My Inquiry
My Account
Diodes Incorporated DFLT28A-7
- Part No.:
- DFLT28A-7
- Manufacturer:
- Diodes Incorporated
- Category:
- TVS Diodes
- Package:
- POWERDI®123
- Datasheet:
-
DFLT28A-7.pdf
- Description:
- TVS DIODE 28VWM 45.4VC PWRDI 123
- Quantity:
- Payment:
- Shipping:
Inventory:2,775
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
DFLT28A-7 from Diodes Incorporated is a unidirectional transient voltage suppressor (TVS) diode in PowerDI123 package, designed for primary overvoltage protection of DC power rails and signal lines. It features 28 V reverse standoff voltage (VRWM), 31.1–34.4 V breakdown voltage (VBR), 45.4 V clamping voltage (VC) at 4.96 A peak pulse current (IPP), and 225 W peak pulse power dissipation (10/1000 µs waveform). It is used in automotive infotainment power inputs to suppress load dump and ISO 7637-2 transients.
For engineers reviewing the DFLT28A-7 datasheet, DFLT28A-7 pinout, DFLT28A-7 application, or DFLT28A-7 equivalent, key selection criteria include clamping voltage margin relative to protected IC's absolute maximum rating, thermal resistance (RθJS = 6 °C/W), IEC 61000-4-5 surge capability, and compatibility with automated SMT assembly on FR-4 PCBs with 2 oz copper pads.
Technical Context
This TVS operates as a unidirectional avalanche diode, triggered when reverse voltage exceeds VRWM = 28 V and fully clamping at VC = 45.4 V under 4.96 A IPP (10/1000 µs). Its low RθJS = 6 °C/W enables effective heat transfer from junction to cathode tab, supporting sustained surge handling in compact layouts.
It exhibits <1.0 µA reverse leakage at VRWM, ensuring minimal standby power loss, and maintains stable clamping performance across –65 °C to +150 °C operating temperature range. The device is rated for 50 A non-repetitive forward surge current (IFSM), suitable for high-energy transient suppression in 12 V automotive systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reverse Standoff Voltage (VRWM) | 28 V - Maximum continuous DC voltage before significant leakage; sets upper limit for protected circuit's normal operating voltage. |
| Breakdown Voltage (VBR) | 31.1–34.4 V @ 1.0 mA - Voltage at which avalanche conduction begins; defines turn-on threshold with ±5.3% tolerance. |
| Clamping Voltage (VC) | 45.4 V @ 4.96 A IPP - Maximum voltage seen by downstream circuit during 10/1000 µs surge; must stay below IC's absolute max rating. |
| Peak Pulse Power (PPK) | 225 W (10/1000 µs) - Surge energy-handling capacity; determines survivability against ISO 7637-2 Pulse 5a load dump events. |
| Thermal Resistance (RθJS) | 6 °C/W - Junction-to-solder-joint thermal resistance; enables efficient heat extraction via cathode tab to PCB copper pour. |
| Operating Temperature | –65 °C to +150 °C - Full automotive-grade range; supports under-hood and infotainment module deployment without derating. |
Pinout & Package
Package: PowerDI123 - surface-mount, single-diode configuration with cathode band marking; molded green plastic (UL 94V-0), 0.01 g mass, matte tin annealed terminals.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Input/Line side terminal | Connected to protected line (e.g., 12 V supply rail); carries surge current into device during clamping. |
| Cathode | Output/Ground reference terminal | Connected to system ground or low-impedance return path; serves as primary thermal interface to PCB copper pad. |
Key Features
| Feature | Design Value |
|---|---|
| 225 W peak pulse power (10/1000 µs) | Enables robust protection against automotive load dump (ISO 7637-2 Pulse 5a) without external heatsinking. |
| RθJS = 6 °C/W | Allows >80% of surge energy to be conducted directly from die to PCB ground plane, reducing thermal stress on bond wires. |
| Lead-free, halogen-free, RoHS 3 compliant | Meets automotive OEM environmental requirements (J-STD-020 Level 1 moisture sensitivity, IATF 16949 manufacturing). |
| Cathode band polarity marking | Ensures correct orientation during automated placement; prevents reverse-bias failure during ESD or surge events. |
Applications
| Automotive Body Control Module (BCM) | Industrial PLC Digital Input |
|---|---|
Use Scenario: Protects 12 V power input of BCM microcontroller and CAN transceiver from battery load dump and jump-start surges. IC Role / Device Role: Primary unidirectional TVS clamp placed upstream of LDO regulator and ESD protection array. Use Value: Limits transient voltage to ≤45.4 V, preserving MCU and transceiver integrity while maintaining <1 µA leakage during normal operation. |
Use Scenario: Shields 24 V digital input channel of PLC I/O module from field-wiring induced surges and inductive kickback. IC Role / Device Role: Front-end overvoltage guard before optocoupler input and series current-limiting resistor. Use Value: Clamps 1 kV/500 A surge (IEC 61000-4-5) within 1 ns, preventing latch-up or gate oxide damage in input conditioning circuitry. |
| Automotive Infotainment Power Rail | Telecom PoE Midspan Interface |
Use Scenario: Secures 5 V/3.3 V DC-DC converter input in head unit against reverse battery connection and alternator ripple spikes. IC Role / Device Role: Secondary TVS stage after fuse and common-mode choke; coordinates with upstream polymer PTC. Use Value: Provides <10 ns response time and 45.4 V clamping to keep downstream buck controller within 6 V absolute max rating. |
Use Scenario: Protects 48 V PoE midspan data port from Ethernet cable ESD (IEC 61000-4-2) and lightning-induced longitudinal surges. IC Role / Device Role: Unidirectional clamp on power pair (PSE side), paired with bidirectional TVS on data lines. Use Value: Delivers 225 W surge handling with 0.01 g mass-enabling dense port count without thermal crowding on midspan PCB. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ28A (Bourns) | Same VRWM (28 V), but higher VC = 48.4 V @ 4.65 A IPP; SMA package (RθJA = 140 °C/W vs. DFLT28A-7's RθJS = 6 °C/W). | Limited to lower-duty-cycle surges due to higher thermal resistance; unsuitable for repeated load dump events without board-level heatsinking. | Select when cost is prioritized over thermal performance and surge repetition rate is low. |
| TPSMD28 (Texas Instruments) | Identical VRWM and VC (45.4 V), but rated for 300 W (10/1000 µs); larger SMD-2 package (RθJS ≈ 4.5 °C/W), lead-free only (no halogen-free claim). | Better surge margin for harsh environments (e.g., commercial vehicle alternators), but requires larger PCB footprint and lacks "Green" certification. | Select when peak power margin >33% is required and halogen-free compliance is not mandated. |
Compared with SMAJ28A and TPSMD28, DFLT28A-7 delivers optimal balance of low clamping voltage, ultra-low thermal resistance, and full automotive environmental compliance in the smallest footprint-making it preferred for space-constrained, high-reliability 12 V systems.
Availability
DFLT28A-7 is available at Aetrix Electronics and suitable for automotive body control modules, industrial PLC digital inputs, and telecom PoE midspan interfaces requiring stable component supply, long-term lifecycle support, and AEC-Q-compliant sourcing traceability.
Supply support for DFLT28A-7 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
Diodes Incorporated is a global semiconductor company specializing in discrete, analog, and mixed-signal solutions, with design, manufacturing, and test facilities certified to IATF 16949 and ISO 9001 standards.
DFLT28A-7 belongs to the DFLTxxxA series of high-power unidirectional TVS diodes engineered specifically for automotive and industrial power rail protection, emphasizing low clamping voltage, fast response, and robust thermal performance in compact packages.
FAQ
What is the maximum clamping voltage of DFLT28A-7 under standard test conditions?
The maximum clamping voltage (VC) is 45.4 V, measured at 4.96 A peak pulse current using the 10/1000 µs waveform per IEC 61000-4-5. This value is guaranteed across –65 °C to +150 °C and represents the highest voltage imposed on protected circuitry during worst-case surge events.
Can DFLT28A-7 be used in bidirectional protection configurations?
No-DFLT28A-7 is a unidirectional TVS diode intended for DC power line protection where polarity is fixed. For AC or bidirectional signal line protection, Diodes offers the DFLSxxA series (e.g., DFLS28A), which uses a back-to-back diode configuration to handle both polarities.
What is the recommended PCB pad layout for optimal thermal performance?
Use the PowerDI123 suggested pad layout from Diodes' package outline document: 2.40 mm × 4.10 mm thermal pad (X1 × X2), with 1.50 mm solder mask opening (Y × Y1), and ≥1 inch² of 2 oz copper connected directly to the cathode terminal. This achieves the specified RθJS = 6 °C/W and prevents thermal runaway during repetitive surges.
Is DFLT28A-7 qualified to AEC-Q101 for automotive use?
DFLT28A-7 is not AEC-Q101 qualified; the automotive-qualified version is DFLT28AQ, documented separately under DS30581Q. DFLT28A-7 meets all electrical and mechanical specifications of the Q-grade part but lacks PPAP documentation and extended reliability testing required for automotive safety-critical applications.
DFLT28A-7 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Package/Case:
- POWERDI®123
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- 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):
- 4.96A
- Power - Peak Pulse:
- 225W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- PowerDI™ 123
DFLT28A-7 FAQ
1.How can I place an order for DFLT28A-7 through Aetrix?
Please submit a Request for Quotation (RFQ) for DFLT28A-7 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 DFLT28A-7 reliable?
The price and inventory of DFLT28A-7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for DFLT28A-7 is usually 5 days.
3.What payment methods are accepted for DFLT28A-7?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for DFLT28A-7 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for DFLT28A-7?
DFLT28A-7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your DFLT28A-7 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 DFLT28A-7?
For technical support, including DFLT28A-7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your DFLT28A-7 requirements.
6.How does Aetrix verify that DFLT28A-7 is sourced from the original manufacturer or authorized distributors?
All DFLT28A-7 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 DFLT28A-7 meets industry standards.
7.What is the process for return or replacement of DFLT28A-7?
All DFLT28A-7 units undergo pre-shipment inspection (PSI). If there is an issue with DFLT28A-7, 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 DFLT28A-7 part is unused and in its original packaging.
Return procedure for DFLT28A-7:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
DFLT28A-7 Tags
-
ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
-
D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
-
DESD5V0U1BA-7
Diodes Incorporated
-
ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
-
D5V0L1B2WS-7
Diodes Incorporated
Tech Hub
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…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
