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STMicroelectronics LDP01-50AY
- Part No.:
- LDP01-50AY
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- TO-263-3, D2PAK (2 Leads + Tab), TO-263AB
- Datasheet:
-
LDP01-50AY.pdf
- Description:
- TVS DIODE 43VWM 68VC D2PAK
- Quantity:
- Payment:
- Shipping:
Inventory:1,772
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Product details
Overview
LDP01-50AY from STMicroelectronics is an automotive-grade transient voltage suppression (TVS) diode designed for load-dump protection in 12 V and 24 V vehicle electrical systems. It features a 50 V nominal breakdown voltage (47.8–52.8 V), 276 A peak pulse current (8/20 µs), 81 V clamping voltage at rated surge, 1 µA leakage at 43 V, and operates up to 175 °C junction temperature. It is used in alternator output line protection for engine control units and body control modules.
For engineers reviewing the LDP01-50AY datasheet, LDP01-50AY pinout, LDP01-50AY application, or LDP01-50AY equivalent, key selection criteria include ISO 7637-2 Pulse 5a/5b compliance, clamping performance under 175 °C thermal stress, D²PAK package thermal resistance (0.24 °C/W), and AEC-Q101 qualification for under-hood deployment.
Technical Context
The LDP01-50AY employs planar silicon avalanche technology optimized for high-energy load-dump transients defined in ISO 7637-2 (Pulse 5a/5b) and ISO 16750-2 (Tests A/B). Its low dynamic impedance (31 mΩ) ensures stable clamping during multi-kW surges up to 10 ms duration.
It operates with bidirectional conduction capability and requires both anodes connected to ground per datasheet layout guidance. The device's voltage temperature coefficient (αT = 10.2 × 10−4/°C) enables predictable VBR and VCL drift across −55 °C to +175 °C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Breakdown Voltage (VBR) | 47.8–52.8 V at IR = 1 mA - defines minimum trigger threshold for load-dump clamping |
| Clamping Voltage (VCL) | 81 V at IPP = 276 A (8/20 µs) - maximum voltage seen by protected IC during worst-case surge |
| Peak Pulse Current | 276 A (8/20 µs), 55 A (10/1000 µs) - quantifies surge energy handling per waveform standard |
| Leakage Current | 1 µA at VRM = 43 V, 25 °C - ensures minimal standby power loss in always-on automotive circuits |
| Junction Temperature Range | −55 °C to +175 °C - supports placement near engines or power electronics without derating |
| Thermal Resistance (Rth(j-c)) | 0.24 °C/W - enables efficient heat transfer to heatsink or PCB copper in D²PAK package |
| AEC-Q101 Qualified | Yes - validated for automotive reliability including temperature cycling, HTRB, and ESD per stress test protocol |
Pinout & Package
Package: D²PAK (TO-263AB), surface-mount, single-row 3-lead outline with exposed thermal pad. JEDEC registered, UL94 V0 compliant epoxy, RoHS and halogen-free.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode 1 (Pin 1) | Surge input terminal | Connected to battery/alternator line; must be routed with low-inductance path to minimize overshoot |
| Anode 2 (Pin 2) | Surge input terminal | Electrically tied to Anode 1 internally; both pins require equal-length PCB traces per layout guidelines |
| Cathode (Pin 3) | Reference/ground return | Connected directly to chassis or power ground plane; serves as clamping reference node |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional load-dump clamping | Protects against both positive and negative transients without external polarity configuration |
| High-temperature operation (Tj(max) = 175 °C) | Eliminates need for thermal derating in under-hood environments where ambient exceeds 125 °C |
| Low dynamic impedance (31 mΩ) | Reduces clamping voltage rise under high di/dt, improving margin for 5 V or 3.3 V downstream logic |
| ISO 7637-2 Pulse 5a/5b compliance | Validated for 150 V (P5a) and 87 V (P5b) load-dump events with variable series resistance (0.5–2 Ω) |
| JEDEC-standard D²PAK footprint | Enables drop-in replacement and thermal design reuse across ST's Transil™ TVS portfolio |
Applications
| Engine Control Unit (ECU) Power Input | Body Control Module (BCM) Battery Interface |
|---|---|
Use Scenario: Protects microcontroller power rails from alternator load-dump surges during battery disconnection while engine runs. IC Role / Device Role / Timing Role: Primary overvoltage clamp on main 12 V input rail upstream of DC-DC converters. Use Value: Limits voltage to ≤81 V during 300 ms, 70 V surge, preventing damage to 36 V-rated input capacitors and LDOs. | Use Scenario: Shields LIN bus transceivers and CAN PHY power supplies from battery-line transients in door modules and lighting nodes. IC Role / Device Role / Timing Role: Secondary surge suppressor placed after main fuse, before local regulators. Use Value: Maintains <1 µA leakage at 13.5 V nominal, avoiding sleep-current violations in always-on wake-up circuits. |
| ADAS Camera Power Supply | Electric Power Steering (EPS) Motor Driver |
Use Scenario: Secures image sensor and ISP power inputs in front-facing cameras exposed to under-hood thermal and electrical stress. IC Role / Device Role / Timing Role: First-line defense against ISO 16750-2 Test A (load dump) and Test B (superimposed ripple). Use Value: Clamps within 100 ns to hold VIN below 85 V, preserving 65 nm image signal chain integrity. | Use Scenario: Guards gate drivers and current-sense amplifiers in EPS motor control boards subjected to repeated cranking and load-dump events. IC Role / Device Role / Timing Role: High-power TVS placed across H-bridge supply rail (VBAT–GND). Use Value: Handles 276 A peak pulse without thermal runaway, verified at Tj = 175 °C per Figure 3. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar automotive load-dump protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ50A | Unidirectional, SMA package, Rth(j-c) ≈ 50 °C/W, VCL = 81.5 V @ 26.1 A (8/20 µs) | Lower surge rating (26 A vs. 276 A); suitable only for sub-100 W systems | Select when space-constrained and peak surge <50 A; not AEC-Q101 qualified. |
| SMCJ50A-Q | AEC-Q101 qualified, unidirectional, SMC package, VCL = 81.5 V @ 123 A (8/20 µs) | Half the peak current rating; lacks dual-anode configuration for symmetric layout | Choose for cost-sensitive AEC-Q101 designs where 123 A surge margin suffices and dual-anode routing is unnecessary. |
Compared with SMAJ50A and SMCJ50A-Q, the LDP01-50AY delivers 2.2× higher surge current capacity, integrated dual-anode symmetry for balanced PCB layout, and superior thermal performance (0.24 °C/W vs. >10 °C/W), making it uniquely suited for high-power automotive power rails.
Availability
LDP01-50AY is available at Aetrix Electronics and suitable for engine control units, body control modules, and ADAS camera power supplies requiring stable component supply across extended temperature and high-reliability automotive programs.
Supply support for LDP01-50AY 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, MCU, power, and automotive ICs for industrial, automotive, and consumer markets.
The LDP01-xxAY series belongs to ST's Transil™ TVS portfolio, engineered specifically for robust load-dump protection in automotive power networks where high junction temperature, low leakage, and standardized D²PAK thermal performance are mandatory.
FAQ
What is the recommended PCB layout for LDP01-50AY to ensure optimal clamping performance?
Both anodes (Pins 1 and 2) must be connected with identical trace length and width to the battery line, and the cathode (Pin 3) must connect directly to a low-impedance ground plane. Thermal pad soldering is mandatory; minimum 80% coverage with thermal vias to inner ground layers is required to achieve Rth(j-c) = 0.24 °C/W.
Does LDP01-50AY meet ISO 16750-2 Test A and Test B requirements?
Yes - the device is explicitly characterized for both tests in Figures 9–12 of the datasheet. It clamps Test A (load dump, Us = 30–75 V) and Test B (superimposed ripple, Us* = 20–65 V) across serial resistances of 0.5–2 Ω and time durations of 150–400 ms.
Can LDP01-50AY be used in 24 V commercial vehicle systems?
Yes - its 50 V VBR and 81 V VCL provide sufficient margin above 24 V nominal (typically 27–28 V running) and withstand ISO 7637-2 Pulse 5a up to 150 V, making it suitable for trucks, buses, and off-highway equipment with higher battery voltages.
How does temperature affect the clamping voltage of LDP01-50AY?
VCL increases linearly with junction temperature using αT = 10.2 × 10−4/°C. At 175 °C, VCL rises ~1.5 V above its 25 °C value (81 V → ~82.5 V), remaining well within safe limits for 85 V-rated downstream components.
LDP01-50AY 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):
- 43V
- Voltage - Breakdown (Min):
- 47.8V
- Voltage - Clamping (Max) @ Ipp:
- 68V
- Current - Peak Pulse (10/1000µs):
- 55A
- 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
LDP01-50AY FAQ
1.How can I place an order for LDP01-50AY through Aetrix?
Please submit a Request for Quotation (RFQ) for LDP01-50AY 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 LDP01-50AY reliable?
The price and inventory of LDP01-50AY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LDP01-50AY is usually 5 days.
3.What payment methods are accepted for LDP01-50AY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LDP01-50AY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LDP01-50AY?
LDP01-50AY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LDP01-50AY 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 LDP01-50AY?
For technical support, including LDP01-50AY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LDP01-50AY requirements.
6.How does Aetrix verify that LDP01-50AY is sourced from the original manufacturer or authorized distributors?
All LDP01-50AY 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 LDP01-50AY meets industry standards.
7.What is the process for return or replacement of LDP01-50AY?
All LDP01-50AY units undergo pre-shipment inspection (PSI). If there is an issue with LDP01-50AY, 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 LDP01-50AY part is unused and in its original packaging.
Return procedure for LDP01-50AY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LDP01-50AY Tags
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