My Inquiry
My Account
Semtech Corporation SCHJ45K
- Part No.:
- SCHJ45K
- Manufacturer:
- Semtech Corporation
- Category:
- Single Diodes
- Package:
- Axial
- Datasheet:
-
SCHJ45K.pdf
- Description:
- DIODE GEN PURP 45KV 50MA AXIAL
- Quantity:
- Payment:
- Shipping:
Inventory:7,481
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SCHJ45K from Semtech is a Transient Diverting Suppressor (TDS) designed for high-energy EOS protection of 22V-rated power or I/O lines. It delivers ±30kV IEC 61000-4-2 ESD immunity, 40A peak pulse current (8/20μs), and stable 27.5–28V clamping across temperature and current range - enabling robust USB Type-C PD and industrial load switch input protection.
For engineers reviewing the SCHJ45K datasheet, pinout, applications, or equivalent options, this page provides verified electrical parameters, DFN-6 package layout guidance, clamping stability data, and direct alternatives for 22V bus protection in high-reliability embedded systems.
Technical Context
The SCHJ45K uses a surge-rated FET as its primary protection element, activated by a precision trigger circuit upon EOS detection. Unlike conventional TVS diodes, its clamping voltage remains nearly constant due to decreasing RDS(on) under surge - not fixed dynamic resistance.
It operates over −40°C to +125°C with <20mΩ dynamic resistance (8/20μs), 175pF junction capacitance at 22V/1MHz, and <600nA reverse leakage. The device requires all three IN pins (4–6) and all three GND pins (1–3) connected for full 40A rating and minimal parasitic inductance.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Working Voltage | 22V - defines maximum continuous DC bus voltage before leakage rises significantly. |
| Clamping Voltage | 27.5–28V at 40A (8/20μs + 1.2/50μs combo wave, RS=2Ω) - ensures protected ICs see ≤28V during worst-case surges. |
| Peak Pulse Current | 40A (8/20μs) - meets IEC 61000-4-5 Level 4 industrial surge immunity requirements. |
| ESD Withstand | ±30kV contact & air (IEC 61000-4-2) - exceeds USB PD and industrial ESD immunity mandates. |
| Junction Capacitance | 175pF at 22V/1MHz - low enough for 22V power rail protection without signal integrity impact. |
| Dynamic Resistance | 20mΩ (8/20μs, 1–40A range) - enables flat clamping curve and minimizes VC rise with increasing IPP. |
| Package | DFN 1.6×1.6×0.55mm, 6-lead - enables ultra-compact placement near USB-C connectors or load switch inputs. |
Pinout & Package
Package: DFN 1.6 mm × 1.6 mm × 0.55 mm, 6-lead, Pb-free, RoHS/WEEE compliant, UL 94V-0 molding compound.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 2, 3 | GND | Common ground return path for surge current; all three must be connected to minimize inductance and achieve full 40A rating. |
| 4, 5, 6 | IN | Protected line input (e.g., VBus, load switch VIN); parallel connection ensures uniform current sharing and thermal distribution. |
Key Features
| Feature | Design Value |
|---|---|
| Constant clamping voltage | 27.5–28V across 24–40A and −40°C to +125°C - eliminates derating uncertainty vs. temperature-dependent TVS diodes. |
| FET-based shunt architecture | Surge-rated MOSFET + precision trigger circuit - achieves <20mΩ dynamic resistance and avoids junction heating limitations of PN-junction TVS. |
| Low leakage & high EFT immunity | <600nA @22V and ±4kV EFT (IEC 61000-4-4) - ensures no system reset or false triggering in noisy industrial environments. |
| Space-optimized DFN layout | 1.6×1.6mm footprint with 3-pin IN/3-pin GND symmetry - supports symmetric PCB routing and reduces trace inductance vs. discrete TVS arrays. |
Applications
| USB Type-C Power Delivery Protection | Industrial Load Switch Input Protection |
|---|---|
Use Scenario: Protecting 20V–22V USB PD bus against lightning-induced surges and connector ESD events in portable notebooks and docking stations. IC Role / Device Role / Timing Role: Primary EOS shunt suppressor placed between VBus and GND, upstream of PD controller and load switch. Use Value: Maintains 28V clamping at 40A and 125°C - prevents PD controller latch-up or gate oxide damage where conventional TVS would exceed 35V. |
Use Scenario: Safeguarding input of industrial-grade load switches (e.g., HS2950P) in remote meters and robotics against 1kV/42Ω surges per IEC 61000-4-5. IC Role / Device Role / Timing Role: Front-end transient clamp limiting voltage seen by internal FET drain-source junction. Use Value: Clamps below 28V regardless of ambient temperature - avoids overvoltage stress on load switch's absolute maximum VDS rating (typically 30–36V). |
| IoT Edge Node Power Bus Protection | Storage Device 22V Rail Protection |
Use Scenario: Securing 22V auxiliary power rails in battery-backed IoT gateways exposed to ESD during field servicing or lightning-coupled transients. IC Role / Device Role / Timing Role: Single-device solution replacing multi-TVS or MOV+TVS hybrid designs for compact edge hardware. Use Value: 175pF capacitance and 22V working voltage enable clean DC rail filtering without compromising surge margin - unlike higher-capacitance alternatives. |
Use Scenario: Protecting 22V supply inputs of NVMe SSD modules and enterprise storage controllers against hot-plug transients and backplane coupling. IC Role / Device Role / Timing Role: High-energy transient diverter placed at board edge, adjacent to power connector. Use Value: 1120W peak pulse power rating sustains repeated 40A surges without degradation - critical for mission-critical storage uptime. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TDS2211P | Same die, identical electrical specs and package - SCHJ45K is Semtech's alternate marking for TDS2211P per official ordering documentation. | Identical use cases: USB PD, load switch input, 22V rail protection. | Select SCHJ45K when sourcing from Aetrix Electronics' inventory; identical performance and footprint to TDS2211P. |
| uClamp2411ZA | 24V working voltage, lower 25A IPP rating, ±30kV ESD, but uses standard TVS architecture - clamping rises with current/temperature. | Targeted at CC/SBU lines in USB-C, not main VBus; unsuitable for 40A surge handling. | Use only for auxiliary signal lines; not a functional replacement for SCHJ45K's 22V/40A power rail role. |
Compared with TDS2211P, SCHJ45K is an identical device with alternate marking - no design change required. Compared with uClamp2411ZA, SCHJ45K offers 60% higher peak current capability, flat clamping, and proven suitability for 22V power bus protection rather than signal-line duty.
Availability
SCHJ45K is available at Aetrix Electronics and suitable for USB Type-C PD systems, industrial load switch inputs, and 22V IoT power bus designs requiring stable component supply, long-term lifecycle support, and RoHS-compliant surge protection.
Supply support for SCHJ45K 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
Semtech Corporation is a U.S.-based fabless semiconductor company specializing in analog and mixed-signal ICs for precision sensing, protection, and connectivity.
The Transient Diverting Suppressor (TDS) product line was engineered to replace conventional TVS diodes in high-reliability 22V–36V power rail protection, delivering flat clamping and temperature-stable surge handling for USB PD, industrial, and storage applications.
FAQ
What is the exact relationship between SCHJ45K and TDS2211P?
SCHJ45K is Semtech's alternate part number and marking code for the identical TDS2211P device. Both share the same die, DFN-6 package, electrical specifications (22V working voltage, 40A IPP, 27.5–28V clamping), and qualification data per Rev 2.5 datasheet. No design or layout changes are needed when substituting SCHJ45K for TDS2211P.
Does SCHJ45K require external components for basic operation?
No. SCHJ45K is a fully self-contained transient suppressor requiring no external resistors, capacitors, or bias networks. Its integrated trigger circuit and shunt FET activate automatically during EOS events. However, PCB layout must connect all three IN pins (4–6) and all three GND pins (1–3) with low-inductance traces to achieve rated 40A performance.
Can SCHJ45K be used to protect a 24V industrial power rail?
No. SCHJ45K has a 22V reverse stand-off voltage (VRWM) and 25V typical breakdown voltage (VBR). Operating continuously above 22V risks excessive leakage current and premature triggering. For 24V rails, select a device with ≥26V VRWM, such as Semtech's TDS2411P - SCHJ45K is strictly rated for ≤22V nominal systems.
How does SCHJ45K's clamping behavior differ from standard TVS diodes?
SCHJ45K uses a triggered FET shunt, yielding <20mΩ dynamic resistance and near-constant 27.5–28V clamping from 1A to 40A. Standard TVS diodes follow VC = VBR + IPP × RDYN, causing clamping to rise linearly with current and temperature - e.g., a 22V TVS may clamp at >38V at 40A/125°C, whereas SCHJ45K stays at ~28V.
Is SCHJ45K suitable for protecting high-speed data lines like USB SuperSpeed?
No. SCHJ45K's 175pF junction capacitance is optimized for power/IO line protection, not signal integrity. For USB SS TX/RX, DP/DM, or PCIe lanes, use low-capacitance TVS devices like RClamp3371ZC (<0.25pF). SCHJ45K is intended exclusively for VBus, CC, SBU, or load switch VIN - not differential data pairs.
SCHJ45K Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Semtech Corporation
- Series:
- -
- Package/Case:
- Axial
- Packaging:
- Bulk
- Product Status:
- Discontinued at Digi-Key
- Technology:
- Standard
- Voltage - DC Reverse (Vr) (Max):
- 45000 V
- Current - Average Rectified (Io):
- 50mA
- Voltage - Forward (Vf) (Max) @ If:
- 60 V @ 100 mA
- Speed:
- Small Signal =< 200mA (Io), Any Speed
- Reverse Recovery Time (trr):
- 2.5 µs
- Current - Reverse Leakage @ Vr:
- 1 µA @ 45000 V
- Capacitance @ Vr, F:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- -
- Operating Temperature - Junction:
- -55°C ~ 150°C
SCHJ45K FAQ
1.How can I place an order for SCHJ45K through Aetrix?
Please submit a Request for Quotation (RFQ) for SCHJ45K 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 SCHJ45K reliable?
The price and inventory of SCHJ45K are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SCHJ45K is usually 5 days.
3.What payment methods are accepted for SCHJ45K?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SCHJ45K transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SCHJ45K?
SCHJ45K orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SCHJ45K 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 SCHJ45K?
For technical support, including SCHJ45K datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SCHJ45K requirements.
6.How does Aetrix verify that SCHJ45K is sourced from the original manufacturer or authorized distributors?
All SCHJ45K 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 SCHJ45K meets industry standards.
7.What is the process for return or replacement of SCHJ45K?
All SCHJ45K units undergo pre-shipment inspection (PSI). If there is an issue with SCHJ45K, 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 SCHJ45K part is unused and in its original packaging.
Return procedure for SCHJ45K:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SCHJ45K Tags
-
1N4448X-TP
Micro Commercial Co
-
1N4148WX-TP
Micro Commercial Co
-
1N4148TR
onsemi
-
MMSD4148T1G
onsemi
-
MMBD914LT3G
onsemi
-
BAS16HT1G
onsemi
-
1N914BWT
onsemi
-
BAS21LT1G
onsemi
-
LL4148
onsemi
-
BAS16LT1G
onsemi
-
MMSD914T1G
onsemi
-
BAV21W-7-F
Diodes Incorporated
Tech Hub
Comparator circuit design covering voltage thresholds, input limits, open-collector outputs, LM393 wiring, op-amp differences, hysteresis, timing, window detection and practical fault diagnosis.
Schmitt triggers use separate rising and falling thresholds to stabilize slow or noisy signals. This guide covers hysteresis, 74HC14 and 74HCT14 selection, comparator calculations, RC oscillators and p…
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 …
