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Vishay Semiconductor Opto Division TLLY4401
- Part No.:
- TLLY4401
- Manufacturer:
- Vishay Semiconductor Opto Division
- Category:
- LED Indication - Discrete
- Package:
- Radial
- Datasheet:
-
TLLY4401.pdf
- Description:
- LED YELLOW DIFFUSED T-1 T/H
- Quantity:
- Payment:
- Shipping:
Inventory:4,726
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Product details
Overview
TLLY4401 from Vishay Semiconductors is a low-current yellow LED in a 3 mm tinted diffused package, specified at 2 mA forward current, with luminous intensity of 1–2 mcd, dominant wavelength 581–594 nm, and forward voltage 2.4–2.9 V. It serves as an indicator in ultra-low-power DC circuits where visual status signaling is required under constrained energy budgets.
For engineers reviewing the TLLY4401 datasheet, TLLY4401 pinout, TLLY4401 application, or TLLY4401 equivalent, key selection criteria include its 3 mm through-hole package geometry, ±25° viewing angle, GaAsP-on-GaP die technology, and compliance with luminous intensity binning (Group L), making it suitable for consistent visual feedback in battery-powered instrumentation and legacy control panels.
Technical Context
This device operates as a standard polarity (anode/cathode) visible-light emitter with no internal circuitry-functionally a two-terminal passive optoelectronic component. Its optical output is characterized at 2 mA pulsed (25 ms), with junction capacitance ≤50 pF and thermal resistance of 800 K/W, enabling stable operation up to +100°C ambient.
Designed for low-power DC biasing, the TLLY4401 exhibits forward voltage hysteresis typical of GaAsP-based LEDs and maintains luminous intensity consistency within ±25° half-intensity angle. Its absolute maximum ratings-7 mA DC forward current, 6 V reverse voltage, and 20 mW power dissipation-define safe operating boundaries for discrete indicator use without series resistor recalculations beyond standard 2 mA drive.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Luminous intensity | 1–2 mcd at 2 mA - defines minimum visible brightness under nominal low-current drive |
| Dominant wavelength | 581–594 nm - specifies yellow chromaticity compliant with Group 1–6 color bins per Vishay classification |
| Forward voltage | 2.4–2.9 V at 2 mA - determines minimum supply headroom and series resistor value for 2 mA bias |
| Viewing angle | ±25° - sets angular visibility envelope for front-panel indicator placement |
| Absolute max forward current | 7 mA - establishes upper limit for transient or margin testing without degradation |
| Junction-to-ambient thermal resistance | 800 K/W - indicates self-heating magnitude under continuous 2 mA operation in still air |
| Package type | Ø3 mm tinted diffused - defines mechanical footprint, light diffusion profile, and PCB mounting compatibility |
Pinout & Package
Package: Ø3 mm radial-leaded, tinted diffused epoxy lens with cathode-indicating flat side and shorter lead. Standard through-hole mounting with 2.54 mm lead spacing.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (longer lead) | Positive terminal | Connects to current source or pull-up; must be biased >2.4 V above cathode to emit |
| Cathode (shorter lead, flat side) | Negative terminal | Reference node for current return; identifies polarity during manual placement |
Key Features
| Feature | Design Value |
|---|---|
| Low power consumption | Rated at 2 mA-enables direct microcontroller GPIO driving without external current limiting in many cases |
| High brightness per mA | 1–2 mcd @ 2 mA-delivers visible indication from sub-5 mW input power, critical for coin-cell devices |
| CMOS/MOS compatible | No reverse breakdown risk below 6 V-safe for interfacing with logic-level outputs and open-drain drivers |
| Luminous intensity binning | Group L (1–2 mcd)-ensures uniform brightness across production lots for multi-LED panels |
| Color categorization | Yellow wavelength binned into Groups 1–6-supports precise chromatic matching in multi-color status arrays |
Applications
| Industrial Control Panel Indicator | Portable Medical Device Status Light |
|---|---|
Use Scenario: Front-panel power-on and fault-state indication on DIN-rail mounted PLC I/O modules. IC Role / Device Role / Timing Role: Discrete visual status emitter-no timing or signal processing role; driven statically by 3.3 V MCU GPIO with 1 kΩ series resistor. Use Value: Maintains legible yellow glow at 2 mA under 40–85°C ambient, eliminating need for boost circuitry or high-brightness LEDs with excessive power draw. |
Use Scenario: Battery-operated glucose meter displaying measurement completion and low-battery warning. IC Role / Device Role / Timing Role: Human-interface optical output-activated for <500 ms per event; no clock or data function. Use Value: Delivers detectable yellow flash at 2 mA from 3 V CR2032 cell, extending operational life beyond 12 months with 10 activations/day. |
| Legacy Test Equipment Power Indicator | Automotive Aftermarket Diagnostic Tool UI |
Use Scenario: "Power Applied" lamp on benchtop multimeter or oscilloscope auxiliary units. IC Role / Device Role / Timing Role: Steady-state DC indicator-biased continuously during equipment operation; no modulation or PWM required. Use Value: Stable 2.4–2.9 V VF enables fixed-resistor bias design across 5 V or 3.3 V rails, reducing BOM count versus adjustable-current solutions. |
Use Scenario: OBD-II scanner showing connection status and active communication on vehicle dashboard. IC Role / Device Role / Timing Role: Ambient-light-readable status emitter-mounted behind tinted polycarbonate overlay. Use Value: ±25° viewing angle and diffused lens provide uniform illumination through 2 mm thick overlay without hotspots or glare. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LED indicator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TLLY4401-MS12 | Same luminous intensity, wavelength, and VF specs; differs only in tape packaging orientation (cathode-first feed) | Identical electrical/optical performance; selected when automated pick-and-place requires specific tape leader polarity | Choose TLLY4401-MS12 only if SMT line uses MS-coded tape reels; otherwise TLLY4401 is functionally identical |
| TLLY4400 | Luminous intensity lower (0.63–1.2 mcd vs. 1–2 mcd); same VF, wavelength, and package | Suitable where reduced brightness suffices-e.g., dark-room indicators or stacked-LED arrays requiring intensity grading | Select TLLY4400 when lower visual intensity is acceptable to reduce current load or enable tighter binning control |
Compared with TLLY4401, TLLY4401-MS12 offers identical optoelectrical behavior but different reel orientation for SMT assembly, while TLLY4400 provides lower luminous intensity at same drive conditions-making it appropriate for applications where reduced brightness improves readability or eases current budgeting.
Availability
TLLY4401 is available at Aetrix Electronics and suitable for industrial control panels, portable medical diagnostics, legacy test equipment, and automotive aftermarket tools requiring stable component supply with consistent luminous output and long-term obsolescence management.
Supply support for TLLY4401 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
Vishay Intertechnology is a global semiconductor manufacturer specializing in discrete components, sensors, and passive elements, with emphasis on reliability, precision, and long-lifecycle support.
The TLLY4401 belongs to Vishay's low-current LED product line, engineered specifically for energy-constrained indicator applications where consistent color, low drive current, and mechanical robustness in 3 mm packages are prioritized over high-output or surface-mount form factors.
FAQ
What is the maximum continuous forward current rating for TLLY4401?
The TLLY4401 has an absolute maximum DC forward current rating of 7 mA at 25°C ambient. Operation at its rated 2 mA ensures long-term reliability and stable luminous output; exceeding 7 mA risks irreversible degradation of the GaAsP-on-GaP die even with short-duration pulses. Always verify PCB trace current capacity and series resistor power rating when designing for worst-case thermal conditions.
Does TLLY4401 require a current-limiting resistor in a 3.3 V circuit?
Yes, TLLY4401 requires a current-limiting resistor when driven from a 3.3 V supply. With a typical forward voltage of 2.4–2.9 V at 2 mA, a 220 Ω resistor yields ~2.3 mA-within specification and providing margin against VF variation. Omitting the resistor risks exceeding the 7 mA absolute maximum rating and rapid failure due to thermal runaway.
Is TLLY4401 compatible with reflow soldering processes?
No, TLLY4401 is not reflow-solder compatible. It is a through-hole device with epoxy lens rated for wave or hand soldering only. The maximum soldering temperature is 260°C for ≤5 seconds at 2 mm from the body. Reflow profiles exceed this thermal limit and will crack the lens or delaminate the die bond. Use only wave or selective soldering for TLLY4401.
What does the "L" bin designation mean for TLLY4401 luminous intensity?
The "L" bin for TLLY4401 indicates a luminous intensity range of 1–2 mcd at 2 mA, per Vishay's standardized brightness categorization table. This bin ensures uniform visual output across all units shipped in a single bag-no mixing of intensity groups occurs. Designers selecting TLLY4401 can rely on this consistency for multi-LED interfaces without post-assembly sorting.
Can TLLY4401 be used in outdoor applications exposed to UV or moisture?
TLLY4401 is not rated for outdoor or harsh-environment use. Its tinted diffused epoxy package provides no IP-rated sealing, UV stabilization, or moisture resistance. Prolonged UV exposure causes yellowing and output decay; humidity ingress may lead to leakage or corrosion. For outdoor use, select Vishay's AEC-Q200 qualified or hermetically sealed LED alternatives instead of TLLY4401.
TLLY4401 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay Semiconductor Opto Division
- Series:
- -
- Package/Case:
- Radial
- Packaging:
- Bulk
- Product Status:
- Active
- Color:
- Yellow
- Configuration:
- Standard
- Lens Color:
- -
- Lens Transparency:
- Diffused
- Millicandela Rating:
- 2mcd
- Lens Style:
- Round with Domed Top
- Lens Size:
- 3.20mm Dia
- Voltage - Forward (Vf) (Typ):
- 2.4V
- Current - Test:
- 2mA
- Viewing Angle:
- 50°
- Mounting Type:
- Through Hole
- Wavelength - Dominant:
- 588nm
- Wavelength - Peak:
- 585nm
- Features:
- -
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- T-1
- Size / Dimension:
- -
TLLY4401 FAQ
1.How can I place an order for TLLY4401 through Aetrix?
Please submit a Request for Quotation (RFQ) for TLLY4401 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 TLLY4401 reliable?
The price and inventory of TLLY4401 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TLLY4401 is usually 5 days.
3.What payment methods are accepted for TLLY4401?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TLLY4401 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TLLY4401?
TLLY4401 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TLLY4401 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 TLLY4401?
For technical support, including TLLY4401 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TLLY4401 requirements.
6.How does Aetrix verify that TLLY4401 is sourced from the original manufacturer or authorized distributors?
All TLLY4401 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 TLLY4401 meets industry standards.
7.What is the process for return or replacement of TLLY4401?
All TLLY4401 units undergo pre-shipment inspection (PSI). If there is an issue with TLLY4401, 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 TLLY4401 part is unused and in its original packaging.
Return procedure for TLLY4401:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TLLY4401 Tags
-
LTST-C281KRKT
Lite-On Inc.
-
150060GS75000
Würth Elektronik
-
150060VS75000
Würth Elektronik
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150060AS75000
Würth Elektronik
-
150060YS75000
Würth Elektronik
-
150060SS75000
Würth Elektronik
-
150060BS75000
Würth Elektronik
-
151031VS06000
Würth Elektronik
-
151033RS03000
Würth Elektronik
-
150080BS75000
Würth Elektronik
-
150080GS75000
Würth Elektronik
-
150141GS73100
Würth Elektronik
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