1.4 mA flows |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-registered 1N984B | Guarantees standardized electrical behavior and interchangeability across qualified suppliers |
| ±5% Zener voltage tolerance (B suffix) | Enables predictable regulation without post-manufacture trimming in cost-sensitive designs |
| −65°C to +175°C operating range | Supports deployment in aerospace, downhole, and automotive under-hood applications |
| Nonsensitive to ESD (MIL-STD-750 Method 1020) | Eliminates need for external ESD protection during handling and assembly |
| Inherently radiation-hardened | Validated per Microsemi MicroNote 050 for use in space-grade and nuclear instrumentation systems |
| Minimal capacitance (typ. <2 pF) | Preserves high-frequency signal integrity in RF biasing and fast transient detection circuits |
Applications
| Industrial Power Supply Feedback | High-Temperature Sensor Reference |
|---|---|
Use Scenario: Regulating output voltage in isolated flyback or forward converter feedback networks using optocoupler-coupled error amplifiers. IC Role / Device Role / Timing Role: Precision voltage reference providing stable 91 V threshold for error amplifier bias and compensation. Use Value: Maintains ±1% output regulation across line/load/temperature with no active components in the reference path. |
Use Scenario: Providing stable bias voltage for RTD or thermocouple signal conditioning circuits in oil/gas downhole tools. IC Role / Device Role / Timing Role: Temperature-stable reference source for analog front-end gain-setting and offset calibration. Use Value: +0.099 %/°C coefficient minimizes drift-induced measurement error up to +175°C ambient. |
| Military Avionics Overvoltage Clamp | Test Equipment Calibration Standard |
Use Scenario: Protecting 100 V-rated analog inputs in MIL-STD-704 aircraft power monitoring systems from transients. IC Role / Device Role / Timing Role: Fast-response shunt clamp limiting input voltage to ≤91 V during 100 V surge events. Use Value: 21 A surge rating (1/120 s) absorbs energy without failure, preserving downstream ADC and protection ICs. |
Use Scenario: Serving as traceable 91 V reference in benchtop multimeter and calibrator self-test routines. IC Role / Device Role / Timing Role: Primary voltage standard in automated calibration sequences requiring NIST-traceable stability. Use Value: JEDEC registration and ±5% tolerance ensure repeatability across production units and field service units. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N984A | ±10% Zener voltage tolerance vs. ±5% for 1N984B; otherwise identical electrical and thermal specs | Acceptable where system-level tolerance budgets allow wider regulation band (e.g., non-critical biasing) | Select 1N984A only if cost reduction outweighs need for tighter voltage accuracy |
| MMBZ5257B | Surface-mount SOT-23 package; 91 V ±5%, but lower 225 mW power rating and 300 Ω ZZT | Used in space-constrained PCBs where DO-35 axial leads are incompatible with automated assembly | Choose MMBZ5257B only when board real estate or reflow compatibility is prioritized over power handling |
Compared with 1N984A and MMBZ5257B, the 1N984B uniquely balances 500 mW power capability, JEDEC-standardized DO-35 form factor, and ±5% tolerance-making it optimal for high-reliability through-hole designs requiring robust thermal margin and long-term stability.
Availability
1N984B is available at Aetrix Electronics and suitable for industrial power supplies, high-temperature sensor interfaces, and military avionics requiring stable component supply with full traceability and extended temperature support.
Supply support for 1N984B 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 (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability, radiation-hardened, and high-temperature analog and mixed-signal components.
The 1N957B–1N992B series was designed specifically for mission-critical voltage regulation in aerospace, defense, and industrial systems demanding extended temperature operation and JEDEC-standardized performance.
FAQ
What is the Zener voltage tolerance for 1N984B?
The 1N984B has a nominal Zener voltage of 91 V with a ±5% tolerance, as indicated by the "B" suffix per JEDEC standard. This means the actual measured VZ at 1.4 mA test current falls between 86.45 V and 95.55 V at 25°C. The tolerance is guaranteed across the full −65°C to +175°C operating range, though voltage drift due to temperature is governed by the +0.099 %/°C coefficient.
Can 1N984B be used in surface-mount designs?
No - the 1N984B is packaged exclusively in the axial-leaded DO-35 (DO-204AH) glass case and is not compatible with SMT assembly. For surface-mount equivalents, Microsemi offers the MLL984B in DO-213AA (MELF) package, or third-party alternatives like MMBZ5257B in SOT-23. The 1N984B requires through-hole mounting with 3/8" lead length for thermal rating compliance.
What is the maximum surge current rating for 1N984B?
The 1N984B supports a maximum surge current (IZSM) of 21 A for a pulse duration of 1/120 second (≈8.3 ms), per Note 5 in the datasheet. This rating applies to square-wave or half-sine wave transients and enables the 1N984B to absorb short-duration overvoltage events without degradation, provided average power remains within 500 mW limits.
Is 1N984B RoHS compliant?
Yes - the standard 1N984B is not RoHS compliant by default, but RoHS-compliant versions are available by adding the "e3" suffix (i.e., 1N984Be3), which denotes annealed matte-tin plating per JEDEC and Microsemi specifications. Both versions share identical electrical and thermal characteristics; only the plating composition differs.
How does the temperature coefficient affect 1N984B's regulation accuracy?
The 1N984B has a +0.099 %/°C temperature coefficient, meaning its Zener voltage increases by approximately 90 mV per °C rise above 25°C. At +125°C, VZ rises by ~9.9 V - critical for high-temperature applications. Designers must account for this drift in precision references; the 1N984B remains suitable where absolute accuracy is secondary to robustness and wide-temperature operation.
1N984B Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-204AH, DO-35, Axial
- Packaging:
- Bulk
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 91 V
- Tolerance:
- ±5%
- Power - Max:
- 500 mW
- Impedance (Max) (Zzt):
- 400 Ohms
- Current - Reverse Leakage @ Vr:
- 5 µA @ 69.2 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.1 V @ 200 mA
- Operating Temperature:
- -65°C ~ 175°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-204AH (DO-35)
1N984B FAQ
1.How can I place an order for 1N984B through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N984B 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 1N984B reliable?
The price and inventory of 1N984B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N984B is usually 5 days.
3.What payment methods are accepted for 1N984B?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N984B transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N984B?
1N984B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N984B 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 1N984B?
For technical support, including 1N984B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N984B requirements.
6.How does Aetrix verify that 1N984B is sourced from the original manufacturer or authorized distributors?
All 1N984B 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 1N984B meets industry standards.
7.What is the process for return or replacement of 1N984B?
All 1N984B units undergo pre-shipment inspection (PSI). If there is an issue with 1N984B, 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 1N984B part is unused and in its original packaging.
Return procedure for 1N984B:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N984B 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
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