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Renesas RD9.1F
- Part No.:
- RD9.1F
- Manufacturer:
- Renesas
- Category:
- Single Zener Diodes
- Package:
- -
- Datasheet:
-
RD9.1F.pdf
- Description:
- DIODE ZENER
- Quantity:
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Inventory:55,531
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Product details
Overview
RD9.1F from Renesas Electronics is a 1 W planar-type silicon Zener diode in DO-41 glass-sealed DHD (Double Heatsink Diode) package, with nominal zener voltage 9.1 V (B3 grade: 8.91–9.38 V), dynamic impedance ≤6 Ω at 40 mA, and temperature coefficient +5.5 mV/°C. It delivers stable voltage regulation in power supply reference and overvoltage protection circuits for industrial control modules.
For engineers reviewing the RD9.1F datasheet, RD9.1F pinout, RD9.1F application, or RD9.1F equivalent, this page provides verified electrical specifications, thermal derating behavior, JEDEC DO-41 terminal mapping, real-world clipping/limiter use cases, and two validated alternative Zener diodes with comparable voltage tolerance, power rating, and thermal performance.
Technical Context
The RD9.1F operates as a two-terminal voltage reference device with reverse-biased junction conduction. Its zener breakdown is engineered for tight voltage tolerance (±2.7% for B3 grade) and low dynamic impedance (6 Ω max at IZ = 40 mA), enabling precise regulation under varying load conditions.
Thermal design is constrained by a maximum junction temperature of 175°C and a surge reverse power rating of 400 W for 10 μs pulses. The DO-41 package provides defined thermal resistance characteristics dependent on PCB copper area (Rth = 240°C/W at S = 5 mm²).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 8.91–9.38 V (B3 grade, tested at 40 ms after power-on; ensures ±2.7% tolerance in production calibration) |
| Power Dissipation (P) | 1.0 W at TA = 25°C; derates linearly to zero at 150°C ambient per Figure 1 - defines maximum continuous DC bias capability |
| Dynamic Impedance (ZZ) | ≤6 Ω at IZ = 40 mA - enables <10 mV output variation for ±10 mA load current shifts in reference circuits |
| Reverse Current (IR) | ≤20 μA at VR = 7.0 V - guarantees minimal leakage in high-impedance limiter or clamp nodes |
| Temp. Coefficient (γZ) | +5.5 mV/°C (typical) - predictable positive drift supports temperature-compensated reference designs |
| Surge Power (PRSM) | 400 W for t = 10 μs (non-repetitive) - absorbs transient spikes without failure in surge suppression applications |
| Junction Temperature (Tj) | 175°C maximum - sets upper limit for thermal design margin in enclosed or high-ambient environments |
Pinout & Package
RD9.1F uses the JEDEC-standard DO-41 axial glass package (3.0 mm diameter × 5.0 mm length), with cathode indicated by a black band. Thermal performance depends on PCB copper area (S), with Rth ranging from 240°C/W (S = 5 mm²) to 40°C/W (S = 20 mm²).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / reference ground node | Connected to circuit common; establishes reference potential when cathode is biased above it |
| Cathode | Zener breakdown terminal / regulated output node | Marked with black band; supplies stable 9.1 V when reverse-biased at ≥40 mA |
Key Features
| Feature | Design Value |
|---|---|
| Wide zener voltage range (2–82 V) | Enables single-family standardization across >40 voltage points - reduces BOM complexity for multi-rail systems |
| E24 series nominal values | Guarantees compatibility with standard resistor/capacitor value selection - simplifies analog design iteration |
| Planar-type glass-sealed DHD structure | Provides robust mechanical stability and repeatable thermal interface - critical for long-term reliability in industrial environments |
| B1/B2/B3 grading options | Allows selective binning (e.g., RD9.1F B3) for tighter voltage matching in precision references or matched-clamp arrays |
| 175°C maximum junction temperature | Supports operation in high-temperature enclosures (e.g., motor drives, power converters) without derating penalties below 150°C ambient |
Applications
| Power Supply Reference | Overvoltage Limiter |
|---|---|
Use Scenario: Stabilizing feedback voltage in linear regulator ICs or op-amp-based adjustable supplies. IC Role / Device Role / Timing Role: Provides fixed 9.1 V reference for error amplifier comparison - sets output voltage accuracy and line/load regulation. Use Value: Low ZZ (≤6 Ω) minimizes output deviation under dynamic load steps; +5.5 mV/°C γZ allows predictable compensation in temperature-critical rails. |
Use Scenario: Clamping input signals to protect ADC front-ends or microcontroller GPIO pins from ESD or inductive kickback. IC Role / Device Role / Timing Role: Acts as passive shunt limiter - conducts excess energy above 9.1 V to ground before downstream components reach breakdown. Use Value: 400 W surge rating handles 10 μs transients (e.g., relay coil flyback); 20 μA leakage at 7 V preserves signal integrity in high-Z sensor interfaces. |
| Waveform Clipper | Surge Absorption |
Use Scenario: Symmetric or asymmetric clipping of audio or control waveforms in analog signal conditioning stages. IC Role / Device Role / Timing Role: Nonlinear voltage-dependent switch - limits peak amplitude while preserving waveform shape below threshold. Use Value: Sharp knee at 9.1 V (B3 grade) ensures consistent clipping level across production units; DO-41 package enables through-hole mounting in serviceable test equipment. |
Use Scenario: Primary-stage transient voltage suppression on DC power inputs of industrial PLCs or motor controllers. IC Role / Device Role / Timing Role: Fast-acting energy sink - diverts surge current away from upstream regulators or downstream logic during lightning-induced surges. Use Value: 1 W continuous dissipation sustains clamping during sustained overvoltage events; 175°C Tj rating prevents thermal runaway in unventilated enclosures. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ON Semiconductor 1N4739A | 9.1 V nominal (±5%), 1 W, DO-41, ZZ ≤10 Ω at 28 mA - higher impedance and looser tolerance than RD9.1F B3 | Acceptable where ±5% regulation is sufficient; not suitable for precision reference designs requiring <±3% tolerance | Select RD9.1F when tighter voltage binning (B3) and lower ZZ are required for stable feedback loops. |
| Vishay 1N5239B | 9.1 V nominal (±5%), 0.5 W, DO-35 - half the power rating and smaller package than RD9.1F | Limited to low-power signal-level clamping; cannot sustain 1 W continuous dissipation or 400 W surge loads | Choose RD9.1F for industrial-grade power rail protection where thermal mass and surge resilience are mandatory. |
Compared with 1N4739A and 1N5239B, RD9.1F offers tighter B3-grade voltage tolerance (±2.7% vs. ±5%), lower dynamic impedance (6 Ω vs. ≥10 Ω), and full 1 W continuous rating - making it preferable for high-stability reference and high-energy surge absorption where precision and ruggedness are jointly required.
Availability
RD9.1F is available at Aetrix Electronics and suitable for industrial control systems, power supply reference circuits, and overvoltage protection applications requiring stable component supply, long-lifecycle support, and traceable sourcing.
Supply support for RD9.1F 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
Renesas Electronics Corporation is a global semiconductor manufacturer specializing in microcontrollers, analog, and power devices for industrial, automotive, and infrastructure markets.
RD9.1F belongs to Renesas' legacy planar Zener diode family designed for general-purpose voltage regulation and transient suppression in Standard-grade applications including industrial automation, office equipment, and communications hardware.
FAQ
What is the exact zener voltage tolerance for RD9.1F?
The RD9.1F is offered in B3 grade, with a guaranteed zener voltage range of 8.91 V to 9.38 V at 40 mA test current - representing ±2.7% tolerance around the nominal 9.1 V value. This tighter binning is confirmed in the official Renesas datasheet D13936EJ5V0DS, page 3, and applies specifically to RD9.1F B3 units.
Does RD9.1F support surge protection, and what is its pulse rating?
Yes, RD9.1F is rated for non-repetitive surge reverse power of 400 W at pulse width t = 10 μs (per Figure 7 in datasheet D13936EJ5V0DS). This makes RD9.1F suitable for absorbing short-duration transients such as relay coil flyback or ESD events, provided average power remains within 1 W continuous limit.
What is the thermal resistance characteristic of RD9.1F, and how does PCB layout affect it?
RD9.1F's thermal resistance (Rth) varies with printed foil area (S): 240°C/W at S = 5 mm², 120°C/W at S = 10 mm², and 40°C/W at S = 20 mm² (Figure 2, datasheet D13936EJ5V0DS). Increasing copper area directly lowers junction-to-ambient thermal resistance - critical for sustaining 1 W dissipation in compact or high-ambient designs.
Is RD9.1F RoHS compliant, and what is its quality grade?
RD9.1F is classified as "Standard" quality grade per Renesas documentation (page 7, note under Quality Grades), intended for computers, office equipment, industrial robots, and communications gear. While RoHS compliance is not explicitly stated in the 2006 datasheet, Renesas confirms all active products meet EU RoHS Directive requirements - verify latest status via Renesas sales office or product change notices.
Can RD9.1F be used in place of older NEC-brand Zeners like NEC RD9.1F?
Yes - RD9.1F is the direct successor to the same-numbered part previously branded by NEC Electronics. As confirmed in the April 2010 merger notice, Renesas Electronics assumed full responsibility for all NEC product lines, including RD9.1F, with identical specifications, packaging, and datasheet continuity (Document No. D13936EJ5V0DS remains valid).
RD9.1F Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- 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:
- -
RD9.1F FAQ
1.How can I place an order for RD9.1F through Aetrix?
Please submit a Request for Quotation (RFQ) for RD9.1F 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 RD9.1F reliable?
The price and inventory of RD9.1F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for RD9.1F is usually 5 days.
3.What payment methods are accepted for RD9.1F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for RD9.1F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for RD9.1F?
RD9.1F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your RD9.1F 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 RD9.1F?
For technical support, including RD9.1F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your RD9.1F requirements.
6.How does Aetrix verify that RD9.1F is sourced from the original manufacturer or authorized distributors?
All RD9.1F 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 RD9.1F meets industry standards.
7.What is the process for return or replacement of RD9.1F?
All RD9.1F units undergo pre-shipment inspection (PSI). If there is an issue with RD9.1F, 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 RD9.1F part is unused and in its original packaging.
Return procedure for RD9.1F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
RD9.1F Tags
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