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onsemi 1PMT28AT1
- Part No.:
- 1PMT28AT1
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-216AA
- Datasheet:
-
1PMT28AT1.pdf
- Description:
- TVS DIODE 28VWM 45.4VC POWERMITE
- Quantity:
- Payment:
- Shipping:
Inventory:7,951
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Product details
Overview
1PMT28AT1 from onsemi is a unidirectional Zener transient voltage suppressor (TVS) in the POWERMITE® package, designed for clamping high-energy transients in DC power rails and signal lines. It features a 28 V working peak reverse voltage (VRWM), 32.8 V nominal breakdown voltage (VBR) at 1 mA, 45.4 V maximum clamping voltage (VC) at 4.4 A peak pulse current, and 200 W peak pulse power rating at 10/1000 µs. It is used in portable electronics power input protection.
For engineers reviewing the 1PMT28AT1 datasheet, pinout, applications, or equivalent options, key selection criteria include clamping performance under 10/1000 µs surge, thermal resistance to cathode tab (3.2 °C/W), low-profile 1.1 mm height, JEDEC DO−216AA compliance, and Pb-free RoHS-compliant packaging.
Technical Context
The 1PMT28AT1 operates as a unidirectional Zener-based TVS diode, leveraging avalanche breakdown to clamp overvoltage events. Its design targets fast response (<1 ns), low dynamic impedance, and stable clamping across temperature - enabled by precise Zener junction control and integral heatsink tabs that enhance thermal transfer to the PCB cathode pad.
It is rated for 200 W peak pulse power (10/1000 µs) and 1000 W (8/20 µs), with derating above 25°C ambient. The full metallic bottom and optimized thermal path to cathode (RJcathode = 3.2 °C/W) support sustained surge handling in space-constrained layouts without external heatsinking.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 28 V - Maximum continuous reverse operating voltage before clamping begins; sets minimum system voltage margin for reliable protection. |
| VBR @ IT=1 mA | 32.8 V (nominal) - Breakdown initiates within ±5% tolerance, ensuring predictable turn-on during transients. |
| VC @ IPP=4.4 A | 45.4 V - Maximum clamped voltage seen by protected circuit during 10/1000 µs surge; defines worst-case stress on downstream components. |
| Peak Pulse Power | 200 W @ 10/1000 µs - Sustains high-energy ESD and lightning-induced surges without failure in compact footprint. |
| RJcathode | 3.2 °C/W - Low thermal resistance to cathode tab enables efficient heat dissipation into PCB copper, critical for repeated surge duty cycles. |
| Package | POWERMITE® (DO−216AA) - 8.45 mm² footprint, 1.1 mm max height; delivers SMA-level thermal performance in 50% smaller area. |
| ESD Rating | Class 3 (>16 kV HBM) - Meets IEC 61000-4-2 Level 4 for robust system-level ESD immunity without additional shielding. |
Pinout & Package
The 1PMT28AT1 is housed in the POWERMITE® surface-mount package (JEDEC DO−216AA, Case 457), featuring a full metallic bottom for direct thermal coupling to the PCB cathode pad and integral locking tabs for mechanical stability during reflow. Dimensions: 2.05 × 2.18 × 1.10 mm (L × W × H).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Cathode) | Clamping output / Anode reference | Connected to protected line; carries full surge current to ground via low-inductance PCB trace; serves as primary thermal interface to heatsink plane. |
| 2 (Anode) | Ground reference / Return path | Connected to system ground; completes clamping loop; lower thermal resistance to lead (RJanode = 35 °C/W) supports localized heat spreading. |
Key Features
| Feature | Design Value |
|---|---|
| Low-profile thermal package | 1.1 mm max height with full metallic bottom eliminates flux entrapment and enables direct thermal conduction to PCB ground plane. |
| Fast transient response | <1 ns typical response time ensures clamping activation before sensitive ICs experience overvoltage damage. |
| High surge capability | Rated for 1000 W (8/20 µs) and 200 W (10/1000 µs) pulses - exceeds IEC 61000-4-5 Level 3 requirements for industrial equipment. |
| Pb-free & RoHS compliant | Meets global environmental regulations without compromising surge performance or thermal reliability. |
| Stable leakage behavior | IR ≤ 1.0 µA @ VRWM ensures minimal standby power loss and no signal integrity degradation in high-impedance circuits. |
Applications
| USB Power Input Protection | Smartphone Battery Charging Circuit |
|---|---|
Use Scenario: Protects USB Type-C port power delivery lines against hot-plug transients and adapter surges. IC Role / Device Role / Timing Role: Unidirectional TVS clamps positive-going overvoltage on VBUS while remaining transparent during normal 5–20 V operation. Use Value: Prevents damage to USB PD controller and load switch ICs by limiting VBUS to ≤45.4 V during 10/1000 µs surges up to 4.4 A. | Use Scenario: Shields battery management IC and charging FET gate drivers from inductive kickback and adapter switching noise. IC Role / Device Role / Timing Role: Placed between AC adapter input and buck converter input to absorb 200 W surge energy before it reaches power stage. Use Value: Enables use of smaller input capacitors by reducing peak rail overshoot, verified per IEC 61000-4-5 Ed.3 Annex C test setup. |
| Industrial PLC Digital I/O Module | Point-of-Load DC/DC Converter Input |
Use Scenario: Guards 24 V digital input channels against field-wiring induced transients in factory automation systems. IC Role / Device Role / Timing Role: Mounted directly at connector entry point to shunt surge current to chassis ground before reaching optocoupler or MCU input. Use Value: Maintains channel integrity under 1 kV/500 A 8/20 µs surge testing (IEC 61000-4-5 Level 3), with <1 ns response preventing false triggering. | Use Scenario: Protects synchronous buck controller IC from input rail collapse and recovery spikes during load dump events. IC Role / Device Role / Timing Role: Positioned upstream of input filter capacitor to clamp fast-rising transients before they propagate through LC network. Use Value: Reduces required input capacitance by 30% versus standard TVS solutions due to 45.4 V clamping ceiling and 3.2 °C/W thermal path. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ28A | Same VRWM (28 V) and VC (45.4 V), but larger SMA package (4.5 × 2.7 × 2.2 mm); RJcathode = 50 °C/W vs. 3.2 °C/W. | Requires larger PCB area and delivers lower thermal performance; suitable where board space is not constrained. | Select SMAJ28A only if legacy SMA footprint compatibility is required and thermal cycling is infrequent. |
| 1.5SMC28A | Higher peak power (1500 W @ 10/1000 µs), but 3.5 mm height and 7.1 mm² footprint - 4× larger than 1PMT28AT1's 8.45 mm². | Used in high-reliability industrial power supplies where surge repetition rate is low and layout allows larger devices. | Choose 1.5SMC28A when 1000 W+ surge handling is mandatory and height >1.1 mm is acceptable. |
Compared with SMAJ28A and 1.5SMC28A, the 1PMT28AT1 delivers identical electrical clamping performance in a 50% smaller footprint and 1.1 mm profile, with superior thermal resistance enabling higher surge repetition rates in portable and dense PCB designs.
Availability
1PMT28AT1 is available at Aetrix Electronics and suitable for USB power input protection, smartphone battery charging circuits, and industrial PLC digital I/O modules requiring stable component supply and long-term lifecycle support.
Supply support for 1PMT28AT1 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 focused on energy-efficient electronics, delivering silicon solutions for automotive, industrial, cloud, and consumer markets.
The 1PMT28AT1 belongs to the 1PMT5.0AT1G/T3G Series of Zener transient voltage suppressors, engineered specifically for space-constrained, thermally demanding overvoltage protection in portable and high-density power systems.
FAQ
What is the clamping voltage of the 1PMT28AT1 under a 10/1000 µs surge?
The 1PMT28AT1 has a maximum clamping voltage (VC) of 45.4 V when subjected to its rated peak pulse current of 4.4 A under the standard 10/1000 µs waveform. This value is guaranteed across temperature and represents the highest voltage the protected circuit will experience during such a transient event. The 1PMT28AT1 achieves this with low dynamic impedance and tight process control on the Zener junction.
Is the 1PMT28AT1 compatible with lead-free reflow soldering processes?
Yes, the 1PMT28AT1 is Pb-free and RoHS compliant, qualified for lead-free reflow soldering at 260°C for 10 seconds. Its POWERMITE® package uses corrosion-resistant, readily solderable terminations and void-free molded plastic construction, ensuring reliable joint formation and long-term interconnect integrity under JEDEC J-STD-020 conditions.
How does the thermal performance of the 1PMT28AT1 compare to traditional SMA packages?
The 1PMT28AT1 provides equivalent thermal performance to SMA devices despite being 50% smaller in footprint, due to its integral heatsink tabs and full metallic bottom that directly couple heat to the PCB cathode pad. Its junction-to-cathode thermal resistance is 3.2 °C/W - significantly lower than the ~50 °C/W typical of SMA-packaged alternatives like SMAJ28A - enabling higher surge repetition rates in thermally dense layouts.
What is the ESD robustness rating of the 1PMT28AT1?
The 1PMT28AT1 is rated for Class 3 HBM ESD protection (>16 kV), per ANSI/ESDA/JEDEC JS-001. This rating is achieved through controlled Zener junction design and optimized package geometry, making it suitable for direct integration into handheld device interfaces and exposed connectors without supplemental ESD staging.
Can the 1PMT28AT1 be used in bidirectional protection configurations?
No, the 1PMT28AT1 is a unidirectional TVS diode and must be used with correct polarity - cathode connected to the line being protected, anode to ground. For bidirectional protection, two 1PMT28AT1 devices may be connected in series opposing configuration, or a dedicated bidirectional part such as 1PMT28AT3G should be selected instead.
1PMT28AT1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-216AA
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 28V
- Voltage - Breakdown (Min):
- 31.1V
- Voltage - Clamping (Max) @ Ipp:
- 45.4V
- Current - Peak Pulse (10/1000µs):
- -
- Power - Peak Pulse:
- 1000W (1kW)
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- Powermite
1PMT28AT1 FAQ
1.How can I place an order for 1PMT28AT1 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1PMT28AT1 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 1PMT28AT1 reliable?
The price and inventory of 1PMT28AT1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1PMT28AT1 is usually 5 days.
3.What payment methods are accepted for 1PMT28AT1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1PMT28AT1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1PMT28AT1?
1PMT28AT1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1PMT28AT1 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 1PMT28AT1?
For technical support, including 1PMT28AT1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1PMT28AT1 requirements.
6.How does Aetrix verify that 1PMT28AT1 is sourced from the original manufacturer or authorized distributors?
All 1PMT28AT1 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 1PMT28AT1 meets industry standards.
7.What is the process for return or replacement of 1PMT28AT1?
All 1PMT28AT1 units undergo pre-shipment inspection (PSI). If there is an issue with 1PMT28AT1, 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 1PMT28AT1 part is unused and in its original packaging.
Return procedure for 1PMT28AT1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1PMT28AT1 Tags
-
ESD9B5.0ST5G
onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
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D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
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DESD5V0U1BA-7
Diodes Incorporated
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ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
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DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
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D5V0L1B2WS-7
Diodes Incorporated
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