My Inquiry
My Account
onsemi SM05T1
- Part No.:
- SM05T1
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
SM05T1.pdf
- Description:
- TVS DIODE 5VWM 9.8VC SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:7,186
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SM05T1 from onsemi is a dual common-anode transient voltage suppressor (TVS) diode array in SOT-23 package, designed for ESD and surge protection of two independent signal lines. It features 5.0 V working peak reverse voltage (VRWM), 9.8 V clamping voltage (VC) at 17 A peak pulse current, and 300 W peak pulse power (8 × 20 µs). It is used in USB, keyboard, and I/O port protection where board space is constrained.
For engineers reviewing the SM05T1 datasheet, pinout, applications, or equivalent options, key selection criteria include bidirectional/unidirectional configuration flexibility, low clamping voltage under 17 A stress, UL 94 V-0 flammability rating, and compatibility with automated SMT assembly on FR-5 or alumina substrates.
Technical Context
The SM05T1 integrates two monolithic silicon zener junctions sharing a common anode (Pin 3), enabling dual-line unidirectional protection or single-line bidirectional operation via external routing. Its breakdown voltage (VBR) is 6.2–7.3 V at 1 mA test current, with typical capacitance of 225 pF at 0 V bias - optimized for low-speed data lines like RS-232 or parallel I/O.
It meets IEC 61000-4-2 (±15 kV air, ±8 kV contact), IEC 61000-4-4 (40 A EFT), and IEC 61000-4-5 (12 A lightning surge) standards. Thermal resistance is 556 °C/W on FR-5 board, limiting steady-state dissipation to 225 mW at 25 °C ambient.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 5.0 V - Maximum continuous reverse operating voltage before conduction begins; sets minimum system supply margin for protected lines. |
| VBR (min/max) | 6.2 V / 7.3 V at 1 mA - Ensures predictable turn-on across process variation; defines lower bound of clamping onset. |
| VC @ IPP = 17 A | 9.8 V - Clamped voltage during 8 × 20 µs surge; must stay below IC absolute maximum ratings of downstream devices. |
| IPP (max) | 17 A - Peak pulse current capability per line; determines survivability against IEC 61000-4-5 Level 2 surges. |
| Capacitance @ 0 V | 225 pF - Limits high-frequency signal integrity degradation; suitable for ≤1 MHz digital interfaces. |
| Leakage @ VRWM | <1 µA - Minimizes standby power loss and avoids false triggering in high-impedance sensing circuits. |
| Package | SOT-23 (Case 318, Style 12) - Enables 0.95 mm × 2.0 mm footprint; supports high-density PCB layouts and standard reflow profiles. |
Pinout & Package
SOT-23 package (Case 318, Style 12), void-free thermosetting plastic case with corrosion-resistant, solderable finish. Maximum soldering temperature: 260 °C for 10 seconds.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 | Cathode (Line 1) | Connects to first protected signal line; reverse-biased during normal operation; conducts during overvoltage events. |
| Pin 2 | Cathode (Line 2) | Connects to second protected signal line; electrically isolated from Pin 1 except through shared anode (Pin 3). |
| Pin 3 | Common Anode | Reference node tied to system ground or common return; enables dual-line protection with single-package footprint. |
Key Features
| Feature | Design Value |
|---|---|
| Dual-line protection in one SOT-23 | Reduces PCB area by ~50% vs. two discrete SOT-23 TVS diodes; eliminates inter-trace coupling risk in split layouts. |
| Configurable unidirectional/bidirectional mode | Pin 1–3 and Pin 2–3 form independent unidirectional clamps; Pins 1–2 with external series resistor enable bidirectional behavior. |
| UL 94 V-0 flammability rating | Confirms self-extinguishing polymer housing under flame exposure - required for end-equipment safety certifications. |
| Low clamping ratio (VC/VBR ≈ 1.4) | Minimizes voltage overshoot during transients; improves margin for 5 V logic ICs with 6 V absolute max ratings. |
| ESD robustness (±15 kV air, ±8 kV contact) | Meets IEC 61000-4-2 Level 4 - sufficient for handheld peripherals, industrial HMI, and medical device front panels. |
Applications
| USB 2.0 Data Line Protection | Keyboard/Mouse Interface Protection |
|---|---|
Use Scenario: Protecting D+ and D− lines of a USB 2.0 host port against ESD events during cable insertion or handling. IC Role / Device Role / Timing Role: Transient voltage suppressor providing low-capacitance, fast-response clamping to limit voltage excursion below 10 V. Use Value: Prevents latch-up or gate oxide damage in USB transceivers while maintaining signal integrity up to 480 Mbps due to 225 pF capacitance. |
Use Scenario: Shielding PS/2 or USB keyboard scan matrix lines from user-induced ESD in office equipment. IC Role / Device Role / Timing Role: Dual-line TVS diode array absorbing ±8 kV contact discharges without disrupting key matrix scanning timing. Use Value: Eliminates need for separate diodes per line; ensures reliable key detection after repeated ESD strikes with no parameter drift. |
| Industrial I/O Terminal Protection | Microprocessor Parallel Bus Protection |
Use Scenario: Guarding RS-485 or GPIO lines on PLC modules exposed to field wiring surges and induced transients. IC Role / Device Role / Timing Role: Surge suppression element rated for 12 A IEC 61000-4-5 (line-earth) surges on 24 V industrial buses. Use Value: Withstands repetitive 300 W pulses without degradation; maintains leakage <1 µA to avoid false logic states in high-impedance inputs. |
Use Scenario: Safeguarding address/data/control bus lines (e.g., A0–A15, D0–D7, RD#, WR#) on 8-bit microcontrollers in embedded controllers. IC Role / Device Role / Timing Role: Common-anode dual TVS array clamping all bus lines referenced to ground during ESD events on any pin. Use Value: Prevents bus contention or reset glitches caused by transient-induced voltage spikes; compatible with 5 V TTL logic thresholds. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| PESD5V0S1BA,115 (Nexperia) | Single-line SOT-23 TVS; 5.0 V VRWM; 12.5 V VC @ 4 A; 120 pF capacitance. | Lower capacitance but only protects one line; requires two units for dual-line coverage. | Prefer when signal bandwidth >10 MHz or layout allows separate placement per line. |
| SMAJ5.0A (onsemi) | Single-line SMA package; 5.0 V VRWM; 9.2 V VC @ 15.2 A; 500 pF capacitance; higher power (400 W). | Larger footprint (4.5 × 2.7 mm); higher capacitance limits use to sub-MHz signals. | Choose for higher surge energy handling where board space permits larger package. |
Compared with PESD5V0S1BA,115 and SMAJ5.0A, the SM05T1 uniquely delivers dual-line protection in SOT-23 with balanced clamping (9.8 V) and moderate capacitance (225 pF), making it optimal for space-constrained 5 V digital interfaces requiring coordinated line protection without added layout complexity.
Availability
SM05T1 is available at Aetrix Electronics and suitable for USB interface protection, industrial I/O terminal safeguarding, and microcontroller bus line hardening requiring stable component supply and long-term production continuity.
Supply support for SM05T1 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 specializing in energy-efficient power management, analog, sensor, and logic solutions for automotive, industrial, cloud, and consumer markets.
The SM05T1 belongs to onsemi's transient voltage suppressor diode array product line, engineered specifically for compact, high-reliability ESD and surge protection in space-limited digital interfaces and peripheral ports.
FAQ
What is the maximum clamping voltage of the SM05T1 under IEC 61000-4-2 ESD stress?
The SM05T1 clamps to 9.8 V at 17 A peak pulse current (8 × 20 µs waveform), which corresponds to its specified IEC 61000-4-2 contact discharge level of ±8 kV. This value is measured per line (Pin 1–3 or Pin 2–3) and remains consistent across temperature and lifetime when operated within datasheet limits. The SM05T1 maintains this clamping performance without degradation after repeated ESD events.
Can the SM05T1 be used for bidirectional signal line protection?
Yes - the SM05T1 supports bidirectional protection by connecting both cathodes (Pins 1 and 2) to the same signal line and the common anode (Pin 3) to ground, with a series current-limiting resistor. This configuration leverages the symmetric zener characteristics of both junctions. However, the SM05T1 is primarily characterized and tested in unidirectional mode (Pin 1–3 and Pin 2–3), and bidirectional use requires validation of clamping symmetry in the target circuit.
What is the thermal resistance of the SM05T1 on a standard FR-5 PCB?
The SM05T1 has a junction-to-ambient thermal resistance (RθJA) of 556 °C/W when mounted on a 1.0 × 0.75 × 0.62 inch FR-5 board using the recommended SOT-23 footprint. This results in a maximum steady-state power dissipation of 225 mW at 25 °C ambient. Derating is linear at 1.8 mW/°C above 25 °C, meaning usable power drops to 135 mW at 75 °C ambient.
Does the SM05T1 meet UL 94 flammability requirements?
Yes - the SM05T1 package carries a UL 94 V-0 flammability rating, verified per Underwriters Laboratories testing protocol. This confirms the thermosetting plastic case will self-extinguish within 10 seconds after flame removal and not drip flaming particles. The rating applies to the completed device and supports compliance for end equipment seeking UL/CSA certification.
How is the SM05T1 marked on the package?
The SM05T1 is laser-marked with "5M" on the top surface of the SOT-23 package, where "5" denotes the 5.0 V VRWM variant and "M" is the date code. This marking aligns with onsemi's standard SOT-23 labeling convention and matches the ordering information in the SM05T1/D datasheet. No additional logos or secondary identifiers appear on the device body.
SM05T1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 2
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 5V
- Voltage - Breakdown (Min):
- 6.2V
- Voltage - Clamping (Max) @ Ipp:
- 9.8V
- Current - Peak Pulse (10/1000µs):
- 17A (8/20µs)
- Power - Peak Pulse:
- 300W
- 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:
- SOT-23-3 (TO-236)
SM05T1 FAQ
1.How can I place an order for SM05T1 through Aetrix?
Please submit a Request for Quotation (RFQ) for SM05T1 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 SM05T1 reliable?
The price and inventory of SM05T1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SM05T1 is usually 5 days.
3.What payment methods are accepted for SM05T1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SM05T1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SM05T1?
SM05T1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SM05T1 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 SM05T1?
For technical support, including SM05T1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SM05T1 requirements.
6.How does Aetrix verify that SM05T1 is sourced from the original manufacturer or authorized distributors?
All SM05T1 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 SM05T1 meets industry standards.
7.What is the process for return or replacement of SM05T1?
All SM05T1 units undergo pre-shipment inspection (PSI). If there is an issue with SM05T1, 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 SM05T1 part is unused and in its original packaging.
Return procedure for SM05T1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SM05T1 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
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
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…
