📌 Product Overview
This component is a 3-pin Through-Hole/SMT compatible Phototransistor optimized for infrared detection. It acts as an optical switch that converts infrared light signals into electrical current.
💡 Engineers typically select this for signal reception in consumer electronics and industrial counters. The primary selection variables are the spectral sensitivity (λp=880nm) and the high current transfer ratio (hFE), which determine detection range and signal clarity in ambient light environments.
🎯 Typical Applications & Design Context
- Infrared Remote Controls: High sensitivity ensures reliable signal pickup from standard IR remotes.
- Industrial Counting & Smart Meters: Fast response times (Tr/Tf ≈ 15μs) allow for accurate detection of moving objects or rotating machinery.
- Robotics & Smart Cars: Used for line following or obstacle avoidance due to the ability to detect modulated IR signals.
- Camera Monitoring: Acts as a trigger in low-light detection systems.
📊 Key Technical Specifications
| Parameter | Symbol | Value (Typ/Max) | Notes |
|---|---|---|---|
| Peak Wavelength | λp | 880 nm | Optimized for standard IR emitters |
| Spectral Bandwidth | λ0.5 | 700 - 1100 nm | Visible to near-IR range |
| Current Transfer Ratio | hFE | 200 - 2300 | High gain; improves SNR |
| Collector Dark Current | Iceo | ≤ 30 nA | Low noise floor |
| Response Time | Tr / Tf | ≤ 15 μs | Suitable for 1kHz-38kHz carrier signals |
⚠️ Absolute Maximum Ratings & Process Limits
| Parameter | Rating | Unit | E-E-A-T Validation Insight |
|---|---|---|---|
| Power Dissipation | 100 | mW | ⚠️ Thermal Runaway Risk: Exceeding this in enclosed housings (e.g., smart meter casings) without airflow will rapidly degrade the black epoxy encapsulant. |
| Collector Current | 50 | mA | Circuit Protection: Direct connection to power rails without limiting the resistor will cause immediate bond wire fusing. |
| Soldering (Reflow) | 240 | °C / 6s | SMT Defect Alert: >250°C or prolonged dwell time causes delamination between the black epoxy body and the metal leads, creating mechanical weakness. |
| ESD Tolerance | 2000 | V | Assembly Risk: Despite being a robust phototransistor, 2000V is relatively low for uncontrolled environments; grounding is mandatory during pick-and-place. |
🧩 Package, Dimensions & Assembly Notes
The component uses a compact, molded black epoxy package (approx 2.1 x 2.3 x 2.6 mm).
- PCB Footprint: Designed for standard lead spacing. Ensure the "welding point is 2.0mm above the colloid bottom" to prevent thermal stress cracking during wave soldering.
- MSL (Moisture Sensitivity):Level 2.
- 🔒 Floor Life: After opening the sealed bag, you have 168 hours (7 days) to solder components if the factory floor is ≤30°C / 60% RH. Exceeding this "floor life" without baking leads to "popcorning" cracks during reflow.
- Baking Profile: If moisture limits are exceeded, bake at (60±5)°C for 24 hours.
🔍 Procurement & Sourcing Insights
- Sensitivity Binning (PD3 vs. PD5): Datasheets often list photocurrent ranges (e.g., 300-400μA vs. 500-600μA). 🔒 Procurement Trap: Mixing these batches on the same production line can cause gain variations in the receiver circuit. Always specify the "Code" (PD3 or PD5) in the PO.
- Supply Chain Volatility: The black epoxy resin supply is subject to petrochemical market fluctuations.
- Alternative Validation: When swapping vendors for this generic part, the critical parameter to match is the λp (Peak Wavelength). A shift to 940nm will render the device "blind" to standard 880nm remote controls.
❓ FAQ
Q: What happens if I use a standard LED profile (260°C) for reflow soldering?
A: You risk thermal degradation. The datasheet explicitly caps the max temperature at 240°C for 6 seconds. Using a standard lead-free profile (peaking 250°C+) may melt the internal lens structure or cause the leads to shift, resulting in a physically misaligned sensor.
Q: Can I use this phototransistor for sunlight detection?
A: Technically, yes (λ0.5 covers visible light), but it is not recommended. The spectral response is centered at 880nm (Infrared). Sunlight contains massive amounts of IR, which will saturate the transistor (Iceo increases), potentially masking the modulated signal from a remote. An optical filter is usually required.
Q: My receiver has intermittent range issues. Is this a component defect?
A: Likely not. Check the MSL compliance. If the parts were left on the production floor for >7 days (168 hours) before soldering, internal moisture expansion may have compromised the optical alignment of the die inside the epoxy, scattering the light and reducing sensitivity.
Q: How do I verify authenticity if the brand is unknown?
A: Perform a V-I curve trace on the collector-emitter junction while illuminating the device with a known 880nm source. Compare the resulting current (IPCE) against the datasheet's "Photocurrent" table (typically 300-600μA). A deviation of >20% suggests a counterfeit or remarked component.
