Part Review and Datasheet Update
Thought for 1 min 31 sec
The part project has no Datasheet URL set, and the official Semtech product page doesn’t expose a public datasheet PDF in the accessible page content. I’m checking alternate official/resource pages and distributor references before deciding whether to flag it as unavailable rather than setting a non-datasheet link.
Worked for 1 min 34 sec
Completed the LR2021IMLTRT part review and saved the detailed findings in LR2021IMLTRT Part Review.
Open items:
- No public official Semtech LR2021 datasheet PDF was found, so I did not set the Datasheet URL to a non-datasheet page.
- Pin-by-pin verification is blocked until the official Semtech datasheet/package drawing is available.
- Main flagged issue: exposed pad is represented as
GNDpin0; plausible for 32-VFQFN EP, but it should be confirmed and possibly renamedEP/GND.
Suggested next steps:
- Upload or provide Semtech’s official LR2021 datasheet if you have access.
- Confirm whether exposed pad numbering should be
0,33, orEP. - I can then update the Datasheet URL and correct any symbol/footprint mismatches.
Use uploaded datasheet
Fix exposed pad
Search gated docs
Run ERC DRC
Improve pin descriptions
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LR2021IMLTRT Part Review
Scope
Reviewed available part information for the Flux part project
LR2021IMLTRT, including project metadata, symbol terminals, PCB footprint pads, and public web sources for official Semtech documentation.Available part information
Table
| Field | Observed value |
|---|---|
| MPN | LR2021IMLTRT |
| Manufacturer | Semtech / Semtech Corporation |
| Description | LR2021 LoRa Plus fourth-generation LoRa IP, long-range low-power multi-band LoRa transceiver |
| Distributor/package evidence | 32-VFQFN exposed pad / 32-VFQFN EP |
| Flux project pad count | 33 pads |
| Symbol terminal count | 33 terminals |
| Datasheet URL property | Not set / unavailable through datasheet query |
Datasheet search result
No public official Semtech datasheet PDF URL was found in the accessible Semtech LR2021 product page or public web search results. The official Semtech product page is:
Because this is not a datasheet PDF and no official datasheet URL was exposed, I did not set the Datasheet property to a non-datasheet link. A third-party module datasheet exists for LPRS eRIC-LR2021, but it is for a module using the LR2021, not the Semtech IC itself, so it is not valid for symbol/footprint verification.
Public key specs from Semtech product page
- LoRa Plus LR2021, fourth-generation LoRa IP transceiver
- Supports terrestrial and NTN/SATCOM use cases
- Bands: sub-GHz, 2.4 GHz ISM, and licensed S-band
- Backward-compatible with prior LoRa devices for LoRaWAN compatibility
- Modulations/PHYs: LoRa, FLRC, FSK, OOK, O-QPSK, LR-FHSS
- FLRC data rate up to 2.6 Mbps
- LoRa data rate up to 125 kbps
- TX output range: +22 dBm to -10 dBm
- LoRa sensitivity down to approximately -141.5 dBm at SF12 / 125 kHz
Symbol terminals observed
The symbol contains these pin-number/name mappings:
Table
| Pin | Symbol terminal | Pin type in Flux |
|---|---|---|
| 1 | VR_PA | Power In |
| 2 | VPAX2 | Power In |
| 3 | NTC | Passive |
| 4 | XTA | Input |
| 5 | XTB | Input |
| 6 | VTCXO/VNTC | Power In |
| 7 | DIO11 | Bi-Directional |
| 8 | DIO10 | Bi-Directional |
| 9 | DIO9 | Bi-Directional |
| 10 | DIO8 | Bi-Directional |
| 11 | DIO7 | Bi-Directional |
| 12 | VDCC1 | Power In |
| 13 | VPAX1 | Power In |
| 14 | LXB | Passive |
| 15 | GND_DCC | Power In |
| 16 | LXA | Passive |
| 17 | VBAT | Power In |
| 18 | DIO6 | Bi-Directional |
| 19 | DIO5 | Bi-Directional |
| 20 | ~{RESET} | Input |
| 21 | MISO | Output |
| 22 | MOSI | Input |
| 23 | SCK | Input |
| 24 | NSS | Input |
| 25 | BUSY | Output |
| 26 | VDCC2 | Power In |
| 27 | RFO_LF2 | Output |
| 28 | RFO_LF1 | Output |
| 29 | RFI_LF | Input |
| 30 | GND | Power In |
| 31 | RFI_HF | Input |
| 32 | RFO_HF | Output |
| 0 | GND | Power In |
Footprint observed
The PCB footprint contains 33 pads: pads named for all 32 numbered terminals plus an additional
GND pad with Flux Pin Number 0. This is consistent with a 32-pin VFQFN package with exposed pad, where the exposed pad is often represented as an additional thermal/ground pad.Cross-check status
Because the official IC datasheet/pinout was not publicly accessible, a strict datasheet pin-by-pin verification could not be completed. The review therefore cross-checks only against public Semtech product information and distributor/package evidence.
Matches / likely correct
- MPN
LR2021IMLTRTmatches Semtech LR2021 ordering part references found online. - Package evidence of
32-VFQFN exposed padaligns with the Flux footprint count of 33 pads: 32 signal/perimeter pads plus one exposed pad. - Symbol includes expected functional groups for an RF transceiver: SPI pins, reset/busy control, DIO pins, RF input/output pins, crystal/TCXO/NTC pins, power pins, and grounds.
- Public feature/spec summary matches the project description: low-power multi-band LoRa/FLRC transceiver.
Mismatches / items to flag
- Datasheet URL missing — no official public datasheet PDF URL was found, and the Datasheet property remains unset.
- Strict pinout verification blocked — no official Semtech pin table was accessible, so the symbol pin numbers and pin descriptions cannot be certified against the datasheet.
- Exposed pad numbering should be confirmed — the part uses an extra
GNDpad with Pin Number0. This is plausible for an exposed pad but should be confirmed against the official mechanical/pinout drawing; many datasheets label exposed pad asEP,PAD, or pin33rather than0. - Duplicate terminal name
GND— there are twoGNDterminals: pin 30 and pin 0. This may be intentional if pin 0 is the exposed pad, but the exposed pad should ideally be namedEP/GNDor similar if the datasheet supports that naming. - Pin descriptions are minimal — terminals only have broad Flux pin types; no detailed datasheet descriptions were available or stored.
Recommendation
Do not release this part as fully datasheet-verified until Semtech’s official LR2021 datasheet/package drawing is obtained, likely through Semtech resources or account-gated support. Once available, update the Datasheet URL property and verify the pin table, exposed pad numbering, and footprint dimensions against the official package drawing.
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