RFMW Expert Product Pick: Knowles Type MLPS/MLPSR Aluminum Electrolytic

What made you select the Knowles MLPS/MLPSR Aluminum Electrolytic as a featured product?

I chose the Knowles Type MLPS/MLPSR Aluminum Electrolytic because it delivers true high-capacitance energy storage in a low-profile package without compromising life or reliability at +105°C. In a lot of power architectures, that combination is hard to find. These capacitors are designed for ruggedized, commercial, and military-grade power supplies where volumetric efficiency, thermal stress, and vibration all collide. Whether you are stabilizing a high-current DC bus, supporting hold-up time in an AC-DC front end, or filtering ripple in a high-density DC-DC converter, the challenge is the same: you need bulk capacitance that survives elevated temperature, ripple stress, and mechanical shock over long mission profiles. Conventional electrolytics often become the weak link due to dry-out or limited life at temperature. The MLPS Flatpack addresses those constraints directly.

Technically, the MLPS/MLPSR series offers capacitance values from 120 µF to 51,000 µF across a rated voltage range of 7.5 Vdc to 450 Vdc, giving designers flexibility from low-voltage POL rails to high-voltage bus applications. These devices are fully life tested to 10,000 hours at +105°C at rated voltage and ripple current, which is a meaningful data point when calculating system MTBF. Leakage current is specified at ≤0.002CV µA after five minutes at rated voltage, supporting predictable startup behavior and controlled bias conditions in tightly regulated systems. Capacitance tolerance is ±20 percent, consistent with aluminum electrolytic technology, but backed by robust screening and process control.

Mechanically and environmentally, this series stands apart. The welded seal construction resists electrolyte dry-out, a common failure mode in conventional electrolytics operating near their thermal limits. With an operating temperature range of -55°C to +105°C and nonoperating range down to -65°C, the MLPS maintains excellent capacitance retention even at -55°C. For high-vibration environments, the optional high-vibration configuration supports up to 20 g, making it well suited for aerospace and defense platforms, mobile ground systems, and industrial environments with sustained mechanical stress. A 48-hour burn-in at rated voltage and +105°C is also available for high-reliability programs that demand additional screening before deployment.

From a system-level perspective, the low-profile Flatpack form factor simplifies mechanical integration in space-constrained enclosures. When board height is limited but energy storage requirements are not negotiable, this geometry enables higher capacitance density per unit height compared with many traditional can-style electrolytics. For power management engineers balancing thermal design, mechanical constraints, and long-life reliability modeling, that trade-off is often the deciding factor.

What are the key features/specifications of the Knowles MLPS/MLPSR Aluminum Electrolytic?

Key Features

• +105°C rated Flatpack aluminum electrolytic construction
• Life tested to 10,000 hours at +105°C, rated Vdc, and ripple current
• Capacitance range from 120 µF to 51,000 µF
• Rated voltage range from 7.5 Vdc to 450 Vdc
• Operating temperature range from -55°C to +105°C
• Welded seal to mitigate electrolyte dry-out
• High-vibration option up to 20 g
• Optional 48-hour burn-in at rated voltage and +105°C
• Leakage current ≤0.002CV µA after 5 minutes at rated voltage

What are some common markets/applications of the Knowles Type MLPS/MLPSR Aluminum Electrolytic?

Target Markets & Applications

• Ruggedized AC-DC and DC-DC power supplies
• Military and aerospace power distribution systems
• High-reliability industrial power systems
• Bulk energy storage and DC bus stabilization
• Hold-up and ride-through circuits in mission-critical systems