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Microchip Technology 1PMT5939B/TR7
- Part No.:
- 1PMT5939B/TR7
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-216AA
- Datasheet:
-
1PMT5939B/TR7.pdf
- Description:
- DIODE ZENER 39V 3W DO216AA
- Quantity:
- Payment:
- Shipping:
Inventory:7,540
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Product details
Overview
1PMT5939B/TR7 from Microsemi is a 39 V, ±5% tolerance surface-mount Zener diode in the Powermite® package, rated for 3.0 W DC power dissipation at TAB 1 = 60°C, with 45 Ω dynamic impedance at 9.6 mA test current and 900 µA max reverse leakage at 29.7 V. It serves as a precision voltage reference or overvoltage clamp in DC power rails and regulator feedback paths.
For engineers reviewing the 1PMT5939B/TR7 datasheet, 1PMT5939B/TR7 pinout, 1PMT5939B/TR7 application, or 1PMT5939B/TR7 equivalent, key selection criteria include zener voltage tolerance, thermal resistance (30°C/W junction-to-TAB), ESD rating (>16 kV HBM), low knee impedance (0.25 Ω), and compatibility with EIA-481 tape-and-reel automated assembly.
Technical Context
This Zener diode operates in reverse breakdown mode with a nominal zener voltage of 39 V at 9.6 mA (IZT), exhibiting 45 Ω dynamic impedance (ZZT) and 0.25 Ω knee impedance (ZZK) at 0.25 mA (IZK). Its thermal resistance of 30°C/W from junction to TAB 1 enables stable regulation under sustained 3.0 W power dissipation when mounted on thermally adequate PCB copper.
The Powermite® package features a full metallic bottom (eliminating solder flux entrapment) and an integral locking tab acting as a heat sink, supporting automatic insertion equipment and enabling direct thermal conduction from the die to the PCB mounting pad via TAB 1 - designated as cathode.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 39 V ±5% at IZT = 9.6 mA - defines stable regulation point for feedback or clamping circuits |
| Power Dissipation | 3.0 W at TAB 1 = 60°C - sets maximum continuous DC power handling with thermal derating above 60°C |
| Dynamic Impedance | 45 Ω at IZT - determines output voltage variation under load current changes |
| Knee Impedance | 0.25 Ω at IZK = 0.25 mA - ensures stable low-current regulation near breakdown threshold |
| Reverse Leakage | 900 µA max at VR = 29.7 V - limits standby power loss in high-impedance bias networks |
| Thermal Resistance | 30°C/W junction-to-TAB 1 - quantifies temperature rise per watt, critical for thermal design on PCB |
| ESD Rating | >16 kV per HBM - provides robustness against handling and board-level electrostatic discharge events |
Pinout & Package
Package: Powermite® (DO-216AA), molded surface-mount package with full metallic bottom and integral heat-sink locking tab; cathode designated by TAB 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| TAB 1 | Cathode | Primary thermal path and electrical cathode connection; must be soldered to copper pour for thermal management |
| Lead 2 | Anode | Standard anode terminal; electrically isolated from TAB 1; used for circuit connection |
Key Features
| Feature | Design Value |
|---|---|
| Surface-mount Powermite® package | Enables automated placement and reflow while delivering 3.0 W power handling in footprint smaller than DO-41 |
| Integral heat-sink locking tab | TAB 1 acts as both cathode and primary thermal interface, reducing junction-to-PCB thermal resistance |
| Full metallic bottom | Prevents solder flux entrapment during reflow, eliminating post-assembly cleaning and reliability risks |
| ESD robustness | >16 kV HBM rating allows safe handling and operation in unshielded industrial environments |
Applications
| DC Power Supply Regulation | Overvoltage Protection Circuit |
|---|---|
Use Scenario: Stabilizing feedback voltage in isolated flyback or buck converter secondary-side regulation. IC Role / Device Role / Timing Role: Precision shunt reference providing stable 39 V reference to optocoupler or TL431 input. Use Value: Tight 5% VZ tolerance and low ZZT (45 Ω) minimize output voltage drift across line/load/temperature. | Use Scenario: Clamping transient surges on 36 V automotive or industrial control bus lines. IC Role / Device Role / Timing Role: Fast-acting shunt protector diverting excess energy to ground before downstream ICs are damaged. Use Value: 3.0 W power rating and 30°C/W thermal resistance allow sustained clamping without thermal runaway. |
| Programmable Voltage Reference | Current Source Bias Network |
Use Scenario: Setting precise bias points in analog sensor signal conditioning stages requiring stable 39 V rail. IC Role / Device Role / Timing Role: Two-terminal voltage reference establishing fixed node for op-amp biasing or DAC reference scaling. Use Value: Low knee impedance (0.25 Ω) ensures regulation stability even at microamp-level quiescent currents. | Use Scenario: Generating constant current for LED driver or laser diode bias using resistor-Zener topology. IC Role / Device Role / Timing Role: Stable voltage source enabling predictable current setpoint via series resistor. Use Value: 900 µA max IR at 29.7 V minimizes error in low-current applications where leakage dominates setpoint accuracy. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMCJ39A | TVS diode (not Zener); 39 V standoff, 600 W peak pulse power, higher clamping voltage (60.3 V) | Designed for transient suppression, not precision regulation | Select only for surge protection; not suitable as voltage reference due to wide clamping vs. breakdown spread |
| BZX84-C39 | SOT-23 package; 39 V ±5%, 300 mW power rating, 90 Ω ZZT at 5 mA | Limited thermal capacity; unsuitable for >300 mW continuous dissipation | Use only in low-power signal-level references; requires PCB thermal relief reduction for 1PMT5939B/TR7's 3.0 W capability |
Compared with SMCJ39A and BZX84-C39, the 1PMT5939B/TR7 delivers true Zener regulation at 3.0 W with verified 45 Ω impedance and 30°C/W thermal resistance - making it uniquely suited for high-stability, high-power shunt reference and clamping roles where precision and thermal performance are co-critical.
Availability
1PMT5939B/TR7 is available at Aetrix Electronics and suitable for DC power supply regulation, overvoltage protection circuits, and programmable voltage reference designs requiring stable component supply and traceable sourcing.
Supply support for 1PMT5939B/TR7 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 semiconductor manufacturer specializing in high-reliability analog, mixed-signal, and radiation-hardened components for aerospace, defense, and industrial markets.
The Powermite® Zener diode product line (1PMT59xxB series) was designed for surface-mount power regulation and protection in space-constrained, thermally demanding applications where traditional through-hole Zeners fall short.
FAQ
What is the zener voltage tolerance for 1PMT5939B/TR7?
The 1PMT5939B/TR7 has a standard zener voltage tolerance of ±5% at 39 V, measured at IZT = 9.6 mA with TAB 1 held at 30°C. Tighter tolerances (±2% and ±1%) are available with suffixes C and D respectively, but the base 1PMT5939B/TR7 part uses the ±5% grade. This tolerance directly impacts regulation accuracy in feedback loops and reference networks.
How is thermal management handled for 1PMT5939B/TR7 in PCB layout?
Thermal management for 1PMT5939B/TR7 relies on TAB 1 - the cathode terminal - which serves as the primary thermal path. The device's 30°C/W junction-to-TAB thermal resistance requires direct soldering of TAB 1 to a minimum 100 mm² copper pour with ≥2 thermal vias to internal ground planes. Without this, the 3.0 W rating cannot be sustained beyond brief pulses.
Is 1PMT5939B/TR7 compatible with lead-free reflow processes?
Yes, the 1PMT5939B/TR7 Powermite® package is qualified for standard lead-free reflow profiles (JEDEC J-STD-020), including peak temperatures up to 260°C. Its molded construction and metallic bottom ensure mechanical integrity and flux exclusion during reflow, eliminating voiding or delamination risks common in alternative SMD Zener packages.
What does the "TR7" suffix indicate in 1PMT5939B/TR7?
The "TR7" suffix denotes tape-and-reel packaging per EIA-481 standard, with 3,000 units per 7-inch reel. This format supports automated pick-and-place assembly and is the standard shipping configuration for the 1PMT5939B/TR7. No electrical or thermal differences exist between TR7 and bulk or other reel variants - only packaging and quantity differ.
Can 1PMT5939B/TR7 be used as a replacement for through-hole 1N5939B?
While 1PMT5939B/TR7 shares identical electrical specifications (39 V, ±5%, 3.0 W) with the through-hole 1N5939B, it is not a drop-in replacement due to different package (Powermite® DO-216AA vs. DO-41) and pinout (TAB 1 cathode vs. axial leads). PCB redesign is required to accommodate the surface-mount footprint and thermal pad layout - though system-level function remains equivalent.
1PMT5939B/TR7 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-216AA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 39 V
- Tolerance:
- ±5%
- Power - Max:
- 3 W
- Impedance (Max) (Zzt):
- 45 Ohms
- Current - Reverse Leakage @ Vr:
- 1 µA @ 29.7 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-216AA
1PMT5939B/TR7 FAQ
1.How can I place an order for 1PMT5939B/TR7 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1PMT5939B/TR7 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 1PMT5939B/TR7 reliable?
The price and inventory of 1PMT5939B/TR7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1PMT5939B/TR7 is usually 5 days.
3.What payment methods are accepted for 1PMT5939B/TR7?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1PMT5939B/TR7 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1PMT5939B/TR7?
1PMT5939B/TR7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1PMT5939B/TR7 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 1PMT5939B/TR7?
For technical support, including 1PMT5939B/TR7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1PMT5939B/TR7 requirements.
6.How does Aetrix verify that 1PMT5939B/TR7 is sourced from the original manufacturer or authorized distributors?
All 1PMT5939B/TR7 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 1PMT5939B/TR7 meets industry standards.
7.What is the process for return or replacement of 1PMT5939B/TR7?
All 1PMT5939B/TR7 units undergo pre-shipment inspection (PSI). If there is an issue with 1PMT5939B/TR7, 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 1PMT5939B/TR7 part is unused and in its original packaging.
Return procedure for 1PMT5939B/TR7:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1PMT5939B/TR7 Tags
-
MMBZ5240B-7-F
Diodes Incorporated
-
BZT52C5V6T-7
Diodes Incorporated
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MMSZ5231B-7-F
Diodes Incorporated
-
BZT52C15-7-F
Diodes Incorporated
-
BZX84C3V3LT1G
onsemi
-
MMSZ5245BS-7-F
Diodes Incorporated
-
MMSZ4682T1G
onsemi
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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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