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Selection Guide and Application Comparison: 1N2820B vs 1N5550

High-reliability Zener diodes play a key role in power regulation, telecom systems, and industrial control. Both 1N2820B and 1N5550 are classic Zener diodes, but they differ in voltage rating, power handling, and intended applications.

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🔍 1. Technical Comparison
Parameter 1N2820B 1N5550
Zener Voltage (Vz) 6.8V ± 5% 200V ± 10%
Max Power Dissipation 10W 5W
Operating Current Tens to hundreds of mA Few mA to tens of mA
Leakage Current (Ir) < 100μA < 20μA (@ Vr = 150V)
Package Type DO-4 (bolt-type) DO-5 (bolt-type)
Polarity Configuration Cathode to case Anode to case
Application Focus High-current clamping, power rails Precision high-voltage protection

📘 2. Typical Application Scenarios
🔹 Recommended Uses for 1N2820B:
Linear voltage regulator protection circuits

Industrial surge suppression (e.g., motor controllers)

Output voltage clamping in DC-DC converters

Battery charging constant-voltage control

🔹 Recommended Uses for 1N5550:
High-voltage signal clamping circuits

Power input protection in telecom base stations

Precision high-voltage signal regulation

Voltage regulation in UPS or PLC systems

🌡️ 3. Thermal Design & Mounting Tips
Both devices feature bolt-style packages, allowing for direct heat sink mounting.

Use thermal grease or pads to ensure proper thermal conductivity.

For continuous operation near maximum power, design with at least 50% thermal margin (e.g., operate 10W parts at 6–7W typical).

🛡️ 4. Reliability and Alternatives
Durability: Both models are rated for military/industrial use, supporting high temp/humidity/surge conditions.

Alternatives:

Need higher breakdown voltage? ➜ Consider 1N5551 (400V)

Need higher power than 1N2820B? ➜ Use 1N2837B (12V, 15W)

Base your selection on Zener voltage (Vz), power dissipation (Ptot), and target circuit conditions:

For high current clamping ➜ Choose 1N2820B

For high-voltage precision regulation ➜ Choose 1N5550

Need datasheets, footprints, or bulk quote support? Visit Xecor’s official site for the latest resources and offers.

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