component
SI4355-B1A-FMR
Public Made by Adomby adom
SKYWORKS SILICON LABS RF Transceiver ICs, QFN-20-EP(3x3). Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
main
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{
"slug": "si4355-b1a-fmr",
"version": "0.1.0",
"type": "component",
"description": "SKYWORKS SILICON LABS RF Transceiver ICs, QFN-20-EP(3x3). Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
"tags": [
"component",
"rf and wireless",
"si4355-b1a-fmr",
"factory-2.0.0",
"extractor-text"
],
"dependencies": {},
"hero": {
"type": "image",
"path": "docs/hero.png"
},
"files": [
"page.json",
"README.md",
"si4355-b1a-fmr.kicad_sym",
"si4355-b1a-fmr.kicad_mod",
"si4355-b1a-fmr.glb",
"si4355-b1a-fmr.step",
"si4355-b1a-fmr.lbr",
"docs/hero.png",
"docs/si4355-b1a-fmr-datasheet.pdf",
"viewers/symbol.html",
"viewers/footprint.html",
"si4355-b1a-fmr-hero.glb",
"si4355-b1a-fmr-hero.overlay.json",
"si4355-b1a-fmr-etched.glb"
],
"component": {
"mpn": "SI4355-B1A-FMR",
"manufacturer": "SKYWORKS SILICON LABS",
"package": "QFN-20-EP(3x3)",
"pin_count": 21,
"category": "RF And Wireless",
"subcategory": "RF Transceiver ICs",
"datasheet": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588893791717220352",
"parts": {
"symbol": "si4355-b1a-fmr.kicad_sym",
"footprint": "si4355-b1a-fmr.kicad_mod",
"model_3d": "si4355-b1a-fmr-hero.glb",
"model_3d_plain": "si4355-b1a-fmr-etched.glb",
"model_3d_step": "si4355-b1a-fmr-etched.step",
"model_3d_step_plain": "si4355-b1a-fmr.step",
"lbr": "si4355-b1a-fmr.lbr"
},
"distributor_links": {
"lcsc": "C2654599",
"digikey": "336-4141-2-ND",
"mouser": "634-SI4355-B1A-FMR"
},
"distributor_check": {
"checked_at": "2026-10-20T09:51:17Z",
"source": "Component Ocean /api/assign-pns",
"digikey": {
"pn": "336-4141-2-ND",
"status": "found",
"lifecycle": "Not For New Designs"
},
"mouser": {
"pn": "634-SI4355-B1A-FMR",
"status": "found",
"lifecycle": "Not Recommended for New Designs"
}
},
"pins": [
{
"number": "1",
"name": "GND",
"type": "power_in",
"description": "Ground pin."
},
{
"number": "2",
"name": "SDN",
"type": "input",
"description": "Shutdown input (0 to VDD V): SDN = 1 puts the part in shutdown mode and all register contents are lost, while SDN = 0 selects all other modes."
},
{
"number": "3",
"name": "RXp",
"type": "input",
"description": "Differential RF receiver input pin (RXp/RXn pair)."
},
{
"number": "4",
"name": "RXn",
"type": "input",
"description": "Differential RF receiver input pin (RXp/RXn pair)."
},
{
"number": "5",
"name": "NC",
"type": "unconnected",
"description": "No connect pin."
},
{
"number": "6",
"name": "GND",
"type": "power_in",
"description": "Ground pin."
},
{
"number": "7",
"name": "VDD",
"type": "power_in",
"description": "Supply voltage; recommended supply range is 1.8 to 3.6 V."
},
{
"number": "8",
"name": "VDD",
"type": "power_in",
"description": "Supply voltage; recommended supply range is 1.8 to 3.6 V."
},
{
"number": "9",
"name": "GND",
"type": "power_in",
"description": "Ground pin."
},
{
"number": "10",
"name": "GPIO0",
"type": "bidirectional",
"description": "General purpose digital I/O; I/O drive voltage VGPIO is 1.8 to 3.6 V."
},
{
"number": "11",
"name": "GPIO1",
"type": "bidirectional",
"description": "General purpose digital I/O; I/O drive voltage VGPIO is 1.8 to 3.6 V."
},
{
"number": "12",
"name": "nIRQ",
"type": "output",
"description": "Interrupt status output: nIRQ = 0 indicates an interrupt event has occurred, and the interrupt status register gives the event details."
},
{
"number": "13",
"name": "SCLK",
"type": "input",
"description": "Serial clock input (0 to VDD V) providing the serial data clock for the 4-line serial data bus."
},
{
"number": "14",
"name": "SDO",
"type": "output",
"description": "Serial data output (0 to VDD V) providing readback of internal control registers."
},
{
"number": "15",
"name": "SDI",
"type": "input",
"description": "Serial data input (0 to VDD V) carrying the serial data stream for the 4-line serial data bus."
},
{
"number": "16",
"name": "nSEL",
"type": "input",
"description": "Serial interface select input (0 to VDD V) providing the select/enable function for the 4-line serial data bus."
},
{
"number": "17",
"name": "XOUT",
"type": "output",
"description": "Crystal oscillator output."
},
{
"number": "18",
"name": "XIN",
"type": "input",
"description": "Crystal oscillator input; no DC bias is required, but if used it should be set to 7 V as printed in the datasheet."
},
{
"number": "19",
"name": "GPIO2",
"type": "bidirectional",
"description": "General purpose digital I/O; I/O drive voltage VGPIO is 1.8 to 3.6 V."
},
{
"number": "20",
"name": "GPIO3",
"type": "bidirectional",
"description": "General purpose digital I/O; I/O drive voltage VGPIO is 1.8 to 3.6 V."
},
{
"number": "21",
"name": "EP",
"type": "passive",
"description": "Exposed pad (from the footprint; not named in the datasheet pin table)."
}
],
"provenance": {
"extractor": "extract_pins 0.3",
"factory_chain": {
"factory": "2.0.0",
"extractor": "extract_pins 0.3",
"primary_model": "claude-haiku-5-5",
"primary_mode": "text",
"consensus_model": "claude-sonnet-5-5",
"consensus": "agreed",
"guards": "pin_guards 0.1: passed",
"guard_notes": [
"extractor flagged: The requested package hint is QFN-20-EP(3x3), but the datasheet text lists only pins 1 to 20 and doe; The MPN suffix -FMR is the tape-and-reel form of the Si4355-B1A-FM listed in the ordering section (t; Pin 18 (XIN) description says 'should be set to 7 V'. This value is printed as-is in the source text",
"exposed pad 21 added from the footprint",
"2/21 pins cited to the wrong page (name found elsewhere): ['17:XOUT@p28', '18:XIN@p28']"
],
"pages_sent": 11,
"cost_usd": 0.0493,
"at": "2026-10-20T09:51:04"
},
"datasheet": {
"url": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588893791717220352",
"pages": 34,
"sha256": "0167ca134eeaee26",
"source_tier": "lcsc"
},
"cad": "KiCad official (CC-BY-SA 4.0)",
"pins": {
"total": 21,
"described": 21,
"cites_pages": true,
"refuses_to_fabricate": true
}
},
"viewers": {
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"footprint": "viewers/footprint.html"
},
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"role": "plain",
"up": "Z",
"units": "mm",
"origin": "footprint origin = pad-pattern centre",
"seat": "z = 0",
"extents_mm": [
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],
"zmin_mm": 0.0,
"centre_offset_mm": 0.0,
"footprint_binding": "identity",
"sha256": "0ee4e1082236390795238cd34b082d96efd160d6292c636cc40201a5a30cdc63",
"checked": "2026-10-20",
"checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
},
{
"file": "si4355-b1a-fmr-etched.step",
"role": "eda",
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"origin": "footprint origin = pad-pattern centre",
"seat": "z = 0",
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}
]
}
}