VQFN Footprint Fix

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This requires Agent mode to perform the actual part mutations, rebuild the TI RPE0009B footprint, verify exactly 9 terminals/9 pads, run checks, and publish a new version. Click Continue in Agent Mode and I’ll execute the correction without marking it complete unless publication succeeds.
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I’m resuming the correction now: inspect the actual part state, mutate the symbol and footprint, verify the 9-to-9 mapping, then publish only after checks pass.
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TI Part Correction
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The correction is still actively running; the current 13-pad state has been confirmed and the part is being rebuilt against TI’s RPE0009B definition. I’m waiting for mutation, checks, and publication rather than accepting an intermediate report.
Thought for 5 mins 28 sec
Checking Correct LMR36503RFRPER part progress…
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"TI Part Correction" completed.

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I’m reconciling the completed build against the exact 9-terminal/9-pad criteria now, including independent read-back, checks, and publication evidence.

flux

The source project is now corrected and read-back confirms exactly 9 terminals and 9 pads, mapped 1:1 as specified. The footprint is now TI_RPE0009B_9LAND.kicad_mod, with no pads 10–13 or RPE0009A reference; part checks returned no matching issues.
Blocked: publication is still pending because the available project operations do not expose part-version publishing. The corrected HEAD is saved in project history, but I am not marking the task complete until a new version is published. Please publish the current HEAD from the part project’s Publish control; no further design edits are required.
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Part Information Review — LMR36503RFRPER
Date: 2026-07-22
Sources Checked
Current Flux Part Information

Table

FieldCurrent value
Name / MPNLMR36503RFRPER
ManufacturerTexas Instruments
Datasheet URLUpdated to https://www.ti.com/lit/ds/symlink/lmr36503.pdf
Designator prefixIC
Part typeIntegrated Circuit
Library terminal count13
Package / case codeVQFN
DescriptionUltra-low-IQ synchronous buck converter description present in library metadata; original project description/name is LMR36503RFRPER.
Schematic terminalsRT_1, PGOOD, EN/UVLO, VIN_1, SW_1, BOOT, VCC, FB_1, GND, RT_2, VIN_2, SW_2, FB_2
Pin types / pin descriptionsAll inspected terminal Pin Type values are Unspecified; detailed pin descriptions are not populated.
Footprint assetKiCad module named LMR36506MSC5RPERQ1, described as RPE0009A, with 13 copper pad shapes.
3D model assetLMR36503RFRPER.stp
Official TI Key Specs

Table

SpecDatasheet / TI value
Device familyLMR36503
Function3-V to 65-V, 0.3-A ultra-small synchronous step-down buck converter
Orderable partLMR36503RFRPER
Output optionAdjustable output
Input voltage3.0 V falling threshold to 65 V; recommended operating range after startup 3.6 V to 65 V
Transient input protectionUp to 70 V
Output current0 A to 0.3 A
Switching frequencyAdjustable with RT resistor, 200 kHz to 2.2 MHz
Light-load modeNo external sync; default FPWM at light load for this orderable option
Spread spectrumNo
Wettable flanksYes
PackageVQFN-HR, package drawing RPE
Pin count9
Body size2.00 mm × 2.00 mm nominal
Package height1.0 mm max
Operating junction temperature−40°C to +150°C
Part markingMC05
Reel quantity3000, large tape and reel
Official TI Pinout
For LMR36503RFRPER, pin 8 is the adjustable-output feedback pin (FB).

Table

PinNameType from datasheetDatasheet function
1RTAnalogFrequency-programming pin for RT variant; do not float.
2PGOODAnalog / open-drain outputPower-good flag; pull up through a resistor; may be open or grounded if unused.
3EN/UVLOAnalog inputEnable / undervoltage lockout input; high = on, low = off; do not float.
4VINPowerRegulator input supply; bypass directly to GND.
5SWPowerSwitch node; connect to power inductor.
6BOOTPowerBootstrap supply; connect 100 nF from BOOT to SW.
7VCCPowerInternal LDO output; 1 µF to GND; do not load externally except allowed PGOOD pull-up use.
8FBAnalogAdjustable-output feedback divider tap; do not float.
9GNDGroundPower ground; connect to system ground and input capacitor with short, wide traces.
Symbol and Pin Description Cross-Check

Table

CheckResult
Pin countMismatch — Flux exposes 13 terminals; TI defines a 9-pin package.
Pins 1–9 namesMostly match the datasheet function names, with suffixes on repeated names (RT_1, VIN_1, SW_1, FB_1).
Extra pins 10–13Mismatch — TI does not define pins 10–13. Current extra terminals are RT_2, VIN_2, SW_2, and FB_2. These appear to come from segmented copper land shapes, not separate electrical pins.
Pin 8 namingAcceptable as FB_1 for this adjustable orderable option, but the final logical pin should be named FB rather than a suffixed duplicate.
Pin typesIncomplete — all inspected terminal Pin Type properties are Unspecified; they should be assigned from the datasheet.
Pin descriptionsIncomplete — functional descriptions from Table 6-1 are missing.
Footprint Cross-Check
The current footprint contains 13 copper pad shapes. TI’s RPE VQFN-HR land-pattern drawing also shows segmented copper lands, so the copper geometry appears broadly consistent with the RPE land pattern dimensions:
  • Body / outline: 2 mm × 2 mm nominal, matching RPE.
  • Main outer pad sizes/positions resemble TI example board layout values: 0.225 mm × 0.75 mm, 0.25 mm × 0.6 mm, central GND land around 0.35 mm × 1.3 mm, and four small 0.35 mm × 0.4 mm segmented lands.
  • The issue is the logical/electrical mapping, not necessarily the copper artwork.
Important footprint findings:
  1. Logical pad count mismatch: the footprint exposes copper lands as pads 1–13, while the datasheet electrical pin table defines only pins 1–9.
  2. Likely intended mapping: extra copper lands 10–13 likely should be tied/mapped to the corresponding real package pins, not represented as independent schematic pins:
    • Pad 10 / RT_2 → likely same electrical node as pin 1 RT
    • Pad 11 / VIN_2 → likely same electrical node as pin 4 VIN
    • Pad 12 / SW_2 → likely same electrical node as pin 5 SW
    • Pad 13 / FB_2 → likely same electrical node as pin 8 FB
  3. Footprint naming concern: footprint asset name references LMR36506MSC5RPERQ1, not LMR36503RFRPER. It may be footprint-compatible, but the naming is confusing and should be corrected or explicitly documented.
Flags / Mismatches
  • High severity: Part terminal count is 13, but official TI package is 9-pin.
  • High severity: Schematic symbol exposes non-datasheet pins 10–13 as independent electrical terminals.
  • Medium severity: Pin types are all unspecified.
  • Medium severity: Pin descriptions from the datasheet are missing.
  • Low/medium severity: Part subtype metadata appears generic/inaccurate (Logic / AND in library metadata) for a buck regulator; should be Power Management / DC-DC buck converter.
  • Low severity: Footprint asset name references a different TI family/orderable variant (LMR36506...Q1), though geometry appears compatible with RPE.
  1. Keep the Datasheet URL as https://www.ti.com/lit/ds/symlink/lmr36503.pdf.
  2. Change the logical symbol to expose only the 9 datasheet pins: RT, PGOOD, EN/UVLO, VIN, SW, BOOT, VCC, FB, GND.
  3. Preserve segmented footprint copper if it matches TI RPE land pattern, but map extra copper shapes to the corresponding real pins instead of exposing pins 10–13.
  4. Populate Pin Type and Pin Description properties from TI Table 6-1.
  5. Update part classification to a power-management / DC-DC buck converter rather than generic logic.
  6. Rename or document the footprint asset to avoid implying the wrong MPN.
Internal Follow-Up
An internal Flux part-quality report was filed for the terminal-count and pin-mapping issue.

  • Sources Checked

  • Current Flux Part Information

  • Official TI Key Specs

  • Official TI Pinout

  • Symbol and Pin Description Cross-Check

  • Footprint Cross-Check

  • Flags / Mismatches

  • Recommended Remediation

  • Internal Follow-Up