5mm Photodiode PD333-3B/L2 Datasheet - 5mm Diameter - 32V Reverse Voltage - 150mW Power Dissipation - English Technical Document

1. Product Overview

The PD333-3B/L2 is a high-speed, high-sensitivity silicon PIN photodiode housed in a standard 5mm diameter plastic package. Its primary function is to convert light, particularly in the infrared spectrum, into an electrical current. The device features a black epoxy lens, which enhances its sensitivity to infrared radiation while providing a degree of ambient light filtering. This component is designed for applications requiring fast response times and reliable performance in various environmental conditions.

Core Advantages: The key strengths of this photodiode include its fast response time, high photosensitivity, and small junction capacitance. These characteristics make it suitable for detecting rapid changes in light intensity. The device is also compliant with RoHS and EU REACH regulations, indicating the use of lead-free materials and adherence to environmental safety standards.

Target Market: This photodiode is targeted at the electronics industry, specifically for use in security systems, high-speed optical communication links, camera light metering systems, and other optoelectronic applications where precise and rapid light detection is required.

2. Technical Parameter Deep Dive

2.1 Absolute Maximum Ratings

These ratings define the limits beyond which permanent damage to the device may occur. Operation under these conditions is not guaranteed.

• Reverse Voltage (VR): 32 V. This is the maximum reverse-bias voltage that can be applied across the photodiode terminals.
• Operating Temperature (Topr): -25°C to +85°C. The ambient temperature range for normal device operation.
• Storage Temperature (Tstg): -40°C to +100°C. The temperature range for non-operational storage.
• Soldering Temperature (Tsol): 260°C. The peak temperature the device can withstand during a soldering process, typically for a short duration (e.g., 10 seconds).
• Power Dissipation (Pc): 150 mW at or below 25°C free air temperature. The maximum power the device can safely dissipate.

2.2 Electro-Optical Characteristics

These parameters are measured at Ta=25°C and define the device's performance under specified test conditions.

• Spectral Bandwidth (λ0.5): 840 nm to 1100 nm. This is the wavelength range where the photodiode's responsivity is at least half of its peak value. It indicates sensitivity primarily in the near-infrared region.
• Peak Sensitivity Wavelength (λP): 940 nm (Typical). The wavelength of light at which the photodiode is most sensitive.
• Open-Circuit Voltage (VOC): 0.39 V (Typical). The voltage generated across the photodiode terminals under illumination (Ee=1mW/cm² at λp=940nm) when no external load is connected (open circuit).
• Short-Circuit Current (ISC): 35 µA (Typical). The current flowing through the photodiode under the same illumination when the terminals are shorted together.
• Reverse Light Current (IL): 35 µA (Typical, Min 25 µA). The current that flows when the photodiode is reverse-biased (VR=5V) and illuminated. This is a key parameter for photodetection circuits.
• Reverse Dark Current (ID): 5 nA (Typical, Max 30 nA). The small leakage current that flows under reverse bias (VR=10V) in complete darkness. Lower values are generally better for signal-to-noise ratio.
• Reverse Breakdown Voltage (VBR): Min 32 V, Typ 170 V. The reverse voltage at which the diode begins to conduct heavily (break down). The minimum rating aligns with the Absolute Maximum Rating.
• Total Capacitance (Ct): 18 pF (Typical). The junction capacitance at VR=5V and f=1MHz. A lower capacitance contributes to a faster response time.
• Rise Time / Fall Time (tr / tf): 45 ns (Typical). The time required for the output signal to rise from 10% to 90% (or fall from 90% to 10%) of its final value in response to a step change in light intensity, measured with VR=10V and RL=100Ω.

3. Performance Curve Analysis

The datasheet provides several characteristic curves that illustrate how key parameters vary with operating conditions. These are essential for circuit design.

3.1 Power Dissipation vs. Ambient Temperature

This curve shows the maximum allowable power dissipation decreasing as the ambient temperature increases above 25°C. Designers must derate the power handling capability in high-temperature environments to prevent thermal damage.

3.2 Spectral Sensitivity

This graph plots the normalized responsivity of the photodiode against wavelength. It visually confirms the peak sensitivity at 940 nm and the spectral bandwidth from approximately 840 nm to 1100 nm, highlighting its suitability for infrared applications.

3.3 Reverse Dark Current vs. Ambient Temperature

Dark current increases exponentially with temperature. This curve is critical for applications operating at elevated temperatures, as increased dark current raises the noise floor of the detection system.

3.4 Reverse Light Current vs. Irradiance (Ee)

This plot demonstrates the linear relationship between the generated photocurrent (IL) and the incident light power density (irradiance) over a specified range. It confirms the device's linear photoresponse, which is vital for accurate light measurement.

3.5 Terminal Capacitance vs. Reverse Voltage

The junction capacitance (Ct) decreases as the reverse bias voltage (VR) increases. This curve allows designers to select an operating bias voltage that optimizes the trade-off between response speed (lower capacitance at higher VR) and power consumption/noise.

3.6 Response Time vs. Load Resistance

This graph shows how the rise/fall time (tr/tf) varies with the load resistance (RL) in the detection circuit. Faster response times are achieved with smaller load resistors, but this also reduces the output voltage swing. The curve helps in selecting RL for a desired bandwidth.

4. Mechanical and Packaging Information

4.1 Package Dimension

The device is in a radial-leaded, 5mm diameter plastic package. The dimensional drawing specifies the body diameter, lead spacing, lead diameter, and overall dimensions. A note indicates standard tolerances of ±0.25mm unless otherwise specified on the drawing. The cathode is typically identified by a longer lead or a flat spot on the package rim.

4.2 Polarity Identification

The anode is connected to the shorter lead, while the cathode is connected to the longer lead. The package may also have a flat side near the cathode lead. Correct polarity must be observed during circuit assembly.

5. Soldering and Assembly Guidelines

The Absolute Maximum Rating for soldering temperature is 260°C. This is compatible with standard lead-free reflow soldering profiles (e.g., IPC/JEDEC J-STD-020). The device should not be exposed to this temperature for an extended period; typical reflow peak temperature duration is 20-40 seconds. Hand soldering with a temperature-controlled iron is also acceptable, provided the 260°C limit at the lead is not exceeded. Storage should be in a dry, ambient environment within the specified Tstg range of -40°C to +100°C to prevent moisture absorption and other degradation.

6. Packaging and Ordering Information

The standard packing specification is 200-500 pieces per bag, 5 bags per box, and 10 boxes per carton. The label on the packaging includes fields for Customer Product Number (CPN), Product Number (P/N), Packing Quantity (QTY), and Lot Number (LOT No). Other fields like CAT (Luminous Intensity Rank), HUE (Dominant Wavelength Rank), and REF (Forward Voltage Rank) are listed but are more typical for LEDs; for this photodiode, they may not be actively used for binning. The product number PD333-3B/L2 follows the manufacturer's internal naming convention.

7. Application Suggestions

7.1 Typical Application Scenarios

• High-Speed Photo Detection: Used in optical data links, barcode scanners, and laser rangefinders where the 45ns response time is advantageous.
• Security Systems: Integrated into passive infrared (PIR) motion sensors, beam break sensors, and light curtains.
• Camera Systems: Employed for automatic exposure control, flash monitoring, and infrared filtering detection.
• Industrial Sensing: Object detection, edge sensing, and opacity measurement in automated equipment.

7.2 Design Considerations

• Bias Circuit: For fastest response, operate the photodiode in reverse-bias (photoconductive) mode. A transimpedance amplifier (TIA) is commonly used to convert the photocurrent into a voltage signal.
• Noise Reduction: Shield the device and circuit from electrical noise. Use a low-noise op-amp for the TIA and consider filtering to mitigate the effects of dark current, especially at high temperatures.
• Optical Considerations: The black epoxy transmits infrared. For specific wavelength filtering, an additional external optical filter may be required. Ensure the optical aperture is clean and properly aligned.
• Load Resistor Selection: Choose RL based on the required bandwidth (see Response Time vs. Load Resistance curve) and the desired output voltage level (Vout = IL * RL).

8. Technical Comparison

Compared to standard photodiodes or phototransistors, the PD333-3B/L2 offers a balanced combination of speed and sensitivity. Its PIN structure provides a wider depletion region than a standard PN photodiode, resulting in lower junction capacitance (18 pF typical) for faster response and higher quantum efficiency in the infrared spectrum. The 5mm package offers a larger active area than smaller SMD photodiodes, collecting more light for higher signal output, which can be beneficial in low-light or longer-range detection scenarios.

9. Frequently Asked Questions (Based on Technical Parameters)

Q: What is the difference between short-circuit current (ISC) and reverse light current (IL)?
A: ISC is measured with zero bias voltage (terminals shorted), while IL is measured under an applied reverse bias (e.g., 5V). IL is typically very close to ISC for a PIN photodiode and is the parameter used in most biased detection circuits.

Q: Can I use this photodiode to detect visible light?
A: While it has some sensitivity in the visible red spectrum (near 700nm), its peak is at 940nm (infrared). For optimal performance with visible light, a photodiode with a peak sensitivity in the visible range (e.g., 550-650nm) would be more suitable.

Q: How do I convert the photocurrent (IL) into a usable voltage?
A> The most common method is using a transimpedance amplifier (TIA). The output voltage is Vout = -IL * Rf, where Rf is the feedback resistor of the TIA. This configuration also keeps the photodiode in a virtual short-circuit condition, minimizing the effects of junction capacitance.

Q: What does the "Pb free" and "RoHS compliant" designation mean?
A> It indicates that the product is manufactured without the use of lead (Pb) and complies with the European Union's Restriction of Hazardous Substances directive, which restricts specific hazardous materials in electrical and electronic equipment.

10. Practical Use Case

Designing an Infrared Proximity Sensor: The PD333-3B/L2 can be paired with an 940nm infrared LED to create a simple proximity or object detection sensor. The LED is pulsed at a specific frequency. The photodiode detects the reflected IR light. A circuit featuring the photodiode in reverse-bias mode, followed by a TIA and a band-pass filter tuned to the LED's pulse frequency, can effectively extract the weak reflected signal from ambient light noise. The 45ns response time allows for high-frequency modulation, improving noise immunity and enabling faster detection cycles.

11. Operating Principle

A PIN photodiode is a semiconductor device with an intrinsic (I) region sandwiched between P-type and N-type regions. When photons with energy greater than the semiconductor's bandgap strike the device, they generate electron-hole pairs in the intrinsic region. Under reverse bias, the electric field across the intrinsic region sweeps these charge carriers towards the respective terminals, generating a photocurrent that is proportional to the incident light intensity. The wide intrinsic region reduces junction capacitance (enabling faster response) and increases the volume for photon absorption (improving sensitivity), especially for longer wavelengths like infrared.

12. Industry Trends

The demand for photodiodes continues to grow in areas like industrial automation, automotive LiDAR, consumer electronics (e.g., smartphone proximity sensors), and biomedical sensing. Trends include further miniaturization into chip-scale packages (CSP), integration with on-chip amplification and signal processing circuitry, and the development of photodiodes for specific wavelength bands (e.g., for gas sensing). There is also a focus on improving performance metrics such as lower dark current, higher speed, and enhanced reliability under harsh environmental conditions. The PD333-3B/L2 represents a mature, reliable component in this evolving landscape, well-suited for cost-sensitive, high-volume applications requiring robust infrared detection.