NXP Semiconductors 8CH-DMIC User manual

Eight-channel DMIC Board User Manual
Supports Board Revision B
NXP Semiconductors Document identifier: 8CH-DMIC-UM
User Guide Rev. 2, 15 March 2022

Contents
Chapter 1 Overview............................................................................................... 3
1.1 Acronyms...................................................................................................................................3
1.2 Related documentation..............................................................................................................3
1.3 Kit content..................................................................................................................................4
1.4 Block diagram............................................................................................................................4
1.5 Board pictures........................................................................................................................... 4
1.6 Board features...........................................................................................................................6
1.7 Connectors................................................................................................................................ 7
1.8 Jumpers.....................................................................................................................................8
1.9 LEDs........................................................................................................................................11
Chapter 2 Functional Description.........................................................................12
2.1 Power supply...........................................................................................................................12
2.1.1 Main power supply.................................................................................................................... 12
2.1.2 Secondary power supply...........................................................................................................12
2.2 DMIC interface.........................................................................................................................12
2.2.1 DMIC configurations and signal connections............................................................................ 14
2.2.2 DMIC data switch...................................................................................................................... 21
2.2.3 DMIC clock switch.....................................................................................................................22
Appendix A Revision history................................................................................ 24
NXP Semiconductors
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 2 / 25

Chapter 1
Overview
The eight-channel DMIC plug-in board (8CH-DMIC) provides a single, a double, a triple, a quad, a hexagonal, a hexagonal
(with center mic), and an octal digital microphone (DMIC) solution. The plug-in board can be used with selected EVKs, such as
MIMXRT685-EVK, MIMXRT685-AUD-EVK, and MIMXRT595-EVK (I2C LED control may not be supported on all boards).
This document provides the detail about the 11 DMICs and their configurations, jumpers, LEDs, switches, and other interfaces
available on the board.
Example programs for use of the 8CH-DMIC board can be found in the MCUXpresso SDK software for the EVK being used (see
https://mcuxpresso.nxp.com or download the SDK directly from within MCUXpresso IDE).
1.1 Acronyms
The following table describes the acronyms and abbreviations used in this document.
Table 1. Acronyms and Abbreviations
Term Definition
ADC Analog to digital converter
CPU Central processing unit
DMIC Digital microphone
GPIO General-purpose input/output
LED Light emitting diode
MCU Microcontroller unit
PCB Printed circuit board
RF Radio frequency
SMA Subminiature version a connector
SPI Serial peripheral interface
UART Universal asynchronous receiver transmitter
1.2 Related documentation
The table below lists and explains the additional documents and resources that you can refer to for more information on 8-CH
DMIC board. Some of the documents listed below may be available only under a non-disclosure agreement (NDA). To request
access to these documents, contact your local field applications engineer (FAE) or sales representative.
Table 2. Related documentation
Document Description Link/How to access
i.MX RT685 Evaluation Board User
Manual
It describes the board layout and
settings, and also different interfaces
and peripherals available on the board.
UM11159
MIMXRT685-AUD-EVK Board User
Manual
This document provides detailed
information about the MIMXRT685
Contact NXP FAE / sales representative
Table continues on the next page...
NXP Semiconductors
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 3 / 25

Table 2. Related documentation (continued)
Document Description Link/How to access
AUD-EVK board interfaces, power
supplies, clocks, push buttons, jumpers,
and LEDs.
1.3 Kit content
The table below describes the items included in the 8-CH DMIC board kit.
Table 3. Kit contents
Item Quantity
Board hardware assembly 1
1.4 Block diagram
The figure below describes the 8-CH DMIC block diagram.
Main Board
Interface
connector
Clock
Buffers
CLK01,
CLK23,
CLK45,
CLK67
Switch
Matrix
Switch
Matrix
DCDC VDD to
3.3V Regulator
DMIC
Array
LEDC
Array
LED
Driver
DATA01,
DATA23,
DATA45,
DATA67
I2C
VDD
(1.8V to
3.3V)
Configuration Jumpers (14)
3.3V
VDD
VDD
VDD
CLK01,
CLK23,
CLK45,
CLK67
VDD
CLK01,
CLK23,
CLK45,
CLK67
DATA01,
DATA23,
DATA45,
DATA67
Figure 1. 8-CH DMIC block diagram
1.5 Board pictures
The figure below shows the top side of the board, and highlights the jumpers and LEDs available on the board.
NXP Semiconductors
Overview
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 4 / 25

J6, J7, J8, J9, J10, J11, J12, J13
J2, J3, J4
J5, J14, J15
D3
D4
D5
D2
D6
D1
D7
Figure 2. 8CH-DMIC board top side
The figure below shows the bottom side of the board, and highlights the interface connector.
NXP Semiconductors
Overview
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 5 / 25

J1
Figure 3. 8CH-DMIC board bottom side
1.6 Board features
The table below describes the DMIC board features.
NXP Semiconductors
Overview
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 6 / 25

Table 4. Main features
Board feature Processor feature used Description
Interfacing with Main board 14-pin connector used for DMIC board connection with the
main board
Power Input power ranges from 1.8 V
to 3.3 V
Typically, 1.8 V power is used for DMICs, and other interfaces,
however, 3.3 V power also works.
Note: MCP1256T DC converter to convert 1.8 V input power
supply to 3.3 V power supply for onboard LEDs.
Clock Four clocks: CLK01, CLK23,
CLK45, and CLK67
Clocks are used for 11 DMICs available on board. Clocks can
be combined with jumpers J5, J14, and J15 for use with boards
that do not have all the clocks available. Refer to Table 23
for settings.
DMIC array 11 DMICs; at most, eight DMICs are in use simultaneously.
DMIC data signals:
• DATA01
• DATA23
• DATA45
• DATA67
1.7 Connectors
Table 5. Connector detail
Part identifier Connector type Description
J1 2x7-pin connector For 8-CH DMIC board connection with the main board
The table below describes the pin description of J1 connector.
Table 6. Interface connector pin detail
Pin Signal Direction
1 VDD -
2 VDD -
3 CLK01 I
4 DATA01 O
5 CLK23 I
6 DATA23 O
7 CLK45 I
8 DATA45 O
9 CLK67 I
10 DATA67 O
Table continues on the next page...
NXP Semiconductors
Overview
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 7 / 25

Table 6. Interface connector pin detail (continued)
Pin Signal Direction
11 GND -
12 GND -
13 I2C_SCL I
14 I2C_SDA I/O
1.8 Jumpers
The following table describes the jumpers available on the board.
Table 7. Jumpers
Part
identifier
Jumper type Description Settings
J2 1x2 header Jumper for SPH0641LM4H-1
MIC 1 (U3)
• Open: SELECT pin of SPH0641LM4H-1 MIC 1 (U3) is
powered by 1.8 V and asserts data on CLK_MIC1 rising
edge (default setting)
• Shorted: SELECT pin of SPH0641LM4H-1 MIC 1 (U3) is
grounded and asserts data on CLK_MIC1 falling edge
J3 1x2 header Jumper for SPH0641LM4H-1
MIC 2 (U5)
• Open: SELECT pin of SPH0641LM4H-1 MIC2 (U5)
is powered by 1.8 V and asserts data on CLK_MIC2
rising edge
• Shorted: SELECT pin of SPH0641LM4H-1 MIC2 (U5) is
grounded and asserts data on CLK_MIC2 falling edge
(default setting)
J4 1x2 header Jumper for SPH0641LM4H-1
MIC 6 (U10)
• Open: SELECT pin of SPH0641LM4H-1 MIC6 (U10)
is powered by 1.8 V and asserts data on CLK_MIC6
rising edge
• Shorted: SELECT pin of SPH0641LM4H-1 MIC6 (U10)
is grounded and asserts data on CLK_MIC6 falling edge
(default setting)
J5 1x3 header Jumper for selection of
CLK01 or CLK23 clock signal
• 1-2 shorted: CLK01 is connected and supplies the
clock (option1)
• 2-3 shorted: CLK23 is connected and supplies the clock
(default setting)
Combination of jumpers J5, J14, and
J15 provide several clock selection
options. For detail, see Table 23.
NOTE
J6 1x2 header Used to: • Open: Data control and clock control signals for MIC
3 and MIC 9 are high, and MIC 3 and MIC 9 are not
enabled (default setting)
Table continues on the next page...
NXP Semiconductors
Overview
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 8 / 25

Table 7. Jumpers (continued)
Part
identifier
Jumper type Description Settings
• control the data from
ADG711 (U12) switch
and clock from ADG711
(U16) switch for MIC 3
• control the data from
ADG711 (U18) switch
and clock from ADG711
(U21) switch for MIC 9
• Shorted: Data control and clock control signals for MIC 3
and MIC 9 are low, and MIC 3 and MIC 9 are enabled
J7 1x2 header Used to control the data from
ADG711 (U12) switch and
clock from ADG711 (U13)
switch for MIC 2
• Open: Data control and clock control signals for MIC 2
are high, and MIC 2 is not enabled (default setting)
• Shorted: Data control and clock control signals for MIC 2
are low, and MIC 2 is enabled
J8 1x2 header Used to control the data from
ADG711 (U12) switch and
clock from ADG711 (U13)
switch for MIC 1
• Open: Data control and clock control signal for MIC 1 are
high, and MIC 1 is not enabled
• Shorted: Data control and clock control signal for MIC 1
are low, and MIC 1 is enabled (default setting)
J9 1x2 header Used to control the data from
ADG711 (U12) switch and
clock from ADG711 (U13)
switch for MIC 0
• Open: Data control and clock control signals for MIC 0
are high, and MIC 0 is not enabled
• Shorted: Data control and clock control signals for MIC 0
are low, and MIC 0 is enabled (default setting)
J10 1x2 header Used to control the data from
ADG711 (U15) switch and
clock from ADG711 (U19)
switch for MIC 6
• Open: Data control and clock control signals for MIC 6
are high, and MIC 6 is not enabled (default setting)
• Shorted: Data control and clock control signals for MIC 6
are low, and MIC 6 is enabled
J11 1x2 header Used to control the data from
ADG711 (U15) switch and
clock from ADG711 (U16)
switch for MIC 4
• Open: Data control and clock control signals for MIC 4
are high, and MIC 4 is not enabled (default setting)
• Shorted: Data control and clock control signals for MIC 4
are low, and MIC 4 is enabled
J12 1x2 header Used to:
• control the data from
ADG711 (U15) switch
and clock from ADG711
(U16) switch for MIC 3
• control the data from
ADG711 (U15) switch
and clock from ADG711
(U13) switch for MIC 2
• Open: Data control and clock control signals for MIC 2,
MIC 3, MIC 4, MIC 5, MIC 6, and MIC 10 are high, and
MIC 2, MIC 3, MIC 4, MIC 5, MIC 6, and MIC 10 are
not enabled
• Shorted: Data control and clock control signals for MIC
2, MIC 3, MIC 4, MIC 5, MIC 6, and MIC 10 are high,
and MIC 2, MIC 3, MIC 4, MIC 5, MIC 6, and MIC 10 are
enabled (default setting)
Table continues on the next page...
NXP Semiconductors
Overview
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 9 / 25

Table 7. Jumpers (continued)
Part
identifier
Jumper type Description Settings
• control the data from
ADG711 (U20) switch
and clock from ADG711
(U19) switch for MIC 6
• control the data from
ADG711 (U20) switch
and clock from ADG711
(U21) switch for MIC 10
• control the data from
ADG711 (U20) switch
and clock from ADG711
(U19) switch for MIC 5
• control the data from
ADG711 (U20) switch
and clock from ADG711
(U16) switch for MIC 4
J13 1x2 header Used to:
• control the data from
ADG711 (U18) switch
and clock from ADG711
(U19) switch for MIC 7
• control the data from
ADG711 (U18) switch
and clock from ADG711
(U21) switch for MIC 8
• control the data from
ADG711 (U18) switch
and clock from ADG711
(U21) switch for MIC 10
•Open: Data control and clock control signals for MIC 7,
MIC 8, and MIC 10 are high, and MIC 7, MIC 8, and MIC
10 are not enabled (default setting)
• Shorted: Data control and clock control signals for MIC 7,
MIC 8, and MIC 10 are high, and MIC 7, MIC 8, and MIC
10 are enabled
J14 1x3 header Jumper for selection of
CLK01 or CLK45 clock signal
• 1-2 shorted: CLK01 is connected and supplies the
clock (option1)
• 2-3 shorted: CLK45 is connected and supplies the clock
(default setting)
Combination of jumpers J5, J14, and
J15 provide several clock selection
options. For detail, see Table 23.
NOTE
J15 1x3 header Jumper for selection of
CLK45 or CLK67 clock signal
• 1-2 shorted: CLK45 is connected and supplies the clock
(default setting)
• 2-3 shorted: CLK67 is connected and supplies the
clock (Option1)
Table continues on the next page...
NXP Semiconductors
Overview
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 10 / 25

Table 7. Jumpers (continued)
Part
identifier
Jumper type Description Settings
Combination of jumpers J5, J14, and
J15 provide several clock selection
options. For detail, see Table 23.
NOTE
1.9 LEDs
Total of eight LEDs are available on the 8-CH DMIC board. The table below describes the DMIC board LEDs.
Table 8. LEDs
Part identifier LED color LED Placement Description (When LED is ON)
D1 Blue Available on top of the plug
in board
User Programmable LEDs
D2 Blue Available on top of the plug
in board
D3 Blue Available on top of the plug
in board
D4 Blue Available on top of the plug
in board
D5 Blue Available on top of the plug
in board
D6 Blue Available on top of the plug
in board
D7 Red Available on top of the plug
in board next to the interface
connector (J1)
NXP Semiconductors
Overview
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 11 / 25

Chapter 2
Functional Description
This chapter describes the features and different interfaces of 8-CH DMIC board.
2.1 Power supply
This section describes the power supply on 8-CH DMIC board.
2.1.1 Main power supply
The 8-CH DMIC board can accept from 1.8 V up to 3.6 V for operation from the main board through J1 interface connector.
2.1.2 Secondary power supply
The MCP1256T device (U35) generates a 3.3 V output voltage from 1.8V input supply. The 3.3 V power supply is used for:
• Onboard LEDs [D1:D7]
• SX1502I087TRT GPIO expander used for LEDs
2.2 DMIC interface
A total of 11 DMICs are available on the DMIC board, however, at most, eight DMICs are in use simultaneously.
The below figure describes the different DMICs placement on the board.
NXP Semiconductors
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 12 / 25

MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
6MIC, 7MIC, 8MIC Config:
MIC0, MIC1, MIC2, MIC3,
MIC4, MIC5, MIC6, MIC10
2MIC, 3MICA, 3MICC Config:
MIC0, MIC3, MIC6, MIC9 3MICB, 4MICA Config:
MIC0, MIC2, MIC4, MIC6
4MICB, 5MIC Config:
MIC1, MIC2, MIC7,
MIC8, MIC10
Table 9. DMIC Array
Part identifier Device Mic Description
U1 SPH0641LM4H-1 MIC0 Asserts data on CLK_MIC0 falling edge
U3 MIC1 Asserts data on CLK_MIC1 rising and falling
edge depending upon jumper J2 setting
U2 MIC8 Asserts data on CLK_MIC8 rising edge
U4 MIC9 Asserts data on CLK_MIC9 falling edge
U5 MIC2 Asserts data on CLK_MIC2 rising and falling
edge depending upon jumper J3 setting
U6 MIC3 Asserts data on CLK_MIC3 rising edge
U7 MIC10 Asserts data on CLK_MIC10 rising edge
Table continues on the next page...
NXP Semiconductors
Functional Description
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 13 / 25

Table 9. DMIC Array (continued)
Part identifier Device Mic Description
U8 MIC4 Asserts data on CLK_MIC4 falling edge
U9 MIC5 Asserts data on CLK_MIC5 rising edge
U10 MIC6 Asserts data on CLK_MIC6 rising and falling
edge depending upon jumper J4 setting
U11 MIC7 Asserts data on CLK_MIC7 falling edge
2.2.1 DMIC configurations and signal connections
Ten different DMIC configurations are possible on the board as follows:
• 2DMIC
• 3DMIC[A]
• 3DMIC[B]
• 3DMIC[C]
• 4DMIC[A]
• 4DMIC[B]
• 5DMIC
• 6DMIC
• 7DMIC
• 8DMIC
The below tables describe the different DMIC configurations and respective data and clock signals that are active for
these configurations.
2DMIC configuration
Table 10. 2DMIC configuration
Part identifier DMIC Active Data and Clock signal
U1 DMIC0 DATA01 and CLK01
U6 DMIC3
The figure below shows the 2DDMIC configuration.
NXP Semiconductors
Functional Description
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 14 / 25

MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 4. 2DMIC configuration
3DMIC[A] configuration
Table 11. 3DMIC[A] configuration
Part identifier DMIC Active Data and Clock signal
U1 DMIC0 DATA01 and CLK01
U6 DMIC3
U4 DMIC9 DATA23 and CLK23
The figure below shows the 3DMIC[A] configuration.
MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 5. 3DMIC[A] configuration
3DMIC[B] configuration
Table 12. 3DMIC[B] configuration
Part identifier DMIC Active Data and Clock signal
U1 DMIC0 DATA01 and CLK01
Table continues on the next page...
NXP Semiconductors
Functional Description
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 15 / 25

Table 12. 3DMIC[B] configuration (continued)
Part identifier DMIC Active Data and Clock signal
U5 DMIC2
U8 DMIC4 DATA23 and CLK23
The figure below shows the 3DMIC[B] configuration.
MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 6. 3DMIC[B] configuration
3DMIC[C] configuration
Table 13. 3DMIC[C] configuration
Part identifier DMIC Active Data and Clock signal
U1 DMIC0 DATA01 and CLK01
U6 DMIC3
U10 DMIC6 DATA23 and CLK23
The figure below shows the 3DMIC[C] configuration.
MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 7. 3DMIC[C] configuration
NXP Semiconductors
Functional Description
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 16 / 25

4DMIC[A] configuration
Table 14. 4DMIC[A] configuration
Part identifier DMIC Active Data and Clock signal
U1 DMIC0 DATA01 and CLK01
U5 DMIC2
U8 DMIC4 DATA23 and CLK23
U10 DMIC6
The figure below shows the 4DMIC[A] configuration.
MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 8. 4DMIC[A] configuration
4DMIC[B] configuration
Table 15. 4DMIC[B] configuration
Part identifier DMIC Active Data and Clock signal
U3 DMIC1 DATA01 and CLK01
U5 DMIC2
U11 DMIC7 DATA23 and CLK23
U2 DMIC8
The figure below shows the 4DMIC[B] configuration.
NXP Semiconductors
Functional Description
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 17 / 25

MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 9. 4DMIC[B] configuration
5DMIC configuration
Table 16. 5DMIC configuration
Part identifier DMIC Active Data and Clock signal
U3 DMIC1 DATA01 and CLK01
U5 DMIC2
U11 DMIC7 DATA23 and CLK23
U2 DMIC8
U7 DMIC10 DATA45 and CLK45
The figure below shows the 5DMIC configuration.
MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 10. 5DMIC configuration
NXP Semiconductors
Functional Description
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 18 / 25

6DMIC configuration
Table 17. 6DMIC configuration
Part identifier DMIC Active Data and Clock signal
U1 DMIC0 DATA01 and CLK01
U3 DMIC1
U5 DMIC2 DATA23 and CLK23
U6 DMIC3
U8 DMIC4 DATA45 and CLK45
U9 DMIC5
The figure below shows the 6DMIC configuration.
MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 11. 6DMIC configuration
7DMIC configuration
Table 18. 7DMIC configuration
Part identifier DMIC Active Data and Clock signal
U1 DMIC0 DATA01 and CLK01
U3 DMIC1
U5 DMIC2 DATA23 and CLK23
U6 DMIC3
U8 DMIC4 DATA45 and CLK45
U9 DMIC5
U10 DMIC6 DATA67 and CLK67
The figure below shows the 7DMIC configuration.
NXP Semiconductors
Functional Description
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 19 / 25

MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 12. 7DMIC configuration
8DMIC configuration
Table 19. 8DMIC configuration
Part identifier DMIC Active Data and Clock signal
U1 DMIC0 DATA01 and CLK01
U3 DMIC1
U5 DMIC2 DATA23 and CLK23
U6 DMIC3
U8 DMIC4 DATA45 and CLK45
U9 DMIC5
U10 DMIC6 DATA67 and CLK67
U7 DMIC10
The figure below shows the 8DMIC configuration.
MIC0
MIC1 MIC2
MIC3
MIC4MIC5
MIC6
MIC7 MIC8
MIC9
MIC10
- Indicates active DMIC
- Indicates inctive DMIC
Figure 13. 8DMIC configuration
NXP Semiconductors
Functional Description
Eight-channel DMIC Board User Manual, Rev. 2, 15 March 2022
User Guide 20 / 25