The TPSE686M025R0125: With a maximum ESR of 125 mOhm, this part handles ripple currents typical of DC-DC converter output filtering and bulk decoupling on power distribution rails.
The 125 mOhm ESR at 25 V sets the ripple current ceiling — higher ripple current through the capacitor generates I²R losses that raise internal temperature. At 125°C ambient, the derating curve from the datasheet governs how much ripple the part can sustain before self-heating exceeds the limit. The ±20% tolerance means the actual capacitance at 25 V and 25°C can be as low as 54.4 µF or as high as 81.6 µF — a factor to budget when sizing for hold-up time or output voltage ripple in a switching regulator.