My Inquiry
My Account
STMicroelectronics SMBJ170A-TR
- Part No.:
- SMBJ170A-TR
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMBJ170A-TR.pdf
- Description:
- TVS DIODE 170VWM 275VC SMB
- Quantity:
- Payment:
- Shipping:
Inventory:4,625
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMBJ170A-TR from STMicroelectronics is a unidirectional transient voltage suppression (TVS) diode designed for primary-level surge protection on DC power rails and signal lines in industrial, telecom, and automotive electronics. It features a 170 V stand-off voltage (VRM), 275 V clamping voltage at 2.2 A (VCL), 600 W peak pulse power (10/1000 µs), and operates up to 150 °C junction temperature - deployed in SMPS input stages and PoE-powered equipment.
For engineers reviewing the SMBJ170A-TR datasheet, SMBJ170A-TR pinout, SMBJ170A-TR application, or SMBJ170A-TR equivalent, key selection criteria include clamping voltage margin relative to protected IC's absolute maximum rating, leakage current at elevated temperature (≤1 µA @ 85 °C), UL497B recognition for isolated loop circuits, and SMB package thermal performance under repeated surge stress.
Technical Context
This device uses planar silicon junction technology to achieve low leakage (0.2 µA @ 25 °C) and stable breakdown behavior across temperature. Its unidirectional configuration enables asymmetric clamping - conducting only during reverse overvoltage events while blocking forward conduction beyond its 1.2 V forward voltage at 10 A.
The SMBJ170A-TR delivers 350 W surge capability at 150 °C junction temperature and exhibits dynamic resistance of 12.7 Ω at 8/20 µs pulses - critical for limiting let-through energy into downstream MOSFETs or controllers during lightning-induced transients per IEC 61000-4-5.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Stand-off Voltage (VRM) | 170 V - Maximum continuous reverse operating voltage before clamping initiates; sets minimum system rail margin. |
| Breakdown Voltage (VBR min) | 189 V @ 1 mA - Confirmed minimum reverse breakdown threshold ensuring reliable turn-on above VRM. |
| Clamping Voltage (VCL) | 275 V @ 2.2 A (10/1000 µs) - Peak voltage seen by protected circuit during rated surge; defines worst-case stress level. |
| Peak Pulse Power (PPP) | 600 W (10/1000 µs) - Sustained surge energy handling at 25 °C; derates to 350 W at 150 °C junction temperature. |
| Leakage Current (IRM) | 0.2 µA @ 25 °C, 1 µA @ 85 °C - Low reverse leakage preserves efficiency in high-impedance sensing or battery-backed circuits. |
| Junction Temperature Range | −55 °C to +150 °C - Enables deployment in under-hood automotive modules and industrial motor drives without thermal derating penalties. |
| UL Recognition | UL497B (File E136224) - Certified for use as isolated loop circuit protector in telecom and building control systems. |
Pinout & Package
Manufactured in the industry-standard SMB (DO-214AA) surface-mount package with matte tin-plated leads compliant with J-STD-020 MSL Level 1 and IPC7531 footprint. The two-terminal device has no polarity marking on cathode side per standard SMB orientation; cathode is identified by band marking.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction path | Connected to lower-potential node (e.g., GND or return line); conducts during positive surges when used in reverse-biased configuration. |
| Cathode | Clamping reference terminal | Connected to protected line (e.g., 24 V rail); establishes reverse-bias condition enabling avalanche clamping above VRM. |
Key Features
| Feature | Design Value |
|---|---|
| Low clamping ratio (VCL/VBR ≈ 1.45) | Minimizes let-through overvoltage relative to breakdown threshold - critical for protecting 300 V-rated MOSFETs on 24–48 V rails. |
| High-temperature surge capability | 350 W (10/1000 µs) at Tj = 150 °C - maintains protection integrity in thermally constrained enclosures without forced cooling. |
| UL497B certified isolation rating | Recognized for isolated loop circuit protection - eliminates need for additional certification testing in building automation and PoE applications. |
| Low dynamic resistance (12.7 Ω) | Reduces voltage overshoot during fast-rising transients (e.g., IEC 61000-4-4 EFT bursts), improving immunity margin for microcontroller I/O. |
Applications
| Industrial Motor Drives | Telecom Power Feeds |
|---|---|
|
Use Scenario: Protection of gate drivers and bus voltage sense inputs against switching transients in 48 V BLDC inverters. IC Role / Device Role / Timing Role: Unidirectional TVS placed between high-side gate driver output and ground to clamp negative-going spikes induced by Miller capacitance. Use Value: Clamps to 275 V within <1 ns, preventing latch-up in 300 V-rated SiC gate drivers while maintaining <0.2 µA leakage at 85 °C ambient. |
Use Scenario: Surge suppression on −48 V DC feed lines in central office telecom racks exposed to lightning-induced surges. IC Role / Device Role / Timing Role: Primary protection element upstream of DC/DC converters, coordinated with secondary MOVs per IEC 61000-4-5 Level 4 (4 kV). Use Value: UL497B recognition validates compliance for isolated loop protection; 600 W rating handles repetitive 10/1000 µs surges without degradation. |
| Automotive Body Control Modules | Industrial PLC Analog Inputs |
|
Use Scenario: Input protection for LIN bus transceivers and power supply monitoring circuits in under-hood ECUs. IC Role / Device Role / Timing Role: Reverse-biased TVS on 12 V supply rail to suppress load dump transients per ISO 7637-2 Pulse 5a (up to 110 V, 100 ms). Use Value: 150 °C junction rating ensures operation in engine bay environments; 1 µA leakage at 85 °C prevents sensor bias drift in precision analog front-ends. |
Use Scenario: Overvoltage safeguard for 4–20 mA current loop receivers in factory-floor process controllers. IC Role / Device Role / Timing Role: Series-connected unidirectional TVS on loop return path to limit fault voltage during field wiring shorts or ESD events. Use Value: 275 V clamping ensures protected op-amp inputs remain below 30 V absolute max rating; SMB footprint allows dense layout near connector entry points. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ170CA-TR | Bidirectional variant with symmetric ±170 V stand-off and ±275 V clamping; higher capacitance (~100 pF @ 0 V). | Required where AC-coupled signals or bidirectional data lines (e.g., RS-485) need symmetrical surge protection. | Select only if bidirectional clamping is mandated; otherwise SMBJ170A-TR offers lower leakage and better DC rail efficiency. |
| SMBJ150A-TR | Lower stand-off (150 V) and clamping (246 V); same SMB package and thermal specs. | Suitable for 120–130 V nominal DC systems where tighter clamping margin is needed relative to downstream 200 V-rated components. | Choose when protected circuit's absolute max rating is ≤250 V and design requires lower let-through voltage than SMBJ170A-TR provides. |
Compared with SMBJ170CA-TR, the unidirectional SMBJ170A-TR reduces leakage by 3× in DC-biased applications and avoids unnecessary capacitance on high-speed lines; versus SMBJ150A-TR, it provides 20 V higher stand-off margin for 170 V nominal rails, reducing false-trigger risk during brownout conditions.
Availability
SMBJ170A-TR is available at Aetrix Electronics and suitable for industrial motor drives, telecom power feeds, and automotive body control modules requiring stable component supply with full traceability and long-term lifecycle support.
Supply support for SMBJ170A-TR 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in power management, analog, MEMS, and microcontroller technologies for industrial, automotive, and consumer markets.
The SMBJ series belongs to ST's high-reliability TVS portfolio engineered specifically for robust surge immunity in harsh-environment power electronics - emphasizing low leakage, high-temperature stability, and regulatory compliance for mission-critical infrastructure.
FAQ
What is the maximum surge current SMBJ170A-TR can handle at 8/20 µs?
The SMBJ170A-TR sustains 353 A peak pulse current under an 8/20 µs waveform, corresponding to its 4 kW surge rating. This value is confirmed in Table 2 of DS1283 Rev 14 and validated per IEC 61000-4-5 test conditions with 25 °C initial junction temperature.
Does SMBJ170A-TR meet automotive AEC-Q200 requirements?
No - SMBJ170A-TR is not AEC-Q200 qualified. It is rated for industrial and telecom applications with operating junction temperature up to 150 °C and UL497B recognition, but lacks the extended temperature cycling, humidity, and vibration testing required for automotive qualification.
How does the dynamic resistance affect clamping performance?
With a measured dynamic resistance (RD) of 12.7 Ω at 8/20 µs, the SMBJ170A-TR adds predictable voltage rise (ΔV = RD × ΔI) during surge events - enabling accurate let-through voltage estimation using VCL(max) = VCL − RD × (IPP − IPPappli) as defined in DS1283.
Can SMBJ170A-TR be used in parallel for higher power handling?
Parallel operation is not recommended due to mismatch in VBR and thermal coupling effects. ST specifies single-device ratings only; for >600 W needs, select higher-rated devices like 1.5KE170A or consider staged protection with upstream MOVs and downstream TVS arrays.
SMBJ170A-TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- DO-214AA, SMB
- Series:
- SMBJ, TRANSIL™
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 170V
- Voltage - Breakdown (Min):
- 189V
- Voltage - Clamping (Max) @ Ipp:
- 275V
- Current - Peak Pulse (10/1000µs):
- 2.2A
- Power - Peak Pulse:
- 600W
- 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:
- SMB
SMBJ170A-TR FAQ
1.How can I place an order for SMBJ170A-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for SMBJ170A-TR 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 SMBJ170A-TR reliable?
The price and inventory of SMBJ170A-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMBJ170A-TR is usually 5 days.
3.What payment methods are accepted for SMBJ170A-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMBJ170A-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMBJ170A-TR?
SMBJ170A-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMBJ170A-TR 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 SMBJ170A-TR?
For technical support, including SMBJ170A-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMBJ170A-TR requirements.
6.How does Aetrix verify that SMBJ170A-TR is sourced from the original manufacturer or authorized distributors?
All SMBJ170A-TR 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 SMBJ170A-TR meets industry standards.
7.What is the process for return or replacement of SMBJ170A-TR?
All SMBJ170A-TR units undergo pre-shipment inspection (PSI). If there is an issue with SMBJ170A-TR, 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 SMBJ170A-TR part is unused and in its original packaging.
Return procedure for SMBJ170A-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMBJ170A-TR 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…
