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Renesas RD4.7F
- Part No.:
- RD4.7F
- Manufacturer:
- Renesas
- Category:
- Single Zener Diodes
- Package:
- -
- Datasheet:
-
RD4.7F.pdf
- Description:
- DIODE ZENER
- Quantity:
- Payment:
- Shipping:
Inventory:127,636
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Product details
Overview
RD4.7F 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 4.7 V (B3 grade: 4.66–4.91 V), dynamic impedance ≤10 Ω at 40 mA, and reverse current ≤20 μA at 2.0 V. It serves as a precision voltage reference and overvoltage clamp in power supply regulation circuits.
For engineers reviewing the RD4.7F datasheet, RD4.7F pinout, RD4.7F application, or RD4.7F equivalent, this page delivers verified electrical specs, thermal derating curves, zener temperature coefficient (−1.5 mV/°C), surge capability (400 W @ 10 μs), and direct alternatives for voltage reference and transient suppression design.
Technical Context
The RD4.7F operates as a two-terminal voltage-regulating device using avalanche breakdown in its planar silicon junction. Its zener voltage is specified at IZ = 40 mA, with tight tolerance (±2.5% for B3 grade) and low dynamic impedance to maintain stable regulation under load variation.
Thermal performance is defined by junction-to-ambient thermal resistance (RthJA) dependent on PCB copper area - e.g., 200°C/W at 5 mm² foil, improving to 80°C/W at 20 mm². The −1.5 mV/°C temperature coefficient indicates slight negative drift, suitable for ambient-stable biasing where moderate tempco is acceptable.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 4.66–4.91 V at IZ = 40 mA - defines regulated output voltage window for reference or clamping |
| Power Dissipation (P) | 1.0 W at TA = 25°C - sets maximum continuous DC power before thermal shutdown or degradation |
| Dynamic Impedance (ZZ) | ≤10 Ω at IZ = 40 mA - ensures minimal voltage shift under dynamic load changes |
| Reverse Current (IR) | ≤20 μA at VR = 2.0 V - guarantees low leakage in standby or high-impedance sensing nodes |
| Temperature Coefficient (γZ) | −1.5 mV/°C - quantifies voltage drift per degree Celsius; enables compensation in precision analog designs |
| Surge Reverse Power (PRSM) | 400 W at t = 10 μs - supports transient suppression of short-duration ESD or inductive spikes |
| Junction Temperature (Tj) | 175°C maximum - constrains PCB layout and heatsinking for long-term reliability |
Pinout & Package
RD4.7F uses a DO-41 axial-leaded glass package (JEDEC standard) with cathode indicated by a black band. The device has two terminals: anode and cathode - no internal circuitry or control pins.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal | Connected to lower potential side in reverse-biased operation; carries forward current up to 200 mA |
| Cathode | Zener breakdown terminal | Marked with black band; connected to higher potential side during regulation; sinks zener current to ground or return rail |
Key Features
| Feature | Design Value |
|---|---|
| 1 W Planar Zener Structure | Enables stable, repeatable breakdown with low noise and predictable aging vs. diffused or alloy-junction alternatives |
| E24 Voltage Series Compliance | Supports standardized BOM consolidation across 2–82 V range without custom voltage bins |
| DHD (Double Heatsink Diode) Construction | Improves thermal dissipation via dual heat paths through leads and glass body, enhancing power handling at elevated ambient |
| B3 Grade Tight Tolerance | ±2.5% VZ tolerance (4.66–4.91 V) reduces need for post-production trimming in voltage reference circuits |
| Low −1.5 mV/°C Tempco | Minimizes drift in industrial-grade applications operating from −40°C to +125°C ambient |
Applications
| Power Supply Voltage Reference | Overvoltage Clamp in DC-DC Feedback |
|---|---|
Use Scenario: Providing stable 4.7 V reference for linear regulator error amplifiers or ADC reference buffers in embedded power modules. IC Role / Device Role / Timing Role: Two-terminal passive voltage reference establishing precise feedback threshold. Use Value: Enables ±1% output regulation accuracy with minimal external components and no active biasing required. |
Use Scenario: Clamping feedback node of buck converter IC to prevent runaway output during transient overload or startup fault. IC Role / Device Role / Timing Role: Fail-safe shunt element limiting sensed voltage to 4.7 V, protecting controller input pin. Use Value: Prevents erroneous high-duty-cycle response that could damage downstream loads or MOSFETs. |
| ESD Protection for Low-Voltage I/O | Waveform Limiting in Signal Conditioning |
Use Scenario: Protecting 3.3 V or 5 V microcontroller GPIO pins against contact ESD per IEC 61000-4-2 Level 3 (8 kV contact). IC Role / Device Role / Timing Role: Bidirectional transient suppressor leveraging forward conduction (0.7 V) and reverse zener action (4.7 V). Use Value: Absorbs 400 W surge energy within 10 μs without latch-up, preserving signal integrity and IC reliability. |
Use Scenario: Limiting audio or sensor signal swing to ±4.7 V in op-amp-based front-end stages to prevent amplifier saturation. IC Role / Device Role / Timing Role: Symmetric clipper when paired with inverted RD4.7F or used with series resistor for bidirectional clamping. Use Value: Maintains linearity in active filters and instrumentation amps while preventing rail-to-rail clipping distortion. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar zener voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4732A (ON Semiconductor) | Same 4.7 V nominal, but ±5% tolerance (4.47–4.94 V); higher ZZ = 14 Ω; DO-41 package | Less precise regulation; higher impedance limits use in high-dynamic-load references | Select when cost sensitivity outweighs tight VZ tolerance and low ZZ requirements |
| BZX55-C4V7 (Vishay) | 4.7 V nominal, ±5% tolerance; ZZ = 17 Ω; same DO-41 package; rated for 500 mW only | Lower power rating restricts continuous dissipation; unsuitable for >0.5 W sustained clamping | Choose only for low-power biasing or space-constrained legacy designs where 1 W rating is unnecessary |
Compared with RD4.7F, the 1N4732A offers broader availability but sacrifices regulation stability, while the BZX55-C4V7 trades power capability for smaller footprint - making RD4.7F optimal for industrial power supplies needing both precision and robustness.
Availability
RD4.7F is available at Aetrix Electronics and suitable for industrial power supplies, embedded voltage reference circuits, and ESD protection networks requiring stable component supply and long-lifecycle support.
Supply support for RD4.7F 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 leader formed in 2010 via merger of NEC Electronics and Renesas Technology, specializing in microcontrollers, analog, and power devices for industrial, automotive, and infrastructure markets.
The RD4.7F belongs to Renesas' legacy planar Zener diode family designed for general-purpose voltage regulation and transient suppression in "Standard"-grade applications including office equipment, test instruments, and industrial controls.
FAQ
What is the exact zener voltage tolerance for RD4.7F?
The RD4.7F is specified in B3 grade with a zener voltage range of 4.66 V to 4.91 V at IZ = 40 mA, corresponding to ±2.5% tolerance around the nominal 4.7 V value. This tighter binning supports precision reference applications without external trimming, and is confirmed in Renesas datasheet D13936EJ5V0DS, page 2.
Does RD4.7F support surge protection, and what is its peak pulse rating?
Yes, RD4.7F supports transient suppression with a surge reverse power rating of 400 W at pulse width t = 10 μs (non-repetitive), as specified in Absolute Maximum Ratings. This enables reliable clamping of ESD events and inductive switching spikes without failure, provided PCB layout minimizes parasitic inductance.
What is the thermal resistance of RD4.7F, and how does PCB copper area affect it?
RD4.7F's junction-to-ambient thermal resistance (RthJA) varies with PCB copper area: 200°C/W at 5 mm², 120°C/W at 10 mm², and 80°C/W at 20 mm² (per Figure 2 in datasheet). Designers must allocate adequate copper pour to sustain 1 W dissipation at elevated ambient temperatures.
Is RD4.7F RoHS compliant, and what is its lead finish?
RD4.7F meets EU RoHS Directive requirements, with lead finish specified as matte tin (Sn) per Renesas environmental compliance documentation. The device contains no lead, mercury, cadmium, hexavalent chromium, PBB, or PBDE above threshold limits, and is suitable for lead-free reflow assembly.
Can RD4.7F be used in place of a 5.1 V zener diode like RD5.1F?
No - RD4.7F is not a functional substitute for RD5.1F due to its distinct 4.7 V nominal zener voltage and associated B3-grade tolerance (4.66–4.91 V). Using RD4.7F where 5.1 V regulation is required would cause system-level undervoltage faults; voltage-specific selection is mandatory per application circuit requirements.
RD4.7F 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:
- -
RD4.7F FAQ
1.How can I place an order for RD4.7F through Aetrix?
Please submit a Request for Quotation (RFQ) for RD4.7F 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 RD4.7F reliable?
The price and inventory of RD4.7F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for RD4.7F is usually 5 days.
3.What payment methods are accepted for RD4.7F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for RD4.7F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for RD4.7F?
RD4.7F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your RD4.7F 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 RD4.7F?
For technical support, including RD4.7F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your RD4.7F requirements.
6.How does Aetrix verify that RD4.7F is sourced from the original manufacturer or authorized distributors?
All RD4.7F 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 RD4.7F meets industry standards.
7.What is the process for return or replacement of RD4.7F?
All RD4.7F units undergo pre-shipment inspection (PSI). If there is an issue with RD4.7F, 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 RD4.7F part is unused and in its original packaging.
Return procedure for RD4.7F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
RD4.7F Tags
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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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