My Inquiry
My Account
Microchip Technology SMAJ4756E3/TR13
- Part No.:
- SMAJ4756E3/TR13
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ4756E3/TR13.pdf
- Description:
- DIODE ZENER 47V 2W DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:7,522
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMAJ4756E3/TR13 from Microsemi (now Microchip Technology) is a 2 W surface-mount silicon Zener diode with a nominal zener voltage of 47 V ±5%, 5.5 mA test current, 80 Ω dynamic impedance at IZT, and 35.8 V minimum knee voltage. It provides precise voltage regulation in power supply feedback loops and overvoltage protection circuits for industrial DC-DC converters.
For engineers reviewing the SMAJ4756E3/TR13 datasheet, SMAJ4756E3/TR13 pinout, SMAJ4756E3/TR13 application, or SMAJ4756E3/TR13 equivalent, key selection criteria include its DO-214AC package compatibility, 1500 mA peak surge current rating, -55°C to +150°C operating temperature range, and JEDEC 1N4756A electrical equivalence.
Technical Context
This Zener diode operates in reverse breakdown mode to maintain stable reference voltage under varying load and line conditions. Its 47 V nominal zener voltage is specified at 5.5 mA test current with 80 Ω dynamic impedance, ensuring low regulation error across moderate current variations.
The device features a sharp breakdown knee (ZZK = 1500 Ω at IZK = 0.25 mA), enabling reliable clamping during transient overvoltage events. Thermal resistance of 25°C/W (junction-to-lead) supports sustained 2 W power dissipation when mounted on 4.0 mm² copper pads per terminal.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 47 V ±5% - defines regulated output voltage in shunt regulator or clamp circuits |
| Test Current (IZT) | 5.5 mA - bias point where VZ and ZZT are guaranteed |
| Dynamic Impedance (ZZT) | 80 Ω - determines regulation sensitivity to current changes near IZT |
| Peak Surge Current (IS) | 95 mA - maximum non-repetitive transient current it can safely clamp |
| Steady-State Power (PAV) | 2.0 W - continuous dissipation limit with proper PCB thermal design |
| Operating Temperature | -55°C to +150°C - supports use in automotive engine compartments and industrial enclosures |
| Knee Voltage (VZK) | 35.8 V - minimum voltage at which regulation begins (at IZK = 0.25 mA) |
Pinout & Package
DO-214AC (SMAJ) surface-mount package with cathode band marking polarity. Two-terminal device: anode and cathode.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal in forward bias; connected to lower potential in Zener operation | Must be routed to circuit ground or lowest reference node in shunt regulator configuration |
| Cathode | Current exit terminal in forward bias; connected to higher potential in Zener operation | Marked by band; connects to regulated rail or protected node requiring voltage clamping |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC 1N4756A equivalence | Electrically identical to through-hole 1N4756A - enables drop-in replacement in legacy designs with SMT conversion |
| High surge current rating | 95 mA peak (½-sine, 1/120 s) - withstands common ESD and inductive switching transients without degradation |
| Thermal performance | RθJL = 25°C/W with 4.0 mm² copper pads - allows full 2 W operation up to 100°C ambient before derating |
| Surface-mount handling | Flat side for accurate pick-and-place - ensures consistent orientation and solder joint reliability in automated assembly |
Applications
| Industrial Power Supply Feedback | Automotive Load Dump Protection |
|---|---|
Use Scenario: Regulating output voltage in isolated flyback or forward converter secondary-side feedback networks. IC Role / Device Role / Timing Role: Shunt voltage reference providing stable 47 V reference to optocoupler input or TL431 comparator. Use Value: Maintains ±5% output regulation across line/load variations due to tight VZ tolerance and low ZZT. | Use Scenario: Clamping induced transients during battery disconnect in 12 V automotive systems. IC Role / Device Role / Timing Role: Transient voltage suppressor placed across motor driver inputs or ECU power rails. Use Value: Limits voltage spikes to ≤47 V with 95 mA surge capability, protecting downstream MOSFETs and logic ICs. |
| DC-DC Converter Overvoltage Clamp | Programmable Reference Generator |
Use Scenario: Safeguarding buck converter outputs against runaway feedback failure or controller fault. IC Role / Device Role / Timing Role: Secondary-stage Zener clamp activated only during overvoltage faults above 47 V. Use Value: Prevents damage to connected loads by limiting max output to 47 V while dissipating up to 2 W continuously. | Use Scenario: Building precision voltage references using series/parallel Zener configurations. IC Role / Device Role / Timing Role: Primary 47 V reference element in multi-Zener divider networks for programmable supply setpoints. Use Value: Enables stable 47 V node with <80 Ω AC impedance, supporting low-drift reference generation for ADCs and DACs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4756A | Through-hole DO-41 package; identical electrical specs (47 V, 5.5 mA, 80 Ω ZZT) | Requires PCB redesign for through-hole mounting; no SMT compatibility | Select when legacy through-hole assembly is mandatory and board space permits larger footprint |
| BZX84-C47 | SOT-23 package; 47 V ±5%, but lower 300 mW power rating and 100 mA surge limit | Not suitable for 2 W continuous or high-energy transient suppression | Choose only for low-power signal-level referencing where thermal constraints prohibit SMAJ package |
Compared with 1N4756A and BZX84-C47, SMAJ4756E3/TR13 delivers full 2 W power handling and SMT manufacturability in DO-214AC, making it optimal for high-reliability industrial power rails where both robustness and automated assembly are required.
Availability
SMAJ4756E3/TR13 is available at Aetrix Electronics and suitable for industrial power supplies, automotive electronics, DC-DC converter protection, and programmable reference circuits requiring stable component supply and long-term obsolescence management.
Supply support for SMAJ4756E3/TR13 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 (acquired by Microchip Technology in 2018) is a U.S.-based semiconductor company specializing in high-reliability analog, mixed-signal, and radiation-hardened components.
The SMAJ47xxA series was designed for surface-mount voltage regulation and transient suppression in harsh-environment power systems, emphasizing thermal robustness, JEDEC compatibility, and high-surge survivability.
FAQ
What is the zener voltage tolerance for SMAJ4756E3/TR13?
SMAJ4756E3/TR13 has a nominal zener voltage of 47 V with a tolerance of ±5%, as indicated by the absence of a tolerance suffix (e.g., 'C' for 2% or 'D' for 1%). This tolerance applies under standard test conditions at 25°C with 5.5 mA test current, and is confirmed in the Electrical Characteristics table of the official Microchip datasheet MSC0284A.
Is SMAJ4756E3/TR13 compatible with the through-hole 1N4756A?
Yes, SMAJ4756E3/TR13 is electrically equivalent to JEDEC-registered 1N4756A, sharing identical zener voltage (47 V), test current (5.5 mA), dynamic impedance (80 Ω), and knee voltage (35.8 V). The primary difference is packaging: SMAJ4756E3/TR13 uses DO-214AC for surface mount, while 1N4756A uses DO-41 for through-hole assembly.
What is the maximum steady-state power dissipation for SMAJ4756E3/TR13?
The maximum steady-state power dissipation for SMAJ4756E3/TR13 is 2.0 W at 25°C ambient, measured with the device mounted on 4.0 mm² copper pads per terminal. Power must be linearly derated above 100°C lead temperature, reaching zero at 150°C, per Note 3 in the Maximum Ratings table of the datasheet.
How is polarity marked on SMAJ4756E3/TR13?
Polarity on SMAJ4756E3/TR13 is indicated by a cathode band printed on the body of the DO-214AC package. The banded end corresponds to the cathode terminal, which must be connected to the higher-potential node in Zener regulation or clamping applications. This marking aligns with JEDEC DO-214AC mechanical standards and is visible under standard optical inspection.
What is the peak surge current rating for SMAJ4756E3/TR13?
SMAJ4756E3/TR13 has a peak surge current rating of 95 mA, measured using a ½-sine wave pulse of 1/120 second duration at 25°C ambient. This rating reflects its ability to absorb single-event transients such as inductive kickback or ESD without parametric shift or failure, as defined in Note 3 of the Electrical Characteristics table.
SMAJ4756E3/TR13 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-214AC, SMA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Voltage - Zener (Nom) (Vz):
- 47 V
- Tolerance:
- ±10%
- Power - Max:
- 2 W
- Impedance (Max) (Zzt):
- 80 Ohms
- Current - Reverse Leakage @ Vr:
- 5 µA @ 35.8 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 200 mA
- Operating Temperature:
- -55°C ~ 150°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AC
SMAJ4756E3/TR13 FAQ
1.How can I place an order for SMAJ4756E3/TR13 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ4756E3/TR13 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 SMAJ4756E3/TR13 reliable?
The price and inventory of SMAJ4756E3/TR13 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ4756E3/TR13 is usually 5 days.
3.What payment methods are accepted for SMAJ4756E3/TR13?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ4756E3/TR13 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ4756E3/TR13?
SMAJ4756E3/TR13 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ4756E3/TR13 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 SMAJ4756E3/TR13?
For technical support, including SMAJ4756E3/TR13 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ4756E3/TR13 requirements.
6.How does Aetrix verify that SMAJ4756E3/TR13 is sourced from the original manufacturer or authorized distributors?
All SMAJ4756E3/TR13 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 SMAJ4756E3/TR13 meets industry standards.
7.What is the process for return or replacement of SMAJ4756E3/TR13?
All SMAJ4756E3/TR13 units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ4756E3/TR13, 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 SMAJ4756E3/TR13 part is unused and in its original packaging.
Return procedure for SMAJ4756E3/TR13:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ4756E3/TR13 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
Tech Hub
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
