component
WM8940CGEFL
Public Made by Adomby adom
Cirrus Logic Audio Interface ICs, QFN-24(4x4). Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
main
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"title": "WM8940CGEFL",
"brief": "Cirrus Logic Audio Interface ICs, QFN-24(4x4). Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
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"package": "QFN-24(4x4)",
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"category": "Communication Interface Chip/UART/485/232",
"subcategory": "Audio Interface ICs",
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"pins": [
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"number": "1",
"name": "MICBIAS",
"type": "power_out",
"description": "Microphone bias output for electret microphones."
},
{
"number": "2",
"name": "AVDD",
"type": "power_in",
"description": "Analogue supply, 2.5V to 3.6V, must be >= digital supply voltages."
},
{
"number": "3",
"name": "AGND",
"type": "power_in",
"description": "Analogue ground; the QFN ground paddle is recommended to be connected to analogue ground."
},
{
"number": "4",
"name": "DCVDD",
"type": "power_in",
"description": "Digital core supply, 1.71V to 3.6V, must be <= DBVDD."
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{
"number": "5",
"name": "DBVDD",
"type": "power_in",
"description": "Digital input/output buffer supply, 1.71V to 3.6V, must be >= DCVDD."
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{
"number": "6",
"name": "DGND",
"type": "power_in",
"description": "Digital ground, must be within 0.3V of analogue ground."
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{
"number": "7",
"name": "ADCDAT",
"type": "output",
"description": "ADC digital audio data output."
},
{
"number": "8",
"name": "DACDAT",
"type": "input",
"description": "DAC digital audio data input."
},
{
"number": "9",
"name": "FRAME",
"type": "bidirectional",
"description": "DAC and ADC sample rate clock or frame synch, input in slave mode and output in master mode."
},
{
"number": "10",
"name": "BCLK",
"type": "bidirectional",
"description": "Digital audio port clock, input in slave mode and output in master mode."
},
{
"number": "11",
"name": "MCLK",
"type": "input",
"description": "Master clock input."
},
{
"number": "12",
"name": "CSB/GPIO",
"type": "bidirectional",
"description": "3-wire control interface chip select or GPIO pin."
},
{
"number": "13",
"name": "SCLK",
"type": "input",
"description": "3-wire control interface clock input / 2-wire control interface clock input."
},
{
"number": "14",
"name": "SDIN",
"type": "bidirectional",
"description": "3-wire control interface data input / 2-wire control interface data input."
},
{
"number": "15",
"name": "MODE/GPIO",
"type": "bidirectional",
"description": "Control interface mode selection (low = 2-wire, high or Hi-Z = 3-wire) or GPIO pin."
},
{
"number": "16",
"name": "MONOOUT",
"type": "output",
"description": "Mono line output."
},
{
"number": "17",
"name": "SPKOUTP",
"type": "output",
"description": "Speaker output positive."
},
{
"number": "18",
"name": "SPKGND",
"type": "power_in",
"description": "Speaker ground."
},
{
"number": "19",
"name": "SPKOUTN",
"type": "output",
"description": "Speaker output negative."
},
{
"number": "20",
"name": "SPKVDD",
"type": "power_in",
"description": "Speaker supply, 2.5V to 3.6V, must be >= digital supply voltages."
},
{
"number": "21",
"name": "AUX",
"type": "input",
"description": "Auxiliary analogue input."
},
{
"number": "22",
"name": "VMID",
"type": "passive",
"description": "Decoupling for midrail reference voltage."
},
{
"number": "23",
"name": "MICN",
"type": "input",
"description": "Microphone negative input (common mode)."
},
{
"number": "24",
"name": "MICP",
"type": "input",
"description": "Microphone positive input."
},
{
"number": "25",
"name": "EP",
"type": "passive",
"description": "Exposed pad (from the footprint; not named in the datasheet pin table)."
}
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"guards": "pin_guards 0.1: passed",
"guard_notes": [
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"pages_sent": 17,
"cost_usd": 0.1422,
"at": "2026-10-30T11:50:31"
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"sha256": "c8f0e2097c3b34ff",
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"cad": "KiCad official (CC-BY-SA 4.0)",
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"described": 25,
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"metadata": {
"specs": {
"Manufacturer": "Cirrus Logic",
"Package": "QFN-24(4x4)",
"Category": "Communication Interface Chip/UART/485/232",
"Pins": "25"
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"name": "Digital supply range (Core)",
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"name": "Analogue supplies range",
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{
"name": "Operating temperature range",
"symbol": "TA",
"kind": "absolute_maximum",
"unit": "°C",
"min": -25,
"typ": null,
"max": 85,
"conditions": "",
"source_page": 7,
"source": "datasheet"
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{
"name": "Storage temperature after soldering",
"symbol": "",
"kind": "absolute_maximum",
"unit": "°C",
"min": -65,
"typ": null,
"max": 150,
"conditions": "",
"source_page": 7,
"source": "datasheet"
},
{
"name": "Maximum Input PGA Programmable Gain",
"symbol": "",
"kind": "electrical",
"unit": "dB",
"min": 33.25,
"typ": 35.25,
"max": 37.25,
"conditions": "Gain adjusted by INPPGAVOL",
"source_page": 8,
"source": "datasheet"
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{
"name": "Minimum Input PGA Programmable Gain",
"symbol": "",
"kind": "electrical",
"unit": "dB",
"min": -14,
"typ": -12,
"max": -10,
"conditions": "Gain adjusted by INPPGAVOL",
"source_page": 8,
"source": "datasheet"
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{
"name": "Maximum Gain from AUX input PGA mixers",
"symbol": "",
"kind": "electrical",
"unit": "dB",
"min": 4,
"typ": 6,
"max": 7.5,
"conditions": "Gain adjusted by AUX2BOOSTVOL",
"source_page": 8,
"source": "datasheet"
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{
"name": "Minimum Gain from AUX input PGA mixers",
"symbol": "",
"kind": "electrical",
"unit": "dB",
"min": -14,
"typ": -12,
"max": -9,
"conditions": "Gain adjusted by AUX2BOOSTVOL",
"source_page": 8,
"source": "datasheet"
},
{
"name": "ADC Signal to Noise Ratio",
"symbol": "SNR",
"kind": "electrical",
"unit": "dB",
"min": 88,
"typ": 91,
"max": null,
"conditions": "A-weighted, AVDD=3.3V",
"source_page": 8,
"source": "datasheet"
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{
"name": "ADC Total Harmonic Distortion",
"symbol": "THD",
"kind": "electrical",
"unit": "dB",
"min": null,
"typ": -80,
"max": -75,
"conditions": "-1dBV Input, AVDD=3.3V",
"source_page": 8,
"source": "datasheet"
},
{
"name": "ADC Total Harmonic Distortion + Noise",
"symbol": "THD+N",
"kind": "electrical",
"unit": "dB",
"min": null,
"typ": -75,
"max": -68,
"conditions": "-1dBV Input, AVDD=3.3V",
"source_page": 8,
"source": "datasheet"
},
{
"name": "DAC to Mono Output Signal to Noise Ratio",
"symbol": "SNR",
"kind": "electrical",
"unit": "dB",
"min": 93,
"typ": 98,
"max": null,
"conditions": "A-weighted, AVDD=SPKVDD=3.3V",
"source_page": 9,
"source": "datasheet"
},
{
"name": "DAC to Mono Output THD",
"symbol": "THD",
"kind": "electrical",
"unit": "dBFS",
"min": null,
"typ": -80,
"max": -75,
"conditions": "0dBFS input, AVDD=SPKVDD=3.3V",
"source_page": 9,
"source": "datasheet"
},
{
"name": "DAC to Mono Output THD+N",
"symbol": "THD+N",
"kind": "electrical",
"unit": "dBFS",
"min": null,
"typ": -78,
"max": -74,
"conditions": "0dBFS input, AVDD=SPKVDD=3.3V",
"source_page": 9,
"source": "datasheet"
},
{
"name": "MIC PGA to Speaker Output Signal to Noise Ratio",
"symbol": "SNR",
"kind": "electrical",
"unit": "dB",
"min": 94,
"typ": 99,
"max": null,
"conditions": "A-weighted, AVDD=SPKVDD=3.3V",
"source_page": 9,
"source": "datasheet"
},
{
"name": "MIC PGA to Speaker Output THD",
"symbol": "THD",
"kind": "electrical",
"unit": "dBFS",
"min": null,
"typ": -90,
"max": -85,
"conditions": "full-scale signal, AVDD=SPKVDD=3.3V",
"source_page": 9,
"source": "datasheet"
},
{
"name": "MIC PGA to Speaker Output THD+N",
"symbol": "THD+N",
"kind": "electrical",
"unit": "dBFS",
"min": null,
"typ": -87,
"max": -82,
"conditions": "full-scale signal, AVDD=SPKVDD=3.3V",
"source_page": 9,
"source": "datasheet"
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{
"name": "Speaker Output (BTL 8 ohm) Signal to Noise Ratio",
"symbol": "SNR",
"kind": "electrical",
"unit": "dB",
"min": 93.5,
"typ": 98,
"max": null,
"conditions": "A-weighted, SPKVDD=3.3V",
"source_page": 9,
"source": "datasheet"
},
{
"name": "Headphone Output Signal to Noise Ratio",
"symbol": "SNR",
"kind": "electrical",
"unit": "dB",
"min": 95,
"typ": 99,
"max": null,
"conditions": "A-weighted, SPKVDD=3.3V",
"source_page": 9,
"source": "datasheet"
},
{
"name": "Digital Input HIGH Level",
"symbol": "VIH",
"kind": "electrical",
"unit": "V",
"min": 0.7,
"typ": null,
"max": null,
"conditions": "x DBVDD",
"source_page": 9,
"source": "datasheet"
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{
"name": "Digital Input LOW Level",
"symbol": "VIL",
"kind": "electrical",
"unit": "V",
"min": null,
"typ": null,
"max": 0.3,
"conditions": "x DBVDD",
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{
"name": "Digital Output HIGH Level",
"symbol": "VOH",
"kind": "electrical",
"unit": "V",
"min": 0.9,
"typ": null,
"max": null,
"conditions": "IOL=1mA, x DBVDD",
"source_page": 9,
"source": "datasheet"
},
{
"name": "Digital Output LOW Level",
"symbol": "VOL",
"kind": "electrical",
"unit": "V",
"min": null,
"typ": null,
"max": 0.1,
"conditions": "IOH-1mA, x DBVDD",
"source_page": 9,
"source": "datasheet"
},
{
"name": "Total Delay ADC analogue input to digital audio interface output",
"symbol": "",
"kind": "timing",
"unit": "fs",
"min": 28,
"typ": 30,
"max": 32,
"conditions": "Wind noise filter disabled; printed as 28/fs, 30/fs, 32/fs",
"source_page": 83,
"source": "datasheet"
},
{
"name": "Total Delay audio interface input to DAC analogue output",
"symbol": "",
"kind": "timing",
"unit": "fs",
"min": 33,
"typ": 35,
"max": 37,
"conditions": "Wind noise filter disabled; printed as 33/fs, 35/fs, 37/fs",
"source_page": 83,
"source": "datasheet"
},
{
"name": "MICN input resistance",
"symbol": "",
"kind": "electrical",
"unit": "kΩ",
"min": null,
"typ": 2,
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"conditions": "INPPGAVOL = +35.25dB",
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{
"name": "MICN input resistance",
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{
"name": "MICN input resistance",
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{
"name": "MICP input resistance",
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{
"name": "AUX Input Resistance",
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"conditions": "Input boost and mixer enabled, at 0dB gain",
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{
"name": "Input PGA equivalent input noise",
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"conditions": "INPPGAVOL = +35.25dB, No input signal, 0 to 20kHz",
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{
"name": "Programmable Gain Step Size",
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{
"name": "Input PGA Mute Attenuation",
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{
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{
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{
"name": "Speaker PSRR",
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