Texas Instruments TPS63031DSKR: PCB footprint and gate checks

The Texas Instruments TPS63031DSKR is a fixed 3.3 V buck-boost converter from Texas Instruments. Its package or board interface is 10-pin 2.5 × 2.5 mm WSON, and its relevant electrical envelope is 1.8–5.5 V input, fixed 3.3 V output; output current depends strongly on input voltage. It communicates or connects through single-inductor four-switch buck-boost. Those fields belong together: substituting a familiar family name while changing package, voltage, sensing port, mount style, current class, or interface behavior can leave a PCB that passes ordinary net checks and still cannot be assembled or function safely.

TPS63031 maintains 3.3 V as a Li-ion source moves above and below the output, using a compact four-switch power stage.

Common uses include single-cell Li-ion 3.3 V rails and stable 3.3 V across battery discharge. Start with the manufacturer drawing and recommended application, then record the exact ordering suffix alongside the KiCad symbol and footprint. This makes the library evidence reviewable when the part is re-sourced months later.

• Follow the four-switch converter's reference layout exactly: both switch nodes, input/output capacitors, inductor, and exposed pad need short, symmetric high-current paths.
• Keep feedback and mode-control traces away from both switch nodes. Use thermal vias and copper without enlarging noisy nodes into radiating plates.

Follow TI's two-switch-node layout, keep input/output caps tight, and calculate battery-side current at low voltage rather than quoting output current alone.

• Verify operation across the full range where input may be above, below, or equal to output. Select inductor and capacitors for worst-case RMS/peak current and check mode transitions, current limit, quiescent current, and startup.
• Treat battery cutoff and load disconnect separately from regulation. Confirm enable, power-good, and output-discharge behavior for every source state including USB insertion.

Put the support components where their current, thermal, optical, RF, or measurement loops are actually short—not merely where ratsnest lines look tidy. Confirm pin one from the package view used in the datasheet, distinguish top view from mating face or bottom view, and check mask, paste, drill, courtyard, enclosure, and rework access independently. A correct copper pad pattern can still be a bad production footprint when the sensing opening, connector latch, exposed pad, thermal path, or cable volume is wrong.

MakeIRL’s release gate should not stop at “the symbol has the right number of pins.” For this part, a useful gate review combines ERC/DRC with the following package- and function-specific evidence:

1. Check both switch-node loops, inductor value/saturation, input/output capacitors, feedback, mode pins, enable, power-good, current limit, and exposed-pad ground.
2. Check reverse current and power-path behavior when input crosses output or another supply is present, plus thermal and battery-current limits.
3. Check the exact package and ordering suffix because pin-compatible-looking buck-boost families can use different mode defaults or current limits.
4. For Texas Instruments TPS63031DSKR, check DSK pad, fixed 3.3 option, inductor peak current, both switch nodes, PS/SYNC, EN, capacitors, low-input output current, and reverse path.

Then run ERC and DRC, refill zones, and inspect the fabrication and assembly outputs. Cross-probe the exact pads named by any finding, compare the BOM MPN with the footprint and electrical limits above, and verify that a real cable, enclosure, antenna, sensor stimulus, load, or thermal path can be tested on the assembled unit. An exclusion is evidence that someone dismissed a marker; it is not evidence that the underlying condition was resolved.

The most expensive errors are usually plausible: a footprint from a sibling package, a breakout-board voltage copied to the bare IC, a headline current used without thermal analysis, or a connector family selected by pitch alone. For Texas Instruments TPS63031DSKR, review these failure modes explicitly:

• Assuming the same 800 mA is available at 1.8 V input and 3.3 V output violates power balance and switch-current limits.
• Validating only at nominal battery voltage and missing instability, dropout, or current limit as the cell crosses the regulated output.
• Connecting USB and battery rails without checking reverse-current blocking through the converter.

Sourcing note. Specify TPS63031DSKR exactly; adjustable TPS63030 and related options use different feedback/control BOMs. The approved vendor list should preserve manufacturer, full suffix, package, voltage/range/accuracy grade, lifecycle, and mating or external components. An alternate is real only after its datasheet, land pattern, electrical behavior, firmware assumptions, and assembly process have all been compared—not because a distributor search places it in the same parametric row.