My Inquiry
My Account
STMicroelectronics SMAJ22CA-TR
- Part No.:
- SMAJ22CA-TR
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ22CA-TR.pdf
- Description:
- TVS DIODE 22VWM 48.3VC SMA
- Quantity:
- Payment:
- Shipping:
Inventory:6,835
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMAJ22CA-TR from STMicroelectronics is a bidirectional transient voltage suppression (TVS) diode in SMA package, designed for IEC 61000-4-2 ESD and IEC 61000-4-4 surge protection. It features a 22 V standoff voltage (VRM), 35.5 V clamping voltage at 10.3 A (8/20 µs), 400 W peak pulse power (10/1000 µs), and operates up to 150 °C junction temperature - deployed in industrial power supplies and automotive body control modules.
For engineers reviewing the SMAJ22CA-TR datasheet, SMAJ22CA-TR pinout, SMAJ22CA-TR application, or SMAJ22CA-TR equivalent, key selection criteria include bidirectional clamping behavior, low leakage (<1 µA at 85 °C), JEDEC DO-214AC (SMA) footprint compliance, and IEC 61000-4-2 level 4 (±30 kV contact/air) validation.
Technical Context
This TVS diode uses planar silicon junction technology to achieve stable breakdown characteristics and low dynamic resistance (0.637 Ω at 25 °C). Its bidirectional configuration enables symmetrical clamping for AC-coupled signal lines and ungrounded interfaces without polarity dependency.
The device meets IEC 61000-4-4 level 4 (4 kV) surge immunity and exceeds IEC 61000-4-2 level 4 for both contact and air discharge (30 kV), with thermal design validated for FR4 PCBs using IPC-7531-compliant footprints and 70 µm copper thickness.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRM) | 22 V - maximum continuous reverse working voltage before clamping initiates |
| Breakdown Voltage (VBR) | 24.4–25.8 V at 1 mA - ensures reliable triggering margin above VRM |
| Clamping Voltage (VCL) | 35.5 V at 10.3 A (8/20 µs) - limits downstream voltage stress during surge events |
| Peak Pulse Power (PPP) | 400 W (10/1000 µs) - supports repetitive surge handling in industrial power rails |
| Leakage Current (IRM) | 0.2 µA at 25 °C, 1 µA at 85 °C - preserves signal integrity in high-impedance sensor interfaces |
| Junction Temperature Range | −55 to +150 °C - enables deployment in under-hood automotive and industrial motor drives |
| Package | DO-214AC (SMA) - surface-mount outline compliant with IPC-7531 and JEDEC MS-013 |
Pinout & Package
DO-214AC (SMA) package: molded plastic case with two coplanar cathode-marked terminals; dimensions per JEDEC outline (E = 4.80–5.35 mm, D = 2.25–2.90 mm, L = 0.75–1.50 mm); matte tin-plated leads, MSL Level 1, RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (marked band) | Surge current sink node | Primary conduction path during positive transients in bidirectional operation |
| Anode | Surge current sink node | Primary conduction path during negative transients; symmetric clamping with cathode |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional clamping | Enables single-device protection of AC signals and floating buses without polarity constraints |
| Low dynamic resistance | 0.637 Ω at 25 °C - minimizes voltage overshoot during fast 8/20 µs surges |
| High-temperature reliability | Rated for 150 °C Tj - maintains clamping stability in thermally stressed environments |
| IEC 61000-4-2 level 4 compliance | Withstands ±30 kV contact/air discharge - eliminates need for external ESD staging in end equipment |
| Planar junction construction | Delivers consistent VBR tolerance and low leakage across production lots and temperature range |
Applications
| Industrial PLC I/O Protection | Automotive Body Control Module |
|---|---|
Use Scenario: Protecting 24 V DC digital input channels against load dump and inductive switching transients. IC Role / Device Role / Timing Role: Bidirectional TVS clamp placed between field wiring and microcontroller GPIO, absorbing energy before it reaches protection circuitry. Use Value: Limits transient voltage to ≤35.5 V during 10.3 A surges, preventing latch-up or permanent damage to 3.3 V/5 V logic interfaces. | Use Scenario: Safeguarding LIN bus transceivers and door module sensors from battery line disturbances. IC Role / Device Role / Timing Role: Standoff-rated TVS on LIN signal line (VRWM = 22 V) providing symmetrical clamping for bidirectional communication. Use Value: Maintains signal integrity under ±30 kV ESD events while adding <1 µA leakage at 85 °C - critical for low-power wake-up circuits. |
| AC-DC Power Supply Input Stage | Smart Meter Communication Interface |
Use Scenario: Secondary-side surge suppression on 24 V auxiliary rail feeding isolated MCU and display drivers. IC Role / Device Role / Timing Role: Fast-response TVS placed after bulk filter capacitor, shunting 400 W (10/1000 µs) surges away from downstream regulators. Use Value: Clamps to 35.5 V within nanoseconds, limiting overvoltage stress on 36 V-rated DC-DC converters and enabling compact board layout. | Use Scenario: Protecting RS-485 transceivers in utility meters exposed to lightning-induced surges on long outdoor runs. IC Role / Device Role / Timing Role: Bidirectional TVS on differential pair, rated for 4 kV IEC 61000-4-4 level 4, placed before transceiver inputs. Use Value: Survives repeated 8/20 µs surges up to 10.3 A without parameter drift, ensuring 10+ year field reliability in harsh grid environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ22CA-TR | Higher PPP (600 W, 10/1000 µs), SMB package (larger footprint, lower thermal resistance) | Better suited for higher-energy surges where PCB space allows larger package | Select when surge energy exceeds 400 W but layout permits SMB footprint |
| P6SMB22CA | Same PPP (600 W), same VRWM, but legacy SMB package with higher leakage (5 µA @ 85 °C) | Less suitable for low-power wake-up circuits due to elevated leakage | Prefer only if legacy BOM compatibility required and leakage sensitivity is low |
Compared with SMAJ22CA-TR, SMBJ22CA-TR offers 50% higher surge energy handling in a physically larger package, while P6SMB22CA trades off leakage performance for broad industry familiarity - making SMAJ22CA-TR optimal for space-constrained, low-leakage, and thermally demanding designs.
Availability
SMAJ22CA-TR is available at Aetrix Electronics and suitable for industrial PLC I/O protection, automotive body control modules, and AC-DC auxiliary power supply input stages requiring stable component supply and full IEC 61000-4-2/4-4 compliance.
Supply support for SMAJ22CA-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 microcontrollers for industrial, automotive, and consumer markets.
The SMAJ series belongs to ST's transient protection portfolio, engineered specifically for robust, low-leakage, surface-mount TVS solutions targeting IEC-compliant surge and ESD hardening in space-constrained, high-reliability systems.
FAQ
What is the clamping voltage of SMAJ22CA-TR under an 8/20 µs surge?
The clamping voltage (VCL) is 35.5 V at 10.3 A for an 8/20 µs waveform, measured at Tamb = 25 °C. This value increases with junction temperature per αT = 10⁻⁴ /°C, reaching ~37.2 V at 125 °C junction temperature - critical for margining against downstream IC absolute maximum ratings.
Is SMAJ22CA-TR unidirectional or bidirectional?
SMAJ22CA-TR is a bidirectional TVS diode, indicated by the "CA" suffix. It provides symmetrical clamping for both polarities, making it suitable for AC-coupled lines, differential buses (e.g., RS-485, LIN), and floating signal paths where polarity cannot be assumed.
Does SMAJ22CA-TR meet automotive qualification standards?
While not AEC-Q200 qualified, SMAJ22CA-TR meets IEC 61000-4-2 (±30 kV ESD) and IEC 61000-4-4 (4 kV surge) - widely adopted in automotive body electronics. Its 150 °C Tj rating and low leakage support under-hood ambient conditions when properly heatsinked on FR4 with recommended copper area.
What is the thermal resistance of SMAJ22CA-TR on a standard FR4 PCB?
On a standard FR4 board with 70 µm copper and IPC-7531 footprint, Rth(j-a) is approximately 120 °C/W for a single pulse. With 2 cm² copper area per lead, thermal resistance drops to ~3.5 °C/W - enabling sustained operation near Tj = 150 °C under intermittent surge duty cycles.
SMAJ22CA-TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- DO-214AC, SMA
- Series:
- SMAJ, TRANSIL™
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 22V
- Voltage - Breakdown (Min):
- 24.4V
- Voltage - Clamping (Max) @ Ipp:
- 48.3V
- Current - Peak Pulse (10/1000µs):
- 48A (8/20µs)
- Power - Peak Pulse:
- 400W
- 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:
- DO-214AC (SMA)
SMAJ22CA-TR FAQ
1.How can I place an order for SMAJ22CA-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ22CA-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 SMAJ22CA-TR reliable?
The price and inventory of SMAJ22CA-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ22CA-TR is usually 5 days.
3.What payment methods are accepted for SMAJ22CA-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ22CA-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ22CA-TR?
SMAJ22CA-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ22CA-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 SMAJ22CA-TR?
For technical support, including SMAJ22CA-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ22CA-TR requirements.
6.How does Aetrix verify that SMAJ22CA-TR is sourced from the original manufacturer or authorized distributors?
All SMAJ22CA-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 SMAJ22CA-TR meets industry standards.
7.What is the process for return or replacement of SMAJ22CA-TR?
All SMAJ22CA-TR units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ22CA-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 SMAJ22CA-TR part is unused and in its original packaging.
Return procedure for SMAJ22CA-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ22CA-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…
