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onsemi 1N5937BRL
- Part No.:
- 1N5937BRL
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
1N5937BRL.pdf
- Description:
- DIODE ZENER 33V 3W AXIAL
- Quantity:
- Payment:
- Shipping:
Inventory:8,028
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Product details
Overview
1N5937BRL from onsemi is a 3 W, ±5% tolerance Zener diode in DO-41 (Case 59) axial package, with nominal Zener voltage of 33 V at 33 mA test current, maximum Zener impedance of 11.4 Ω at IZT, and reverse leakage ≤0.25 μA at 25.1 V. It delivers stable voltage regulation in power supply feedback loops, overvoltage protection circuits, and reference voltage generation for industrial power converters.
For engineers reviewing the 1N5937BRL datasheet, pinout, applications, or equivalent options, key selection criteria include its 33 V nominal Zener voltage, 3 W steady-state power rating at TL = 75°C, 98 W surge capability at 1 ms, ESD rating >16 kV (HBM), and DO-41 mechanical compatibility with legacy through-hole designs.
Technical Context
This device operates as a silicon-oxide passivated junction Zener regulator, optimized for stable DC voltage reference under fixed-current bias. Its thermal design relies on lead-to-ambient conduction (primary path via cathode lead), with junction-to-lead thermal resistance dependent on lead length-3/8″ leads yield ~30°C/W per Figure 2.
Electrical behavior is defined at TL = 30°C (measured 3/8″ from body); voltage drift with temperature is governed by a positive temperature coefficient typical of 33 V Zeners (~+10 mV/°C per Figure 6), and regulation accuracy is maintained within ±5% tolerance across production lots.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 31.35–34.65 V @ IZT = 33 mA - defines tight regulation window for precision 33 V reference applications |
| Power Dissipation (PD) | 3 W @ TL = 75°C - supports continuous operation in compact heatsink-limited layouts |
| Zener Impedance (ZZT) | 11.4 Ω max @ IZT - ensures low AC output impedance for ripple suppression in feedback networks |
| Surge Rating | 98 W @ 1 ms - enables robust transient overvoltage clamping without failure |
| ESD Rating | Class 3 (>16 kV HBM) - provides handling resilience during PCB assembly and field service |
| Reverse Leakage | ≤0.25 μA @ VR = 25.1 V - minimizes standby current loss in high-impedance bias networks |
| Package | DO-41 (Case 59), axial lead - compatible with standard through-hole insertion and wave-soldering processes |
Pinout & Package
Package: DO-41 (Case 59), axial-leaded, transfer-molded thermosetting plastic; cathode indicated by band; lead diameter uncontrolled within 0.71–0.86 mm; overall length 25.4 mm min; operating temperature range −65°C to +200°C.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (banded end) | Zener breakdown terminal | Connected to regulated output node; reverse-biased operation requires this terminal at higher potential than anode |
| Anode | Reference return path | Typically tied to system ground or lower-potential rail; completes current path during Zener conduction |
Key Features
| Feature | Design Value |
|---|---|
| ±5% Zener voltage tolerance | Guaranteed VZ spread (31.35–34.65 V) enables single-bin sourcing without calibration in cost-sensitive power supplies |
| 3 W steady-state dissipation | Supports higher current regulation (up to 90 mA at 33 V) than 1 W Zeners, reducing need for parallel devices |
| 98 W surge rating (1 ms) | Withstands lightning-induced transients or inductive kickback without degradation in industrial motor drives |
| ESD Class 3 (>16 kV HBM) | Eliminates pre-assembly ESD protection requirements, simplifying handling and test procedures |
| Pb-free (G suffix) compliance | Meets RoHS Directive 2011/65/EU and JEDEC J-STD-020 moisture sensitivity level 1 (unlimited floor life) |
Applications
| Switch-Mode Power Supply Feedback | Overvoltage Protection Clamp |
|---|---|
|
Use Scenario: Used in optocoupler-coupled feedback loop of 48 V output DC-DC converter to regulate output voltage against line/load variation. IC Role / Device Role / Timing Role: Zener reference element setting error amplifier threshold; replaces precision shunt regulator where ±5% tolerance is acceptable. Use Value: 33 V nominal VZ aligns with common TL431-based feedback thresholds; 11.4 Ω ZZT limits output ripple contribution to <15 mVpp. |
Use Scenario: Placed across DC bus of 36 V battery-powered motor controller to clamp surges exceeding 40 V. IC Role / Device Role / Timing Role: Passive overvoltage clamp; conducts only during fault events above 34.65 V, diverting energy to ground. Use Value: 98 W 1 ms surge rating absorbs 98 mJ pulses without parametric shift; DO-41 package allows direct mounting near bus terminals. |
| Industrial Sensor Reference | Programmable Logic Controller Input Conditioning |
|
Use Scenario: Provides stable 33 V reference for ratiometric bridge sensor excitation in 0–100°C ambient industrial temperature transmitters. IC Role / Device Role / Timing Role: Precision voltage source for Wheatstone bridge bias; operates in constant-current mode with series resistor. Use Value: −65°C to +200°C operating range ensures functionality across full industrial spec; <0.25 μA leakage prevents loading of high-Z sensor outputs. |
Use Scenario: Clamps input signal to PLC digital input module rated for 24 V nominal, protecting against accidental 48 V miswiring. IC Role / Device Role / Timing Role: Input voltage limiter; placed between field wiring and input Schmitt trigger to prevent latch-up. Use Value: 31.35 V minimum VZ guarantees conduction before damage threshold of downstream logic; axial DO-41 allows easy field replacement. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N5937B (tube) | Identical electrical specs and DO-41 package; differs only in packaging (2000/unit box vs. 6000/tape-and-reel) | No functional difference; suitable for manual prototyping or low-volume hand-soldered assemblies | Select 1N5937B when reel automation is unnecessary and smaller lot sizes reduce inventory overhead |
| MMBZ5265BLT1G | SOT-23 surface-mount package; same 33 V nominal VZ, but lower 0.25 W power rating and 30 Ω ZZT | Not suitable for >100 mA regulation or surge clamping; intended for space-constrained logic-level protection | Choose MMBZ5265BLT1G only for PCB area-limited designs where 3 W dissipation is not required |
Compared with 1N5937BRL, the 1N5937B offers identical performance in non-automated assembly, while MMBZ5265BLT1G trades power handling and impedance for miniaturization-making 1N5937BRL optimal for through-hole power regulation where reliability under surge and thermal stress is critical.
Availability
1N5937BRL is available at Aetrix Electronics and suitable for industrial power supplies, motor drive protection circuits, and programmable logic controller input conditioning requiring stable component supply, long-term obsolescence management, and RoHS-compliant procurement.
Supply support for 1N5937BRL 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
onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.
The 1N59xxB Series is part of onsemi's legacy Zener regulator portfolio designed for robust, cost-effective voltage reference and clamping in high-reliability industrial and power conversion systems.
FAQ
What is the Zener voltage tolerance of the 1N5937BRL?
The 1N5937BRL has a guaranteed ±5% tolerance on its nominal Zener voltage of 33 V, meaning the actual measured VZ falls between 31.35 V and 34.65 V when tested at IZT = 33 mA and TL = 30°C. This tolerance is confirmed in the Electrical Characteristics table of the official onsemi datasheet (Rev. 9, July 2024) and applies across the full operating temperature range.
Can the 1N5937BRL be used in surface-mount designs?
No-the 1N5937BRL uses a DO-41 axial-leaded package (Case 59) and is not compatible with surface-mount assembly. It requires through-hole mounting and wave or selective soldering. For SMT equivalents, consider the MMBZ5265BLT1G (SOT-23), though it offers only 0.25 W power rating versus the 1N5937BRL's 3 W capability.
What is the maximum surge power the 1N5937BRL can withstand?
The 1N5937BRL is rated for 98 W nonrepetitive surge power at 1 ms pulse width, as specified in the Maximum Ratings table of the onsemi datasheet. This rating assumes rectangular waveform and TJ = 25°C prior to pulse; exceeding this limit risks irreversible junction damage even if average power remains within 3 W limits.
How does temperature affect the Zener voltage of the 1N5937BRL?
The 1N5937BRL exhibits a positive temperature coefficient of approximately +10 mV/°C near its 33 V operating point, as shown in Figure 6 of the onsemi datasheet. This means VZ increases linearly with junction temperature-critical for designs operating across −40°C to +85°C ambient where thermal drift must be modeled using TJ = TL + θJL·PD.
Is the 1N5937BRL RoHS compliant and lead-free?
Yes-the "G" suffix in the full ordering code 1N5937BRL,G confirms Pb-free construction per JEDEC J-STD-020. The device uses lead-free terminations and complies with EU RoHS Directive 2011/65/EU. Packaging markings may include a microdot or "G" to indicate compliance, and the datasheet explicitly states "Pb−Free Packages are Available" in the Features section.
1N5937BRL Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- DO-204AL, DO-41, Axial
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Voltage - Zener (Nom) (Vz):
- 33 V
- Tolerance:
- ±5%
- Power - Max:
- 3 W
- Impedance (Max) (Zzt):
- 33 Ohms
- Current - Reverse Leakage @ Vr:
- 1 µA @ 25.1 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.5 V @ 200 mA
- Operating Temperature:
- -65°C ~ 200°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- Axial
1N5937BRL FAQ
1.How can I place an order for 1N5937BRL through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N5937BRL 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 1N5937BRL reliable?
The price and inventory of 1N5937BRL are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N5937BRL is usually 5 days.
3.What payment methods are accepted for 1N5937BRL?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N5937BRL transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N5937BRL?
1N5937BRL orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N5937BRL 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 1N5937BRL?
For technical support, including 1N5937BRL datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N5937BRL requirements.
6.How does Aetrix verify that 1N5937BRL is sourced from the original manufacturer or authorized distributors?
All 1N5937BRL 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 1N5937BRL meets industry standards.
7.What is the process for return or replacement of 1N5937BRL?
All 1N5937BRL units undergo pre-shipment inspection (PSI). If there is an issue with 1N5937BRL, 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 1N5937BRL part is unused and in its original packaging.
Return procedure for 1N5937BRL:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N5937BRL Tags
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