My Inquiry
My Account
Taiwan Semiconductor Corporation LL5818 L0G
- Part No.:
- LL5818 L0G
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- Single Diodes
- Package:
- DO-213AB, MELF
- Datasheet:
-
LL5818 L0G.pdf
- Description:
- DIODE SCHOTTKY 30V 1A MELF
- Quantity:
- Payment:
- Shipping:
Inventory:9,762
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LL5818 L0G from Taiwan Semiconductor is a 1A, 30V Schottky barrier surface-mount rectifier in MELF package, optimized for high-efficiency DC/DC conversion with low forward voltage (0.55 V at 1 A) and 25 A surge capability. It serves as a primary output rectifier in AC-DC adapters and isolated DC-DC converters operating up to 125°C junction temperature.
For engineers reviewing the LL5818 L0G datasheet, LL5818 L0G pinout, LL5818 L0G application, or LL5818 L0G equivalent, key selection criteria include repetitive peak reverse voltage (30 V), thermal resistance (80 °C/W), junction capacitance (110 pF), and RoHS/halogen-free compliance for industrial power supply design.
Technical Context
This Schottky rectifier uses a single-die construction in a glass-passivated MELF case, enabling reliable operation under repetitive surge stress (8.3 ms half-sine, 25 A) and continuous 1 A forward current. Its low VF minimizes conduction loss in high-frequency switching topologies.
The device exhibits defined thermal performance (RθJA = 80 °C/W) and reverse leakage behavior (≤0.5 mA at 25°C, ≤5 mA at 100°C), supporting stable operation in thermally constrained adapter and converter PCB layouts without forced airflow.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRRM | 30 V - Maximum repetitive reverse blocking voltage; defines safe operating limit in flyback or forward converter secondary-side rectification |
| IF | 1 A - Continuous average forward current rating; determines minimum heatsinking requirement in ambient temperatures up to 75°C |
| IFSM | 25 A - Non-repetitive surge current (8.3 ms); supports inrush and transient overload handling in offline SMPS |
| VF @ 1 A | 0.55 V - Forward voltage drop at rated DC current; directly impacts conduction loss and efficiency in 12–24 V output stages |
| CJ | 110 pF - Junction capacitance at 4 V reverse bias; influences switching loss and EMI in >100 kHz converters |
| RθJA | 80 °C/W - Junction-to-ambient thermal resistance; used to calculate temperature rise on standard FR-4 PCB with minimal copper area |
| TJ max | 125 °C - Maximum allowable junction temperature; sets upper boundary for thermal design margin in sealed enclosures |
Pinout & Package
MELF (Metal Electrode Leadless Face) cylindrical package with axial cathode band marking; no discrete pins - terminals are the two circular end faces. Requires symmetric SMD pad layout per TSC recommended footprint (A = 4.8–5.5 mm length, B = 2.25–2.67 mm diameter).
Key Features
| Feature | Design Value |
|---|---|
| RoHS & halogen-free compliance | Meets IEC 61249-2-21; enables use in consumer electronics requiring strict material declarations |
| 25 A surge rating (8.3 ms) | Supports robust startup and fault tolerance in unregulated AC-DC adapters without external snubbing |
| Low 0.55 V forward drop @ 1 A | Reduces power dissipation by ~15% vs. comparable 40 V Schottkys, improving thermal headroom in compact designs |
| JESD201 Class 1A whisker resistance | Validated reliability for long-term storage and high-humidity environments in industrial power modules |
| 110 pF junction capacitance | Enables clean turn-off in 300–500 kHz flyback converters while limiting capacitive coupling noise |
Applications
| AC-DC Adapters | Isolated DC-DC Converters |
|---|---|
Use Scenario: Secondary-side rectification in 5–24 V, 10–30 W wall adapters with universal input (90–264 VAC). IC Role / Device Role / Timing Role: Primary output rectifier replacing fast recovery diodes to improve efficiency and reduce heat sink size. Use Value: 0.55 V forward drop lowers conduction loss by ≥0.15 W vs. silicon diodes, enabling passive cooling in space-constrained enclosures. | Use Scenario: Output rectification in 12 V or 24 V isolated DC-DC modules for industrial PLC I/O power rails. IC Role / Device Role / Timing Role: High-reliability Schottky rectifier in fixed-frequency forward or flyback topologies operating up to 500 kHz. Use Value: 25 A surge rating handles load-step transients without derating; 125°C max junction temperature supports operation in sealed control cabinets. |
| Inverters | LED Drivers |
Use Scenario: Freewheeling path in 12–48 V DC input inverters for solar micro-inverters and UPS battery interfaces. IC Role / Device Role / Timing Role: Low-loss anti-parallel path during MOSFET dead-time, minimizing voltage spikes and body-diode conduction. Use Value: 110 pF junction capacitance limits displacement current during fast switching edges, reducing gate drive stress and EMI. | Use Scenario: Constant-current output rectification in non-isolated buck-derived LED drivers for street lighting (24–48 V output). IC Role / Device Role / Timing Role: Efficient, low-noise output stage rectifier with minimal thermal drift over ambient range (−40°C to +85°C). Use Value: Stable 0.55 V VF across temperature ensures consistent current regulation accuracy without feedback compensation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Schottky rectifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SB130-E3/54 (Vishay) | 30 V VRRM, 1 A IF, VF = 0.55 V @ 1 A, DO-41 package (axial leaded) | Requires through-hole mounting and manual assembly; not suitable for automated SMT lines | Select when legacy board rework or prototyping with breadboard-compatible leads is needed |
| SS13 (ON Semiconductor) | 30 V VRRM, 1 A IF, VF = 0.5 V @ 1 A, SMA package (flat SMD) | Lower VF improves efficiency but SMA has higher RθJA (~120 °C/W); requires larger copper pour for thermal management | Select when lowest possible conduction loss is prioritized and PCB layout allows enhanced thermal pads |
Compared with SB130-E3/54 and SS13, the LL5818 L0G offers MELF's superior surge robustness and automated placement compatibility, while balancing VF, thermal resistance, and footprint constraints better than axial or flat SMD alternatives in high-volume adapter production.
Availability
LL5818 L0G is available at Aetrix Electronics and suitable for AC-DC adapters, isolated DC-DC converters, and LED drivers requiring stable component supply with full traceability and lifecycle support.
Supply support for LL5818 L0G 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
Taiwan Semiconductor Corporation (TSC) is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, serving global power and protection markets since 1979.
The LL5817–LL5819 series was developed specifically for cost-sensitive, high-reliability surface-mount rectification in consumer and industrial power supplies where MELF's ruggedness and thermal performance outweigh flat-package trade-offs.
FAQ
What is the maximum repetitive peak reverse voltage rating for LL5818 L0G?
The LL5818 L0G has a maximum repetitive peak reverse voltage (VRRM) of 30 V, as specified in the Absolute Maximum Ratings table. This value is fixed for the LL5818 variant and distinct from LL5817 (20 V) and LL5819 (40 V). It defines the highest continuous reverse-bias voltage the device can block without breakdown under normal operating conditions.
Does LL5818 L0G require a heatsink in typical 1 A applications?
LL5818 L0G typically does not require an external heatsink when operated at ≤1 A in still air, provided the PCB uses ≥1 cm² of 1 oz copper connected to both terminals. Its RθJA of 80 °C/W results in ~8°C rise above ambient at 1 A with minimal copper; thermal simulation or empirical testing is recommended for enclosed or high-ambient (>60°C) deployments.
Is LL5818 L0G compatible with lead-free reflow soldering processes?
Yes, LL5818 L0G is qualified for lead-free reflow soldering per J-STD-020. The MELF glass-passivated package withstands peak temperatures up to 260°C for 10 seconds. Reflow profile must comply with TSC's recommended thermal ramp rates and time-above-liquidus (TAL) limits to avoid mechanical stress or interfacial delamination.
How does the forward voltage of LL5818 L0G compare to LL5819 L0G at 1 A?
At 1 A and 25°C, LL5818 L0G has a maximum forward voltage of 0.550 V, while LL5819 L0G is rated at 0.600 V. This 50 mV difference reflects the trade-off between higher blocking voltage and increased series resistance in the epitaxial layer; LL5818 L0G delivers lower conduction loss where 30 V VRRM suffices.
Can LL5818 L0G be used as a direct replacement for LL5817 L0G in an existing design?
LL5818 L0G is physically identical to LL5817 L0G (same MELF package, dimensions, and polarity marking) and shares all thermal and mechanical specs, but its 30 V VRRM provides higher reverse margin. It can replace LL5817 L0G if the circuit's peak reverse voltage stays below 30 V; verify stress margins in worst-case line/load transients before substitution.
LL5818 L0G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Series:
- -
- Package/Case:
- DO-213AB, MELF
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Technology:
- Schottky
- Voltage - DC Reverse (Vr) (Max):
- 30 V
- Current - Average Rectified (Io):
- 1A
- Voltage - Forward (Vf) (Max) @ If:
- 875 mV @ 3 A
- Speed:
- Fast Recovery =< 500ns, > 200mA (Io)
- Reverse Recovery Time (trr):
- -
- Current - Reverse Leakage @ Vr:
- 500 µA @ 30 V
- Capacitance @ Vr, F:
- 110pF @ 4V, 1MHz
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- MELF
- Operating Temperature - Junction:
- -65°C ~ 125°C
LL5818 L0G FAQ
1.How can I place an order for LL5818 L0G through Aetrix?
Please submit a Request for Quotation (RFQ) for LL5818 L0G 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 LL5818 L0G reliable?
The price and inventory of LL5818 L0G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LL5818 L0G is usually 5 days.
3.What payment methods are accepted for LL5818 L0G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LL5818 L0G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LL5818 L0G?
LL5818 L0G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LL5818 L0G 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 LL5818 L0G?
For technical support, including LL5818 L0G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LL5818 L0G requirements.
6.How does Aetrix verify that LL5818 L0G is sourced from the original manufacturer or authorized distributors?
All LL5818 L0G 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 LL5818 L0G meets industry standards.
7.What is the process for return or replacement of LL5818 L0G?
All LL5818 L0G units undergo pre-shipment inspection (PSI). If there is an issue with LL5818 L0G, 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 LL5818 L0G part is unused and in its original packaging.
Return procedure for LL5818 L0G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LL5818 L0G 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
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…
