When designing USB power supplies and power delivery solutions for electronic systems and subsystems, including ICs, application-specific ICs (ASICs), central processing units (CPUs), and field-programmable gate arrays (FPGAs), designers are constantly looking for ways to Increase efficiency while ensuring stable, noise-free power over a wide temperature range in a compact form factor. They need to improve efficiency, stability and reliability, reduce costs, and reduce the form factor of their solutions. At the same time, they must also meet the increasing power performance requirements of the application, including smoothing the input and output currents of the power circuit, supporting peak power requirements, and suppressing voltage fluctuations.
To address these challenges, designers need capacitors with low equivalent series resistance (ESR) and low impedance at high frequencies to support ripple absorption and ensure smooth fast transient response. In addition, operational reliability and supply chain reliability are also important.
Looking at the issues and options,TMA series Conductive Polymer Aluminum Solid Electrolytic Capacitors are a good solution, offering high electrical performance and stability, low noise, good reliability, compact form factor, and reduced supply chain risk by not using conflict materials Low. They feature low ESR (typically measured in milliohms (mΩ)) and low impedance at high frequencies (up to 500 kilohertz (kHz)), and provide excellent noise rejection, ripple absorption, and power line decoupling. Additionally, there is capacitive stability at high operating frequencies and temperatures.
How are polymer aluminum capacitors made?
TMA series Conductive Polymer Aluminum Solid Electrolytic Capacitors include an etched aluminum foil anode, an aluminum oxide film dielectric, and a conductive polymer cathode (Figure 1). Depending on the specific device, capacitance ranges from 6.8 to 470 microfarads (μF) and voltage ranges from 2 to 25 volts direct current (Vdc).
Figure 1: A polymer aluminum electrolytic capacitor model showing the relationship between the etched aluminum foil anode (left), aluminum oxide film dielectric (center), and conductive polymer cathode (right).
In UF Capacitors's TMA series Conductive Polymer Aluminum Solid Electrolytic Capacitors of devices, an etched aluminum foil is applied directly to the positive electrode, while the conductive polymer is covered with carbon paste and connected to the negative electrode using conductive silver paste (Figure 2). The entire structure is clad in molded epoxy resin to provide mechanical strength and environmental protection. The result is a low-profile, halogen-free surface-mount package with a Moisture Sensitivity Level (MSL) 3. The multilayer (laminated) construction of aluminum foil and oxide film sets UF Capacitors's TMA series Conductive Polymer Aluminum Solid Electrolytic Capacitors apart from typical aluminum electrolytic capacitors, such as can-wound structures that use a polymer or electrolyte as the cathode.
Figure 2: UF Capacitors's TMA series Conductive Polymer Aluminum Solid Electrolytic Capacitors device structure showing the conductive polymer (pink), etched aluminum foil (white), aluminum (Al) oxide film (blue), and carbon paste connecting the conductive polymer to the negative electrode (brown) and silver paste (dark gray), and epoxy resin shell
The performance characteristics of polymer aluminum electrolytic capacitors make them ideal for power management applications, including power supplies for CPUs, ASICs, FPGAs, and other large ICs, and to support the peak power demands of USB power systems (Figure 3)
TMA series Conductive Polymer Aluminum Solid Electrolytic Capacitors have low ESR, low impedance, and stable capacitance, making them ideal for applications such as smoothing and eliminating ripple, especially on power lines with large fluctuations in current load. In these applications, polymer aluminum capacitors can be used in combination with MLCCs.
TMA series Conductive Polymer Aluminum Solid Electrolytic Capacitors provide power management functions, while MLCCs filter high-frequency noise from the IC's power pins. Polymer aluminum capacitors also support the peak power demands of USB power systems while maintaining a small printed circuit board footprint
UF Capacitors's TMA series Conductive Polymer Aluminum Solid Electrolytic Capacitors
TMA Series CHIP TYPE, STANDARD
Operating with wide temperature range -55~+105°C
Low ESR, high ripple current
Load life of 2000 hours
RoHS & REACH compliant, Halogen-free
Capacitance Range: 3.3 ~ 1500μF
Voltage Range: 2.5 ~ 25V
Size: 4*5.5mm; 5*6mm; 6.3*5.5mm; 8*7mm; 8*12mm;10*10mm;10*12.7mm
Summarize
For designers of power delivery systems, achieving the optimal balance of energy efficiency, performance, cost, stability, reliability, and form factor is extremely difficult, especially when powering large ICs such as MCUs, ASICs, and FPGAs. and when supporting the peak power demands of USB applications. One of the major components of the power signal chain is the capacitor, and these devices have many features that help meet the designer's requirements—if the correct technology is used.
As shown above, polymer aluminum capacitors help designers find the right balance. Their construction ensures low impedance at frequencies up to 500 kHz, low ESR, good ripple smoothing, and good noise rejection and power line decoupling. Additionally, they are not limited by DC offset and are self-healing, increasing operational reliability. The supply chain is also more reliable as conflict materials are not used. In summary, polymer aluminum capacitors provide designers with a higher performance option to address a variety of power management system requirements.