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STMicroelectronics LDP01-42AY
- Part No.:
- LDP01-42AY
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- TO-263-3, D2PAK (2 Leads + Tab), TO-263AB
- Datasheet:
-
LDP01-42AY.pdf
- Description:
- TVS DIODE 36VWM 57VC D2PAK
- Quantity:
- Payment:
- Shipping:
Inventory:1,447
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Product details
Overview
LDP01-42AY from STMicroelectronics is an AEC-Q101-qualified automotive Transil™ TVS diode designed for load-dump protection in 12 V and 24 V vehicle electrical systems. It features a 42 V nominal breakdown voltage (VBR = 40–44.2 V at IR = 1 mA), clamps to 71 V at 1000 A (8/20 µs), delivers 1000 W peak pulse power at Tj = 25 °C, and operates up to 175 °C junction temperature - deployed across engine control units, body control modules, and infotainment power rails.
For engineers reviewing the LDP01-42AY datasheet, LDP01-42AY pinout, LDP01-42AY application, or LDP01-42AY equivalent, key selection criteria include ISO 7637-2 Pulse 5a/b and ISO 16750-2 Test A/B compliance, low leakage (<1 µA at 25 °C), D²PAK thermal performance (Rth(j-c) = 0.24 °C/W), and verified clamping behavior under 1000 A surge conditions.
Technical Context
The LDP01-42AY employs planar silicon avalanche technology optimized for high-reliability automotive transients, with bidirectional clamping capability and symmetrical voltage-temperature coefficient (αT = 10 × 10−4/°C). Its structure supports dual-anode configuration, enabling robust handling of both positive and negative load-dump events without polarity constraints.
It meets stringent automotive surge standards: ISO 7637-2 Pulse 5a (−150 V) and 5b (+112 V), ISO 16750-2 Tests A (up to +75 V) and B (up to +80 V), and IEC 61000-4-2/ISO 10605 ESD (±30 kV). Thermal derating is defined by junction-to-case resistance (0.24 °C/W) and maximum Tj = 175 °C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Breakdown Voltage VBR | 40–44.2 V at IR = 1 mA - defines minimum clamping threshold before avalanche conduction begins |
| Clamping Voltage VCL | 71 V at IPP = 1000 A (8/20 µs) - maximum voltage seen by protected circuit during worst-case surge |
| Peak Pulse Power | 1000 W at Tj = 25 °C - sustains 1000 A surge for 8/20 µs without failure |
| Leakage Current IR | <1 µA at VRM = 36 V and 25 °C - ensures minimal standby power loss in always-on automotive modules |
| Junction Temperature Range | −55 to +175 °C - enables operation in under-hood environments including near engines and powertrain ECUs |
| Dynamic Impedance RD | 27 mΩ (8/20 µs) - determines voltage rise slope (VCL = RD × IPP + VBR(max)) during transient |
Pinout & Package
Supplied in JEDEC-registered D²PAK (TO-263AB) package with exposed copper thermal pad for enhanced heat dissipation. The device has two terminals: Anode and Cathode - both anodes must be connected per datasheet layout guidance for optimal surge current sharing.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (pins 1 & 2) | Surge current entry point | Internally paralleled anodes accept bidirectional transients; requires PCB copper pour connection to chassis ground |
| Cathode (pin 3) | Surge current return path | Connected to protected circuit's power rail (e.g., 12 V battery line); forms clamping loop with anode |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive use across temperature, humidity, and mechanical stress cycles - required for ECU front-end protection |
| ISO 7637-2 Pulse 5a/b compliance | Withstands −150 V (Pulse 5a) and +112 V (Pulse 5b) load-dump surges with <100 ns response time - eliminates need for external crowbar circuits |
| Low αT coefficient | 10 × 10−4/°C - ensures stable clamping voltage over full −55 to +175 °C operating range, critical for under-hood reliability |
| D²PAK thermal performance | Rth(j-c) = 0.24 °C/W - enables >90% of rated pulse power to be dissipated through heatsink interface, not ambient air |
Applications
| Engine Control Unit (ECU) Power Input | Body Control Module (BCM) Battery Rail |
|---|---|
|
Use Scenario: Protects microcontroller power supply against alternator load-dump transients during battery disconnection while engine runs. IC Role / Device Role: Primary bidirectional clamping device placed between battery feed and DC-DC input stage. Use Value: Limits voltage to ≤71 V during 1000 A surge, preventing damage to downstream 40 V-rated MOSFETs and LDOs. |
Use Scenario: Shields BCM logic and CAN transceivers from ISO 16750-2 Test A/B surges during jump-start or battery replacement. IC Role / Device Role: Standoff protector on 12 V main rail upstream of power management ICs. Use Value: Maintains <1 µA leakage at 36 V, avoiding battery drain in sleep mode while clamping to 71 V at 1000 A. |
| Infotainment System Power Supply | ADAS Camera Module Input Protection |
|
Use Scenario: Guards USB-C PD controller and display driver ICs from reverse-polarity jump-start events and ISO 7637-2 Pulse 3b. IC Role / Device Role: First-line transient suppressor on fused 12 V input before buck converter. Use Value: Delivers 1000 W peak power handling with 0.24 °C/W thermal resistance, enabling compact heatsink design. |
Use Scenario: Secures 12 V input of 77 GHz radar camera module against load-dump pulses during vehicle start-stop cycling. IC Role / Device Role: Automotive-grade TVS integrated into camera housing PCB near connector. Use Value: AEC-Q101 qualification and 175 °C Tjmax ensure uninterrupted operation in sealed, high-temp enclosures. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar automotive TVS protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ43A | Unidirectional, SMA package, VBR = 47.8–52.8 V, VCL = 69.4 V @ 11.3 A (8/20 µs), PPP = 400 W | Limited to single-polarity surges; insufficient for ISO 7637-2 Pulse 5b (+112 V) without series diode | Select only for cost-sensitive non-AEC-Q101 applications with lower surge energy requirements |
| SMCJ43A | Unidirectional, SMC package, VBR = 47.8–52.8 V, VCL = 69.4 V @ 43.3 A (8/20 µs), PPP = 1500 W | Higher power rating but unidirectional; lacks AEC-Q101 certification and 175 °C rating | Use where higher peak power is needed but automotive qualification and bidirectional clamping are not mandatory |
Compared with SMAJ43A and SMCJ43A, the LDP01-42AY uniquely combines bidirectional clamping, AEC-Q101 qualification, 175 °C operation, and D²PAK thermal performance - making it the only drop-in solution for ISO 7637-2-compliant front-end protection in production automotive ECUs.
Availability
LDP01-42AY is available at Aetrix Electronics and suitable for engine control units, body control modules, and infotainment power supplies requiring stable component supply across multi-year automotive production programs.
Supply support for LDP01-42AY 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, designing and manufacturing analog, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.
The LDP01-xxAY series belongs to ST's Transil™ automotive TVS portfolio, engineered specifically to replace legacy Zener-based solutions with planar avalanche diodes that meet ISO 7637-2 and ISO 16750-2 load-dump immunity requirements.
FAQ
What is the recommended PCB layout for LDP01-42AY to achieve optimal thermal performance?
Mount the D²PAK package directly onto a ≥25 mm² copper pour connected to internal ground plane via ≥4 thermal vias (0.3 mm diameter, spaced ≤1.5 mm apart). Keep anode and cathode traces short and wide (≥1.5 mm width) to minimize inductance and ensure sub-100 ns response. Avoid solder mask over thermal pad.
Does LDP01-42AY require external series impedance for ISO 7637-2 Pulse 5a/b compliance?
No. The LDP01-42AY is characterized and validated to meet ISO 7637-2 Pulse 5a (−150 V) and 5b (+112 V) without external series resistance. Its 71 V clamping voltage at 1000 A (8/20 µs) inherently satisfies the standard's voltage limits when placed directly on the protected line.
How does the 175 °C maximum junction temperature impact long-term reliability in under-hood applications?
Rated Tjmax = 175 °C allows continuous operation in ambient temperatures up to 125 °C when combined with proper heatsinking (Rth(j-c) = 0.24 °C/W). This extends FIT rate beyond 1000 years at 105 °C ambient, satisfying ASIL-B functional safety requirements for power rail protection.
Can LDP01-42AY be used in 48 V mild-hybrid systems?
No. The LDP01-42AY is specified for 12 V/24 V automotive systems (VRM = 36 V, VBR = 42 V). For 48 V architectures, ST recommends the LDP01-68AY (VBR = 68 V) or LDP01-82AY (VBR = 82 V), both sharing identical D²PAK packaging and AEC-Q101 qualification.
LDP01-42AY Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- TO-263-3, D2PAK (2 Leads + Tab), TO-263AB
- Series:
- LDP01Y, TRANSIL™
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 36V
- Voltage - Breakdown (Min):
- 40V
- Voltage - Clamping (Max) @ Ipp:
- 57V
- Current - Peak Pulse (10/1000µs):
- 77A
- Power - Peak Pulse:
- -
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- D2PAK
LDP01-42AY FAQ
1.How can I place an order for LDP01-42AY through Aetrix?
Please submit a Request for Quotation (RFQ) for LDP01-42AY 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 LDP01-42AY reliable?
The price and inventory of LDP01-42AY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LDP01-42AY is usually 5 days.
3.What payment methods are accepted for LDP01-42AY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LDP01-42AY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LDP01-42AY?
LDP01-42AY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LDP01-42AY 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 LDP01-42AY?
For technical support, including LDP01-42AY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LDP01-42AY requirements.
6.How does Aetrix verify that LDP01-42AY is sourced from the original manufacturer or authorized distributors?
All LDP01-42AY 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 LDP01-42AY meets industry standards.
7.What is the process for return or replacement of LDP01-42AY?
All LDP01-42AY units undergo pre-shipment inspection (PSI). If there is an issue with LDP01-42AY, 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 LDP01-42AY part is unused and in its original packaging.
Return procedure for LDP01-42AY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LDP01-42AY Tags
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