LPS60-24

The LPS60-24 has controlled inrush current to prevent nuisance tripping of circuit breakers: Typical inrush current is 30A peak for less than 5ms at 230VAC cold start; Inrush is lower at 115VAC (approximately 20A peak); The inrush current is limited by internal NTC thermistors and soft-start circuitry; Multiple modules can typically be powered from a single circuit breaker without coordination issues. For applications with very strict inrush limits, external inrush current limiters can be added. The inrush specification assumes startup at maximum input voltage with fully discharged input capacitors. Warm start (restarting immediately after shutdown) may have lower inrush due to residual charge on capacitors.

For multiple modules on a single circuit, verify total inrush current against breaker trip curves.

The LPS60-24 requires a minimum load for proper regulation: Minimum load is 10% of rated output (250mA at 24V); Operating below minimum load may result in output voltage rise or instability; For applications with light or no-load conditions, add a load resistor or select a lower power module; The minimum load ensures the feedback loop operates in its designed range. For applications with variable loads down to zero, consider: Adding a 2.4kohm (0.25W) load resistor to maintain minimum load; Using a module designed for zero-load operation; Implementing a load switch that maintains minimum load when main load is disconnected. The datasheet specifies minimum load requirements for each output voltage variant.

For light load applications, verify minimum load requirements or add a load resistor to maintain regulation.

The LPS60-24 does not support direct parallel connection for current sharing. For higher power requirements, consider these alternatives: Use a single higher-power module from the MPS series (100W or 150W); Implement external OR-ing diodes for redundancy (not current sharing); Use multiple modules with separate loads rather than paralleled outputs. If redundancy is required for critical applications: Use two LPS60-24 modules with external Schottky OR-ing diodes; Each module operates independently with diode isolation; This provides N+1 redundancy but not increased power capacity. For new designs requiring more than 60W, I recommend selecting the appropriate single module from the MPS series rather than attempting to parallel LPS60 units.

For power requirements above 60W, select a single higher-power MPS series module rather than paralleling LPS60 units.

The LPS60-24 provides reinforced isolation between input and output: Isolation test voltage is 4000V AC for 60 seconds; Working voltage is 300V AC continuous; Reinforced insulation rating meets IEC 62368-1 requirements; Isolation resistance exceeds 100M ohms at 500V DC. The reinforced isolation provides safety protection equivalent to double insulation, making it suitable for: Equipment with accessible conductive parts; Medical equipment (when combined with appropriate creepage/clearance); Industrial controls requiring high reliability. The isolation barrier is tested 100% in production and designed for long-term reliability. For medical applications, verify that the specific model meets the required 2xMOPP (Means of Patient Protection) requirements for your application class.

For safety-critical applications, verify isolation ratings meet your specific safety standard requirements.

The LPS60-24 is rated for full 60W output from -25°C to +50°C ambient with natural convection cooling. Above 50°C, output power must be derated linearly to 50% at 70°C. The derating curve is based on the module's internal temperature rise and maximum allowable component temperatures. For example, at 60°C ambient, maximum output power is approximately 48W (80% of rated). The encapsulated package has better thermal performance than open-frame designs but still requires adequate airflow. For high-temperature applications, consider: Improving airflow around the module; Reducing load power; Selecting a higher-power module and operating at partial load; Mounting on a heatsink or metal chassis for improved heat dissipation. The module includes overtemperature protection that shuts down at approximately 105°C internal temperature.

For ambient temperatures above 50°C, calculate required derating or improve thermal management.

The LPS60-24 requires minimal external components for basic operation: Input fuse for safety protection (3-5A slow-blow recommended); Input filtering capacitors for EMI compliance (see application note); Output capacitors for load regulation (100-470uF typical). Optional external components include: Inrush current limiter for multiple modules on one circuit; TVS diode for input surge protection; Output filter for noise-sensitive loads; Thermal fuse for additional safety. The module includes internal EMI filtering, but external components are typically needed to meet full Class B requirements. P-Duke provides detailed application notes with recommended component values and PCB layout guidelines. For medical applications, additional isolation components may be required depending on the application class.

Follow P-Duke application notes for recommended external components to ensure safe and compliant operation.