DC-DC Power Module Selection Guide
This technical reference document provides detailed information about aipu product specifications, characteristics, and performance parameters. Use this information to support your design and analysis activities.
Electrical characteristics are specified over the operating temperature range unless otherwise noted. Parameters are guaranteed by design, testing, or statistical analysis. Typical values is the most likely parametric norm at 25°C.
Thermal characteristics require careful attention during system design. The junction-to-ambient thermal resistance depends on the mounting configuration, PCB copper area, and airflow conditions. Use thermal simulation tools to predict operating temperatures under actual conditions.
Reliability data is based on accelerated life testing and field failure analysis. Mean time between failures (MTBF) calculations follow industry-standard methodologies. Contact BeiLuo for detailed reliability reports and qualification data.
💡 FAE Insights
⚠️ Common Pitfalls
- ✗ Selecting power level without margin
- ✗ Using fixed input for battery applications
- ✗ Ignoring temperature derating requirements
- ✗ Choosing wrong package for environment
📋 Customer Cases
Industrial Automation Corp
Industrial
Challenge
Frequent module failures due to insufficient power margin and high temperature
Solution
Recalculated power requirements with proper margin, upgraded to higher power module with better thermal rating
Customer Feedback
"System reliability improved significantly, no failures in 2 years of operation"
Frequently Asked Questions
1. When should I choose fixed input vs wide input DC-DC modules?
Choose fixed input (A series) when: Input voltage is stable (such as regulated 5V, 12V, or 24V); Maximum efficiency is required; Cost is a primary concern; Space is limited. Choose wide input (B series) when: Powering from batteries with voltage variation; Input voltage fluctuates significantly; System needs to work with multiple input voltages; Flexibility is more important than maximum efficiency. Fixed input modules typically have 2-3% higher efficiency and 10-15% lower cost than equivalent wide input modules.
2. How do I calculate the required power level?
Calculate required power level: 1) Sum power consumption of all devices powered by the module (P = V × I for each device); 2) Add 20-30% margin: P_module = P_total × 1.2 to 1.3; 3) Consider startup current: Some devices draw 2-3× normal current at startup; 4) Account for temperature: At high ambient temperatures (>50°C), derate by 20-30%; 5) Select next standard power level above calculated value. Example: For devices totaling 1.5W, with 30% margin = 1.95W, select 2W or 3W module. It's better to have excess capacity than to operate at maximum rating continuously.
3. What isolation voltage do I need for my application?
Select isolation voltage based on application requirements: 1) 1000VDC: Suitable for general industrial control with low isolation requirements; 2) 1500VDC: Standard industrial grade, suitable for most industrial control, instrumentation, and communication equipment; 3) 2500VDC: High isolation grade for power systems, medical equipment, and high-voltage equipment; 4) 3000VDC: Medical grade for equipment with direct patient contact. Higher isolation voltage provides better safety margin and noise immunity but at higher cost. For most industrial applications, 1500VDC is sufficient. For medical or high-voltage applications, 2500VDC or 3000VDC is required.
4. SIP vs DIP package - which should I choose?
Choose SIP (Single In-line Package) when: Space is limited and compact design is required; Cost is a primary concern; Application environment is clean and stable; PCB density is high. Choose DIP (Dual In-line Package) when: Mechanical stability is important; Application has vibration or shock; Better heat dissipation is needed; Long-term reliability is critical. SIP packages are smaller (typically 11.5mm wide) and lower cost. DIP packages are larger (typically 19-22mm wide) but provide better mechanical strength and thermal performance. For most industrial applications, DIP is recommended for better reliability.
5. How does temperature affect power module performance?
Temperature affects power module performance in several ways: 1) Efficiency decreases at high temperatures due to increased semiconductor losses; 2) Maximum output power must be derated above 50°C ambient to prevent overheating; 3) Lifetime decreases with higher operating temperatures - every 10°C increase halves the lifetime; 4) Input voltage range may narrow at temperature extremes. Typical derating: 100% load at 25°C, 80% load at 50°C, 60% load at 70°C. Always ensure adequate ventilation and consider heat sinking for high-power or high-temperature applications. The module's internal overtemperature protection will shut down the output if temperature exceeds safe limits.