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Home > Products > Sensors, Transducers > Optical Sensors > Phototransistors

Vishay Semiconductor Opto Division VEMT2523SLX01

Name: VEMT2523SLX01
Brand: Vishay Semiconductor Opto Division
SKU: VEMT2523SLX01
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: VEMT2523SLX01

Manufacturer:: Vishay Semiconductor Opto Division

Category:: Phototransistors

Package:: 2-SMD, Side View

Datasheet:: VEMT2523SLX01.pdf

Description:: PHOTOTRANSISTOR 470 TO 1090 NM

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Product details

Overview

VEMT2523SLX01 from Vishay Semiconductors is a silicon NPN epitaxial planar phototransistor in a miniature side-view surface-mount package with clear epoxy dome lens, delivering 2.7 mA typical collector light current at 950 nm, ±35° angle of half sensitivity, and spectral response from 470 nm to 1090 nm. It is AEC-Q101 qualified and used in automotive position sensors and photo interrupters.

For engineers reviewing the VEMT2523SLX01 datasheet, VEMT2523SLX01 pinout, VEMT2523SLX01 application, or VEMT2523SLX01 equivalent, key selection criteria include radiant sensitivity at 950 nm, angular response profile, thermal coefficient of Ica (1.1 %/K), and compatibility with Vishay's VSMB2943SLX01 IR emitter series.

Technical Context

The VEMT2523SLX01 operates as a light-controlled NPN transistor with collector-emitter breakdown voltage of 20 V and dark current ≤100 nA at 5 V. Its spectral peak sensitivity occurs at 850 nm, with usable bandwidth spanning visible (470 nm) to near-infrared (1090 nm) radiation.

Thermal performance is defined by junction-to-ambient thermal resistance of 250 K/W and operating ambient temperature range of −40 °C to +100 °C. Rise/fall times are under 20 µs at IC = 100 µA with RL = 100 Ω, supporting fast optical switching in encoder and counter applications.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	20 V - Maximum collector-emitter voltage before breakdown; sets upper limit for biasing in 5 V or 12 V optical detection circuits.
I_ca (typ)	2.7 mA at E_e = 1 mW/cm², λ = 950 nm - Defines signal output level under standard IR illumination; enables direct interfacing with logic-level inputs without amplification.
Angle of half sensitivity	±35° - Optical field-of-view constrains mechanical alignment tolerance in slot-type photo interrupters and proximity sensing.
Spectral bandwidth	470–1090 nm - Supports dual-use with visible LEDs (e.g., 630 nm) and NIR emitters (e.g., 850 nm or 940 nm), enabling flexible source pairing.
T_j max	100 °C - Junction temperature limit governs maximum power dissipation (100 mW at T_amb ≤ 75 °C) in sealed automotive enclosures.
R_thJA	250 K/W - Thermal resistance determines self-heating rise per mW; critical for stability in high-duty-cycle pulsed operation.
MSL Level	2a - Requires moisture-sensitive handling: floor life 4 weeks at <30 °C / <60 % RH; mandates bake-out if exposed beyond limit.

Pinout & Package

Package: Miniature side-view SMD with clear epoxy dome lens; dimensions 2.3 mm × 2.55 mm × 2.3 mm (L × W × H); tape-and-reel packaging (3000 pcs/reel).

Pin/Terminal	Circuit Role	Design Meaning
Collector	Output current terminal	Carries light-generated collector current; connected to pull-up resistor or load; polarity defines NPN active region operation.
Emitter	Reference terminal	Common node for biasing; tied to ground or low-side switch; establishes V_CE across device during conduction.

Key Features

Feature	Design Value
AEC-Q101 qualification	Validated for automotive-grade reliability including temperature cycling, humidity testing, and mechanical shock per JESD22 standards.
Side-view optical geometry	Enables compact PCB layout in edge-detect configurations; lens orientation aligns with perpendicular emitter placement in slotted housings.
High radiant sensitivity	Delivers 2.7 mA output under 1 mW/cm² irradiance at 950 nm-reduces required LED drive current and extends battery life in portable systems.
Fast response time	Rise/fall times <20 µs at 100 µA enable >10 kHz optical pulse detection in rotary encoders and high-speed counting.
Matched emitter pairing	Optimized for use with Vishay VSMB2943SLX01 IR emitter-ensures spectral overlap, mechanical alignment, and thermal co-location in integrated modules.

Applications

Automotive Position Sensing	Photo Interrupter
Use Scenario: Detecting gear tooth passage or camshaft rotation in engine control units using slotted metal discs. IC Role / Device Role / Timing Role: Light-controlled switch providing digital edge transitions synchronized to mechanical motion. Use Value: ±35° angular tolerance accommodates mounting misalignment; AEC-Q101 rating ensures operation at 100 °C under hood.	Use Scenario: Object presence detection in printer paper path or vending machine dispensing mechanism. IC Role / Device Role / Timing Role: Transmissive optical switch generating logic-level output when beam is unbroken. Use Value: 2.7 mA output drives standard CMOS inputs directly; side-view package allows narrow slot design with minimal PCB footprint.
Rotary Encoder	Miniature Limit Switch
Use Scenario: Quadrature signal generation from rotating shaft with alternating opaque/transparent segments on encoder disk. IC Role / Device Role / Timing Role: High-speed photodetector capturing position and direction via dual-channel phase-shifted outputs. Use Value: Sub-20 µs rise/fall time supports >10 kHz edge rates; 470–1090 nm bandwidth accepts multiple emitter wavelengths for redundancy.	Use Scenario: End-of-travel detection in linear actuators or robotic joints where space constraints prohibit mechanical switches. IC Role / Device Role / Timing Role: Non-contact solid-state switch replacing microswitches in high-cycle, dust-prone environments. Use Value: Clear epoxy lens resists contamination; MSL 2a handling ensures robustness during automated assembly of compact modules.

Automotive Position Sensing

Photo Interrupter

Use Scenario: Detecting gear tooth passage or camshaft rotation in engine control units using slotted metal discs.

IC Role / Device Role / Timing Role: Light-controlled switch providing digital edge transitions synchronized to mechanical motion.

Use Value: ±35° angular tolerance accommodates mounting misalignment; AEC-Q101 rating ensures operation at 100 °C under hood.

Use Scenario: Object presence detection in printer paper path or vending machine dispensing mechanism.

IC Role / Device Role / Timing Role: Transmissive optical switch generating logic-level output when beam is unbroken.

Use Value: 2.7 mA output drives standard CMOS inputs directly; side-view package allows narrow slot design with minimal PCB footprint.

Rotary Encoder

Miniature Limit Switch

Use Scenario: Quadrature signal generation from rotating shaft with alternating opaque/transparent segments on encoder disk.

IC Role / Device Role / Timing Role: High-speed photodetector capturing position and direction via dual-channel phase-shifted outputs.

Use Value: Sub-20 µs rise/fall time supports >10 kHz edge rates; 470–1090 nm bandwidth accepts multiple emitter wavelengths for redundancy.

Use Scenario: End-of-travel detection in linear actuators or robotic joints where space constraints prohibit mechanical switches.

IC Role / Device Role / Timing Role: Non-contact solid-state switch replacing microswitches in high-cycle, dust-prone environments.

Use Value: Clear epoxy lens resists contamination; MSL 2a handling ensures robustness during automated assembly of compact modules.

Equivalent & Alternatives

The following parts are listed as comparable options for similar phototransistor detection applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
VEMT2023SLX01	Lower I_ca (1.8 mA typ), same package and spectral range; reduced radiant sensitivity due to different die process.	Suitable for lower-light environments or where signal margin is less critical; not recommended for high-speed (>5 kHz) or low-irradiance applications.	Select when cost sensitivity outweighs speed/sensitivity requirements; verify optical path irradiance meets 1.8 mA threshold.
QSE159	Through-hole TO-92 package; I_ca = 2.0 mA typ at 850 nm; no AEC-Q101 qualification; wider ±50° viewing angle.	Used in legacy industrial controls and prototyping; lacks automotive qualification and SMD compatibility.	Choose only for hand-soldered or non-automotive designs where board space and qualification are secondary to availability.

Compared with VEMT2523SLX01, VEMT2023SLX01 trades sensitivity for cost in identical SMD form, while QSE159 offers broader angular coverage but sacrifices automotive compliance and surface-mount integration-making VEMT2523SLX01 optimal for space-constrained, high-reliability optical sensing.

Availability

VEMT2523SLX01 is available at Aetrix Electronics and suitable for automotive position sensors, photo interrupters, rotary encoders, and miniature limit switches requiring stable component supply, AEC-Q101 compliance, and consistent optical performance across temperature.

Supply support for VEMT2523SLX01 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 Semiconductors is a global leader in discrete semiconductors, specializing in optoelectronics, power MOSFETs, diodes, and precision resistors with emphasis on reliability and automotive-grade validation.

The VEMT2523SLX01 belongs to Vishay's VEMT series of high-sensitivity silicon phototransistors designed specifically for compact, high-speed, and AEC-Q101-compliant optical sensing in automotive and industrial motion control systems.

FAQ

What is the peak wavelength sensitivity of the VEMT2523SLX01?

The VEMT2523SLX01 has a peak wavelength sensitivity (λ_p) of 850 nm, with usable spectral response spanning 470 nm to 1090 nm. This makes the VEMT2523SLX01 compatible with both visible red LEDs and near-infrared emitters, and its 850 nm peak aligns closely with common IR sources like the VSMB2943SLX01, ensuring optimal signal-to-noise ratio in matched-pair configurations.

Is the VEMT2523SLX01 suitable for automotive applications?

Yes, the VEMT2523SLX01 is AEC-Q101 qualified and rated for operation from −40 °C to +100 °C ambient temperature, with junction temperature up to 100 °C. Its construction, thermal resistance (250 K/W), and reliability testing meet automotive requirements, making the VEMT2523SLX01 appropriate for under-hood position sensing, transmission feedback, and body control module optical interfaces.

What is the maximum collector current rating for the VEMT2523SLX01?

The absolute maximum collector current (I_C) for the VEMT2523SLX01 is 50 mA, though typical operating collector light current (I_ca) is 2.7 mA under standard test conditions (E_e = 1 mW/cm², λ = 950 nm, V_CE = 5 V). Exceeding 50 mA risks permanent damage; sustained operation above 2.7 mA requires careful thermal derating per the power dissipation curve.

Does the VEMT2523SLX01 have a built-in lens, and what is its viewing angle?

Yes, the VEMT2523SLX01 features a clear epoxy dome lens optimized for side-view optical coupling. Its angle of half sensitivity is ±35°, meaning radiant sensitivity drops to 50% at 35° off-axis. This directional response improves noise immunity in multi-source environments and simplifies mechanical alignment in slotted interrupter housings.

What is the moisture sensitivity level (MSL) and floor life of the VEMT2523SLX01?

The VEMT2523SLX01 is rated MSL 2a per J-STD-020, with a floor life of 4 weeks when stored at <30 °C and <60 % relative humidity. Once removed from the moisture barrier bag, the VEMT2523SLX01 must be assembled within that window or baked per J-STD-020 guidelines (e.g., 192 h at 40 °C, RH < 5 %) before reflow soldering.

VEMT2523SLX01 Specifications

Product attributes: Attribute value

Manufacturer:: Vishay Semiconductor Opto Division

Series:: -

Package/Case:: 2-SMD, Side View

Packaging:: Tape & Reel (TR)

Product Status:: Active

Voltage - Collector Emitter Breakdown (Max):: 20 V

Current - Collector (Ic) (Max):: 50 mA

Current - Dark (Id) (Max):: 1 nA

Wavelength:: 850nm

Viewing Angle:: 70°

Power - Max:: 100 mW

Mounting Type:: Surface Mount, Right Angle

Orientation:: Side View

Operating Temperature:: -40°C ~ 100°C

Grade:: Automotive

Qualification:: AEC-Q101

VEMT2523SLX01 FAQ

1.How can I place an order for VEMT2523SLX01 through Aetrix?

Please submit a Request for Quotation (RFQ) for VEMT2523SLX01 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 VEMT2523SLX01 reliable?

The price and inventory of VEMT2523SLX01 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for VEMT2523SLX01 is usually 5 days.

3.What payment methods are accepted for VEMT2523SLX01?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for VEMT2523SLX01 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for VEMT2523SLX01?

VEMT2523SLX01 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your VEMT2523SLX01 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 VEMT2523SLX01?

For technical support, including VEMT2523SLX01 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your VEMT2523SLX01 requirements.

6.How does Aetrix verify that VEMT2523SLX01 is sourced from the original manufacturer or authorized distributors?

All VEMT2523SLX01 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 VEMT2523SLX01 meets industry standards.

7.What is the process for return or replacement of VEMT2523SLX01?

All VEMT2523SLX01 units undergo pre-shipment inspection (PSI). If there is an issue with VEMT2523SLX01, 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 VEMT2523SLX01 part is unused and in its original packaging.

Return procedure for VEMT2523SLX01:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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