Bulk capacitance for low-voltage rails
The TPSE687M006R0045: Surface-mount assembly with tape-and-reel packaging — the reel is 13-inch, 500-piece quantity typical for this case size, though the exact reel count should be confirmed at order.
ESR and ripple current handling
45 mOhm ESR at 100 kHz is the specified maximum — this sets the ripple current capability. For a 680 µF cap on a 6.3 V rail, the ripple current rating (not directly listed but derivable from ESR and dissipation factor) typically allows several hundred mA RMS before the internal temperature rise hits the 125 °C limit. ±20% tolerance on 680 µF means the actual capacitance at 25 °C can range from 544 µF to 816 µF. In a hold-up circuit, the minimum capacitance determines the droop time; in a filter, the maximum affects the corner frequency. The 6.3 V rating leaves a 1.0 V margin on a 5.0 V rail — standard practice for tantalum, which is sensitive to voltage derating for reliability.
The TPS series is a general-purpose molded tantalum line with no known second-source or pin-compatible alternative from other manufacturers — the footprint and size code E are standard, but the ESR and voltage rating are specific to this order code. Cross-reference to a different manufacturer would require a full parametric match on capacitance, voltage, ESR, and case size.