Table of Contents
- 1. Product Overview
- 2. Technical Specifications Deep Dive
- 2.1 Absolute Maximum Ratings
- 2.2 Electro-Optical Characteristics (Ta=25°C)
- 3. Performance Curve Analysis
- 3.1 Power Dissipation vs. Ambient Temperature
- 3.2 Spectral Sensitivity
- 3.3 Reverse Light Current vs. Irradiance
- 3.4 Dark Current vs. Ambient Temperature
- 3.5 Relative Light Current vs. Angular Displacement
- 4. Mechanical and Packaging Information
- 4.1 Package Dimensions
- 4.2 Polarity Identification
- 5. Soldering and Assembly Guidelines
- 6. Packaging and Ordering Information
- 6.1 Packing Specification
- 6.2 Label Specification
- 7. Application Suggestions
- 7.1 Typical Application Scenarios
- 7.2 Design Considerations
- 8. Technical Comparison and Differentiation
- 9. Frequently Asked Questions (Based on Technical Parameters)
- 10. Practical Use Case Example
- 11. Operating Principle Introduction
- 12. Industry Trends and Context
- 13. Disclaimer and Usage Notes
1. Product Overview
The PD333-3C/H0/L811 is a high-speed, high-sensitivity silicon PIN photodiode encapsulated in a standard 5mm diameter plastic package. The device utilizes a water-clear epoxy lens, making it sensitive to a broad spectrum of radiation, including both visible light and infrared wavelengths. Its primary design focus is on achieving fast response times and high photo sensitivity while maintaining a small junction capacitance, making it suitable for applications requiring precise and rapid light detection.
Key advantages of this component include its compliance with modern environmental and safety standards. It is a Pb-Free (Lead-Free) product, compliant with the EU REACH regulation, and adheres to halogen-free requirements, with Bromine (Br) and Chlorine (Cl) content each below 900 ppm and their sum below 1500 ppm. The product itself is designed to remain within RoHS compliant specifications.
2. Technical Specifications Deep Dive
2.1 Absolute Maximum Ratings
The device is designed to operate reliably within specified limits. Exceeding these ratings may cause permanent damage.
- Reverse Voltage (VR): 35 V - The maximum reverse bias voltage that can be applied across the photodiode.
- Power Dissipation (Pd): 150 mW - The maximum power the device can dissipate.
- Operating Temperature (Topr): -25°C to +85°C - The ambient temperature range for normal operation.
- Storage Temperature (Tstg): -40°C to +100°C - The temperature range for non-operational storage.
- Lead Soldering Temperature (Tsol): 260°C for a maximum of 5 seconds.
2.2 Electro-Optical Characteristics (Ta=25°C)
These parameters define the core performance of the photodiode under typical conditions.
- Spectral Bandwidth (λ0.1): 400 nm to 1100 nm. The device responds to light from the violet/blue region well into the near-infrared.
- Peak Sensitivity Wavelength (λP): 940 nm (Typical). The photodiode is most sensitive in the near-infrared spectrum.
- Open-Circuit Voltage (VOC): 0.38 V (Typical) under an irradiance of 1 mW/cm² at 470 nm.
- Short-Circuit Current (ISC): 45 μA (Typical) under an irradiance of 1 mW/cm² at 470 nm.
- Reverse Light Current (IL): This is the photocurrent generated when the diode is reverse-biased.
- 46 μA (Typical) at 470 nm, VR=5V, Ee=1 mW/cm².
- 60 μA (Typical) at 940 nm (peak sensitivity), VR=5V, Ee=1 mW/cm².
- Reverse Dark Current (ID): 10 nA (Maximum) at VR=10V in complete darkness. This is the leakage current and is a key parameter for low-light sensitivity.
- Reverse Breakdown Voltage (VBR): 130 V (Typical), with a minimum of 35 V, measured at a reverse current of 100 μA in darkness.
- View Angle (2θ1/2): 80° (Typical). This defines the angular range over which the photodiode maintains half of its on-axis sensitivity.
3. Performance Curve Analysis
The datasheet includes several characteristic curves essential for design engineers.
3.1 Power Dissipation vs. Ambient Temperature
A graph shows the derating of the maximum allowable power dissipation as the ambient temperature increases. The rated 150 mW is valid at 25°C, and it decreases linearly to 0 mW at 100°C. This curve is critical for ensuring the device does not overheat in the application environment.
3.2 Spectral Sensitivity
This curve illustrates the relative responsivity of the photodiode across its operational wavelength range (400-1100 nm), confirming the peak sensitivity around 940 nm and significant response in the visible spectrum due to the water-clear lens.
3.3 Reverse Light Current vs. Irradiance
This graph demonstrates the linear relationship between the generated photocurrent (IL) and the incident light power density (Ee). It confirms the device's suitability for light measurement applications where linearity is important.
3.4 Dark Current vs. Ambient Temperature
The dark current (ID) increases exponentially with temperature. This curve is vital for applications operating at elevated temperatures, as it defines the noise floor of the detector.
3.5 Relative Light Current vs. Angular Displacement
This polar plot visually represents the 80° view angle, showing how the detected signal strength falls off as the angle of incident light moves away from the central axis (0°).
4. Mechanical and Packaging Information
4.1 Package Dimensions
The photodiode comes in a standard 5mm radial leaded package. Key dimensions include a body diameter of 5.0mm, a typical epoxy dome height, and lead spacing. All unspecified tolerances are ±0.25mm. A detailed dimensional drawing is provided in the datasheet for PCB footprint design.
4.2 Polarity Identification
The cathode (K) is typically identified by a longer lead, a flat spot on the package rim, or other marking as per the package drawing. Correct polarity must be observed during circuit assembly for proper reverse-bias operation.
5. Soldering and Assembly Guidelines
Careful handling during soldering is crucial to prevent damage to the epoxy bulb and internal structure.
- General Rule: Maintain a minimum distance of 3mm from the solder joint to the epoxy bulb. Solder beyond the base of the tie bar is recommended.
- Hand Soldering: Use an iron with a tip temperature not exceeding 350°C (30W max). Limit soldering time to 3 seconds per lead.
- Wave/DIP Soldering: Preheat to a maximum of 100°C for up to 60 seconds. The solder bath temperature should not exceed 260°C, with a dwell time of 5 seconds maximum.
- Critical Instructions:
- Avoid applying mechanical stress to the leads while the device is at high temperature.
- Do not perform dip or hand soldering more than once.
- Protect the epoxy bulb from shock or vibration until the device cools to room temperature.
- Avoid rapid cooling from peak soldering temperature.
- Always use the lowest possible soldering temperature that achieves a reliable joint.
6. Packaging and Ordering Information
6.1 Packing Specification
The devices are packed in anti-static bags for protection. The standard packing flow is:
- 500 pieces per anti-static bag.
- 5 bags (2500 pieces) per inner carton.
- 10 inner cartons (25,000 pieces) per master outside carton.
6.2 Label Specification
The product label contains key information for traceability and identification, including Customer Part Number (CPN), Product Number (P/N), Packing Quantity (QTY), Lot Number, and date codes (month identifier).
7. Application Suggestions
7.1 Typical Application Scenarios
- High-Speed Photo Detection: Suitable for data communication links (e.g., IR remote controls, optical encoders, proximity sensors) where fast pulse detection is needed.
- Security Systems: Can be used in intrusion detection beams, smoke detectors, or ambient light sensing for automatic lighting control.
- Camera Systems: Applicable for light metering, automatic exposure control, or as an IR cut filter control sensor.
7.2 Design Considerations
- Biasing: For fastest response and linearity, operate the photodiode in reverse-bias (photoconductive) mode. A transimpedance amplifier (TIA) is commonly used to convert the photocurrent into a voltage.
- Bandwidth vs. Sensitivity: The junction capacitance (implied by fast response) and load resistor value will determine the circuit's bandwidth. A trade-off exists between bandwidth (lower R) and sensitivity/output voltage (higher R).
- Optical Design: The 80° view angle is relatively wide. For directional sensing, an aperture or lens tube may be necessary to restrict the field of view.
- Dark Current Compensation: In precision low-light applications, the dark current and its variation with temperature may need to be compensated for in the signal conditioning circuitry.
8. Technical Comparison and Differentiation
Compared to standard PN photodiodes, this PIN photodiode offers distinct advantages:
- Faster Response Time: The intrinsic (I) region in a PIN structure reduces junction capacitance, enabling higher switching speeds and bandwidth.
- Improved Linearity: The wide intrinsic region allows for better linearity of photocurrent with respect to incident light power over a broad range.
- Lower Dark Current (at comparable voltages): While dependent on the specific design, the structure can sometimes allow for lower leakage currents.
- Broad Spectrum Sensitivity: The water-clear lens, unlike tinted lenses, does not filter out visible light, making it a versatile choice for applications needing response from visible to near-IR.
9. Frequently Asked Questions (Based on Technical Parameters)
Q1: What is the difference between operating at 470nm vs. 940nm?
A: The photodiode is significantly more sensitive at its peak wavelength of 940nm (60 μA typical vs. 46 μA at 470nm under the same conditions). For maximum signal output, IR sources around 940nm are ideal. The response at 470nm allows the device to be used with blue/green visible light sources as well.
Q2: Can I use this photodiode without a reverse bias voltage?
A: Yes, it can be used in photovoltaic mode (zero bias), generating the open-circuit voltage (VOC). However, for high-speed or most linear applications, reverse-biasing (photoconductive mode) is recommended as it reduces junction capacitance and improves response time.
Q3: How critical is the 3mm soldering distance rule?
A: Very critical. Excessive heat conducted up the lead can crack the epoxy seal or damage the semiconductor chip, leading to immediate failure or reduced long-term reliability.
Q4: What does the "View Angle" specification mean for my design?
A: It means the photodiode will detect light effectively within an 80° cone (40° off-axis in any direction). Light incident at angles greater than this will produce a significantly weaker signal. This is important for aligning the sensor with a light source or defining a detection zone.
10. Practical Use Case Example
Designing a Simple Proximity Sensor:
The PD333-3C/H0/L811 can be paired with an infrared LED (e.g., emitting at 940nm) to create a proximity or object detection sensor. The IR LED is driven with a pulsed current. The photodiode, placed adjacent to the LED but optically isolated, detects the IR light reflected from an object. The photodiode's output is connected to a TIA and then a comparator. When no object is present, the detected signal is low (ambient IR only). When an object comes close, the reflected pulse increases the signal above a set threshold, triggering the comparator. The fast response time of the PIN diode allows for rapid detection and can support modulated signals to reject ambient light interference.
11. Operating Principle Introduction
A PIN photodiode is a semiconductor device with a three-layer structure: P-type, Intrinsic (undoped), and N-type (P-I-N). When reverse-biased, the intrinsic region becomes fully depleted of charge carriers, creating a wide electric field region. Photons incident on the device with energy greater than the semiconductor's bandgap create electron-hole pairs. The strong electric field in the intrinsic region rapidly sweeps these carriers to their respective terminals, generating a photocurrent that is proportional to the incident light intensity. The wide intrinsic region is key: it reduces the junction capacitance (enabling high speed) and increases the volume where photons can be absorbed (improving sensitivity, especially for longer wavelengths like IR).
12. Industry Trends and Context
Silicon PIN photodiodes like the PD333-3C/H0/L811 remain fundamental components in optoelectronics. Current trends in the industry include:
- Miniaturization: While 5mm is a standard through-hole package, there is a strong drive towards surface-mount device (SMD) packages (e.g., 0805, 0603) for automated assembly and space-constrained designs.
- Integration: Increasing integration of the photodiode with on-chip amplification, filtering, and digital logic to create "smart optical sensors" that provide a processed digital output.
- Enhanced Performance: Ongoing development focuses on further reducing dark current, improving sensitivity (responsivity) at specific wavelengths, and expanding the spectral range into deeper infrared using materials like InGaAs.
- Application-Specific Optimization: Photodiodes are being tailored for emerging applications in consumer electronics (smartphone sensors, wearables), automotive (LiDAR, in-cabin sensing), and industrial automation (machine vision, spectroscopy).
13. Disclaimer and Usage Notes
Critical legal and technical disclaimers accompany this product data:
- The manufacturer reserves the right to adjust product materials.
- The product meets published specifications for 12 months from the shipment date.
- Graphs and typical values are for reference; they are not guaranteed minimum or maximum limits.
- The manufacturer assumes no responsibility for damage resulting from operation outside the Absolute Maximum Ratings or misuse.
- The datasheet content is copyrighted; reproduction requires prior consent.
- Important Safety Notice: This product is not intended for use in military, aircraft, automotive, medical, life-sustaining, life-saving, or any other safety-critical application where failure could lead to human injury or death. For such applications, explicit authorization must be obtained.
LED Specification Terminology
Complete explanation of LED technical terms
Photoelectric Performance
| Term | Unit/Representation | Simple Explanation | Why Important |
|---|---|---|---|
| Luminous Efficacy | lm/W (lumens per watt) | Light output per watt of electricity, higher means more energy efficient. | Directly determines energy efficiency grade and electricity cost. |
| Luminous Flux | lm (lumens) | Total light emitted by source, commonly called "brightness". | Determines if the light is bright enough. |
| Viewing Angle | ° (degrees), e.g., 120° | Angle where light intensity drops to half, determines beam width. | Affects illumination range and uniformity. |
| CCT (Color Temperature) | K (Kelvin), e.g., 2700K/6500K | Warmth/coolness of light, lower values yellowish/warm, higher whitish/cool. | Determines lighting atmosphere and suitable scenarios. |
| CRI / Ra | Unitless, 0–100 | Ability to render object colors accurately, Ra≥80 is good. | Affects color authenticity, used in high-demand places like malls, museums. |
| SDCM | MacAdam ellipse steps, e.g., "5-step" | Color consistency metric, smaller steps mean more consistent color. | Ensures uniform color across same batch of LEDs. |
| Dominant Wavelength | nm (nanometers), e.g., 620nm (red) | Wavelength corresponding to color of colored LEDs. | Determines hue of red, yellow, green monochrome LEDs. |
| Spectral Distribution | Wavelength vs intensity curve | Shows intensity distribution across wavelengths. | Affects color rendering and quality. |
Electrical Parameters
| Term | Symbol | Simple Explanation | Design Considerations |
|---|---|---|---|
| Forward Voltage | Vf | Minimum voltage to turn on LED, like "starting threshold". | Driver voltage must be ≥Vf, voltages add up for series LEDs. |
| Forward Current | If | Current value for normal LED operation. | Usually constant current drive, current determines brightness & lifespan. |
| Max Pulse Current | Ifp | Peak current tolerable for short periods, used for dimming or flashing. | Pulse width & duty cycle must be strictly controlled to avoid damage. |
| Reverse Voltage | Vr | Max reverse voltage LED can withstand, beyond may cause breakdown. | Circuit must prevent reverse connection or voltage spikes. |
| Thermal Resistance | Rth (°C/W) | Resistance to heat transfer from chip to solder, lower is better. | High thermal resistance requires stronger heat dissipation. |
| ESD Immunity | V (HBM), e.g., 1000V | Ability to withstand electrostatic discharge, higher means less vulnerable. | Anti-static measures needed in production, especially for sensitive LEDs. |
Thermal Management & Reliability
| Term | Key Metric | Simple Explanation | Impact |
|---|---|---|---|
| Junction Temperature | Tj (°C) | Actual operating temperature inside LED chip. | Every 10°C reduction may double lifespan; too high causes light decay, color shift. |
| Lumen Depreciation | L70 / L80 (hours) | Time for brightness to drop to 70% or 80% of initial. | Directly defines LED "service life". |
| Lumen Maintenance | % (e.g., 70%) | Percentage of brightness retained after time. | Indicates brightness retention over long-term use. |
| Color Shift | Δu′v′ or MacAdam ellipse | Degree of color change during use. | Affects color consistency in lighting scenes. |
| Thermal Aging | Material degradation | Deterioration due to long-term high temperature. | May cause brightness drop, color change, or open-circuit failure. |
Packaging & Materials
| Term | Common Types | Simple Explanation | Features & Applications |
|---|---|---|---|
| Package Type | EMC, PPA, Ceramic | Housing material protecting chip, providing optical/thermal interface. | EMC: good heat resistance, low cost; Ceramic: better heat dissipation, longer life. |
| Chip Structure | Front, Flip Chip | Chip electrode arrangement. | Flip chip: better heat dissipation, higher efficacy, for high-power. |
| Phosphor Coating | YAG, Silicate, Nitride | Covers blue chip, converts some to yellow/red, mixes to white. | Different phosphors affect efficacy, CCT, and CRI. |
| Lens/Optics | Flat, Microlens, TIR | Optical structure on surface controlling light distribution. | Determines viewing angle and light distribution curve. |
Quality Control & Binning
| Term | Binning Content | Simple Explanation | Purpose |
|---|---|---|---|
| Luminous Flux Bin | Code e.g., 2G, 2H | Grouped by brightness, each group has min/max lumen values. | Ensures uniform brightness in same batch. |
| Voltage Bin | Code e.g., 6W, 6X | Grouped by forward voltage range. | Facilitates driver matching, improves system efficiency. |
| Color Bin | 5-step MacAdam ellipse | Grouped by color coordinates, ensuring tight range. | Guarantees color consistency, avoids uneven color within fixture. |
| CCT Bin | 2700K, 3000K etc. | Grouped by CCT, each has corresponding coordinate range. | Meets different scene CCT requirements. |
Testing & Certification
| Term | Standard/Test | Simple Explanation | Significance |
|---|---|---|---|
| LM-80 | Lumen maintenance test | Long-term lighting at constant temperature, recording brightness decay. | Used to estimate LED life (with TM-21). |
| TM-21 | Life estimation standard | Estimates life under actual conditions based on LM-80 data. | Provides scientific life prediction. |
| IESNA | Illuminating Engineering Society | Covers optical, electrical, thermal test methods. | Industry-recognized test basis. |
| RoHS / REACH | Environmental certification | Ensures no harmful substances (lead, mercury). | Market access requirement internationally. |
| ENERGY STAR / DLC | Energy efficiency certification | Energy efficiency and performance certification for lighting. | Used in government procurement, subsidy programs, enhances competitiveness. |