ST STEVAL-STWINMA2 User manual

Introduction
The STEVAL-STWINMA2 microphone array expansion adds advanced audio sensing capabilities to the STEVAL-STWINKT1B
(and STEVAL-STWINKT1) SensorTile Wireless Industrial Node (STWIN) kit for high frequency vibration monitoring applications.
The board includes four low-power, high signal-to-noise ratio (SNR) IMP23ABSU capacitive sensing microphones, supported by
a very low drop voltage, low quiescent current, and low-noise voltage regulator, ideal for battery-powered applications such as
STWIN.
The expansion board is connected via a dedicated 12-pin connector to the core system board.
The combination of STWIN and STEVAL-STWINMA2 is supported thanks to the software examples provided within the
X-CUBE-MEMSMIC1 expansion software package for STM32Cube.
The package includes one example of microphone data steaming via USB and one example of ultrasound condition monitoring
(UltrasoundFFT) that calculates the FFT of the analog microphone signal and streams the result to a PC GUI via USB.
The microphone sampling rate is set by default to 192 kHz whereas the microphone bandwidth is up to 80 kHz.
Figure 1. STEVAL-STWINMA2 board
Getting started with the industrial analog microphone array expansion for STWIN
UM3098
User manual
UM3098 - Rev 1 - May 2023
For further information contact your local STMicroelectronics sales office. www.st.com

1Features
• Analog microphone array expansion for STEVAL-STWINKT1B (and STEVAL-STWINKT1)
• Connects to the STWIN core system board through a dedicated 12-pin connector
• 3 V to 5.5 V power supply input
• 4 mm square-shaped differential microphone array
• Four IMP23ABSU high-performance, single-ended, analog, bottom-port MEMS microphones
•LDK130 300 mA low quiescent current very low noise LDO
• Ultrasound frequency response up to 80 kHz
• On-board audio-grade quad ADC
• Serial audio interface (SAI) digital output
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Features
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2Precautions for use
Important: The STEVAL.STWINMA2 evaluation board has a level of radiated emissions in Class A. Regarding immunity,
the board is not immune to indirect electrostatic discharges (electrostatic discharges applied to objects adjacent
to the board). During the ESD test the board obtained level C, meaning that the board was not damaged during
the test, but requires the intervention of the operator to reset it. When an electrostatic discharge is applied to an
adjacent object, there is the risk that the board interrupts its functioning, and in this case the intervention of the
operator is required to reset the board, meaning un-plug and re-plug the device.
Important: This kit is not immune to indirect electrostatic discharges. During the ESD test, the kit has obtained level C. This
means that the expansion board has not been damaged during the test, but the intervention of the operator was
necessary to reset it. When an electrostatic discharge is applied to an adjacent object, the board might interrupt
its functioning. In this case, the intervention of an operator is required to reset the board (that is, to unplug and
replug the power supply line).
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Precautions for use
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3How to use the board
The STEVAL-STWINMA2 has to be used with the STEVAL-STWINKT1B (or STEVAL-STWINKT1). The board
should be plugged on top of the STWIN core system board, using the CN4 connector, as shown below.
Figure 2. STWIN core system board
The shape of the connector makes it impossible to plug the board with the wrong orientation (see the figure
below).
Figure 3. STWIN core system board and STEVAL-STWINMA2 (or STEVAL-STWINMAV1)
The three firmware examples that allow you to test the development board can be found in the X-CUBE-
MEMSMIC1 package:
• AMicArray_Microphones_Streaming: microphone acquisition and streaming via USB
• AMicArray_Acoustic_SL: real-time sound source localization application using four signals acquired via
digital MEMS microphones and the AcousticSL middleware to estimate the arrival direction of an audio
source
• AMicArray_UltrasoundFFT: ultrasound condition monitoring application that calculates the FFT of the
analog microphone signal and streams the result to a PC GUI via USB
Refer to X-CUBE-MEMSMIC1 documentation for more details on the firmware package.
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How to use the board
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4Schematic diagrams
Figure 4. STEVAL-STWINMA2 schematic - Mics, VDD and connector
2
SB2
C27
a4
a1
110k
SB3
SAI_SCK
A3V
GND1
NC
2 4GND3
4
0R
3V3
b3
IN
1
A3V
MP23ABS11
SB1
GND1
2
100nF
2 3GND2
100nF
R7
M3
C24 C25
A3V
a3
SB4
GND3
3
39k 1uF
DOUT DOUT
C21
C26
5VDD
b1
M55-7001242R
GND1
0R
5VDD
100nF
SAI_SD
b2
1uF
A3V
M1
A3V
M4
MP23ABS11
1uF
1uF
1uF
M2
GND2
a2
C28
1uF
LDK130M-R
M4
2GND
b6
GND1
3
SAI_MCLK
C20
4
GND3
a6
M2
A3V
3V3 U2
C29
DOUT
VDD
5
4
MP23ABS11
5VDD
GND2
b5
R6
M3
4GND3
100nF
D3V3
SAI_FS
EN
3
3GND2
C23C22
Analog VDD
Analog Mics
Connector
3.3 to 5.5 V
MP23ABS11
ADJ/BYP
OUT 5
b4
a5
VIN
CN1
M1
VIN
3V3
I2C_SDA
I2C_SCL
DOUT
NC
SB5 0R
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Schematic diagrams

Figure 5. STEVAL-STWINMA2 schematic - ADC
ADC
D3V3
D3V3
D3V3
A3V
A3V
SAI_MCLK
SAI_SD
SAI_FS
SAI_SCK
I2C_SDA
I2C_SCL
M1
M3
M2
M4
R1
4.87k
C15
R3
U1
ADAU1978
AGND1
1
VREF
2
PLL_FILT
3
AVDD2
4
AGND2
5
PD_RST
6
MCLKIN
7
IOVDD
12
SDATAOUT1
13
SDATAOUT2
14
LRCLK
15
BCLK
16
AGND3 21
ADDR1_CIN
20
AGND4 22
NC2 23
NC5 26
NC6 27
AGND5 28
AGND6 29
NC7 30
SDA_COUT
17
NC1
8
SA_MODE
9
DVDD
10
DGND
11
SCL_CCLK
18
ADDR0_CLATCH
19
NC3 24
NC4 25
AVDD3 31
AIN1N 32
AIN1P 33
AIN2N 34
AIN2P 35
AIN3N 36
AIN3P 37
AIN4N 38
AIN4P 39
AVDD1 40
E
41
C13
100nF
C17 C2
C7
10uF
C1
39nF
C6
C12
C8
2200pF
C18
100nF
C11
R4
R2
3k
C10C4
C14
10uF
R5
Place close to AVDD1,
AVDD2, AVDD3 pins
Place close to
IOVDD
D3V3
A3V
C16
100nF
C9
100nF
C19
10uF
C5
100nF
C3
100nF
100nF
100nF 100nF
100nF
100nF
100nF
100nF100nF
47k
47k
47k
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Schematic diagrams

5Bill of materials
Table 1. STEVAL-STWINMA2 bill of materials
Item Q.ty Ref. Part/value Description Manufacturer Order code
1 1 CN1 M55-7001242R,
CN1
M55 series 12
pin connector Harwin M55-7001242R
2 1 C1 39nF, C_0402,
10%
CAP CER 39nF
10V X5R 0402 Vishay VJ0402Y393KXQCW1BC
3 18
C2, C3, C4, C5,
C6, C9, C10,
C11, C12, C13,
C15, C16, C17,
C18, C20, C23,
C25, C27
100nF, C_0402,
10%
CAP CER
0.1UF 16V X7R
0402
Wurth
Elektronik WE 885012205037
4 3 C7, C14, C19 10uF, C_0402,
20%
CAP CER 10UF
10V X5R 0402
Samsung
Electro-
Mechanics
America, Inc.
CL05A106MP8NUB8
5 1 C8 2200pF,
C_0402, 20%
CAP CER
2200PF 10V
X5R 0402
Yageo AC0402KRX7R7BB222
6 6 C21, C22, C24,
C26, C28, C29
1uF, C_0402,
10%
CAP CER 1UF
10V X5R 0402
Wurth
Elektronik WE 885012105012
7 4 M1, M2, M3, M4
IMP23ABSUTR,
RHLGA
2.65X3.5X1.08(
MAX)MM 4L
Analog bottom
port microphone
with frequency
response up to
80 kHz for
ultrasound
analysis and
predictive
maintenance
applications
ST IMP23ABSUTR
8 1 R1 4.87k,
R_0402,1%
RES SMD
4.87K OHM 1%
1/16W 0402
Yageo RC0402FR-074K87L
9 1 R2 3k, R_0402, 1%
RES SMD 3K
OHM 1% 1/16W
0402
Yageo RC0402FR-073KL
11 1 R6 39k, R_0402,
1%
RES SMD 39K
OHM 1% 1/16W
0402
TE Connectivity CRGCQ0402F39K
12 1 R7 110k, R_0402,
1%
RES SMD 110K
OHM 1% 1/16W
0402
TE Connectivity CRG0402F110K
13 2 SB1,SB4 NC, R_0402
RES SMD 0
OHM 0402 (not
mounted)
Vishay Dale CRCW04020000Z0ED
14 3 SB2, SB3, SB5 0R, R_0402 RES SMD 0
OHM 0402 Vishay Dale CRCW04020000Z0ED
15 1 U1 ADAU1978,
LFCSP-40 PCM1864 ADC AD ADAU1978
16 1 U2 LDK130M-R,
SOT323-5L
300 mA low
quiescent
current very low
noise LDO
ST LDK130M-R
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Bill of materials
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6Board versions
Table 2. STEVAL-STWINMA2 versions
PCB version Schematic diagrams Bill of materials
STEVAL$STWINMA2A (1) STEVAL$STWINMA2A schematic diagrams STEVAL$STWINMA2A bill of materials
1. This code identifies the SSTEVAL-STWINMA2 evaluation board first version. It is printed on the board PCB.
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Board versions
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7Regulatory compliance information
Notice for US Federal Communication Commission (FCC)
For evaluation only; not FCC approved for resale
FCC NOTICE - This kit is designed to allow:
(1) Product developers to evaluate electronic components, circuitry, or software associated with the kit to
determine
whether to incorporate such items in a finished product and
(2) Software developers to write software applications for use with the end product.
This kit is not a finished product and when assembled may not be resold or otherwise marketed unless all
required FCC equipment authorizations are first obtained. Operation is subject to the condition that this product
not cause harmful interference to licensed radio stations and that this product accept harmful interference. Unless
the assembled kit is designed to operate under part 15, part 18 or part 95 of this chapter, the operator of the kit
must operate under the authority of an FCC license holder or must secure an experimental authorization under
part 5 of this chapter 3.1.2
Notice for Innovation, Science and Economic Development Canada (ISED)
For evaluation purposes only. This kit generates, uses, and can radiate radio frequency energy and has not been
tested for compliance with the limits of computing devices pursuant to Industry Canada (IC) rules.
À des fins d'évaluation uniquement. Ce kit génère, utilise et peut émettre de l'énergie radiofréquence et n'a pas
été testé pour sa conformité aux limites des appareils informatiques conformément aux règles d'Industrie Canada
(IC).
Notice for European Union
This device is in conformity with the essential requirements of the Directive 2014/30/EU (EMC) and of the
Directive 2015/863/EU (RoHS).
Notice for United Kingdom
This device is in compliance with the UK Electromagnetic Compatibility Regulations 2016 (UK S.I. 2016 No. 1091)
and with the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment
Regulations 2012 (UK S.I. 2012 No. 3032).
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Regulatory compliance information
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Revision history
Table 3. Document revision history
Date Revision Changes
11-May-2023 1 Initial release.
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