Nuvoton NAU88C22 User manual

NAU88C22 Demo Board User Manual
MAY. 25, 2021 Page 1of 21 Rev1.0
NAU88C22 Demo Board
User Manual
The PCB name: EVB-NAU88C22YG_V1.0
Ordering P/N: NL-NAU88C22
The information described in this document is the exclusive intellectual property of
Nuvoton Technology Corporation and shall not be reproduced without permission from Nuvoton.
Nuvoton is providing this document only for reference purposes of microcontroller based system design.
Nuvoton assumes no responsibility for errors or omissions.
All data and specifications are subject to change without notice.
For additional information or questions, please contact: Nuvoton Technology Corporation.
www.nuvoton.com

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TABLE OF CONTENTS
1OVERVIEW ................................................................................ 5
2INTRODUCTION.......................................................................... 6
2.1 Top View ....................................................................................... 7
2.2 Input / Output.................................................................................. 8
2.3 Jumpers ...................................................................................... 10
2.4 Schematic.................................................................................... 15
2.5 Bare Board................................................................................... 17
3CONNECTED TO AUDIO CONTROL BOARD .................................... 18
4APPLICATION........................................................................... 19
5REVISION HISTORY................................................................... 21

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List of Figure
Figure 2-1 NAU88C22 Demo Board......................................................................6
Figure 2.1-1 Top View...........................................................................................7
Figure 2.2-1 Input / Output....................................................................................8
Figure 2.3-1 Jumpers..........................................................................................10
Figure 2.4-1 Schematic (page 1).........................................................................15
Figure 2.4-2 Schematic (page 2).........................................................................16
Figure 2.5-1 Top View of Bare Board..................................................................17
Figure 3-1 Connection Audio Control Board .......................................................18
Figure 3-2 Signal Path ........................................................................................18

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List of Tables
Table 2.1-1 Main Components..............................................................................7
Table 2.2-1 Input / Output.....................................................................................9
Table 2.3-1 Jumpers...........................................................................................14

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1 OVERVIEW
The NAU88C22 is a low power, high quality CODEC for portable and general purpose audio
applications. In addition to precision 24-bit stereo ADCs and DACs, this device integrates a broad
range of additional functions to simplify implementation of complete audio system solutions. The
NAU88C22 includes drivers for speaker, headphone, and differential or stereo line outputs, and
integrates preamps for stereo differential microphones, significantly reducing external component
requirements. Also, a fractional PLL is available to accurately generate any audio sample rate for the
CODEC using any commonly available system clock from 8MHz through 33MHz.

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2 INTRODUCTION
The NAU88C22 Demo Board is designed to allow a thorough evaluation of the audio codec.
Figure 2-1 NAU88C22 Demo Board

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2.1 Top View
Figure 2.1-1 Top View
Table 2.1-1 Main Components
Name
Description
NAU88C22YG
Audio CODEC

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2.2 Input / Output
Figure 2.2-1 Input / Output

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Table 2.2-1 Input / Output
Name
Description
J_CB
Pin 1
I2S Interface
MCLK, Master Clock
Pin 11
I2C Interface
SDA
Pin 3
BCLK, Bit Clock
Pin 13
SCL
Pin 5
DACIN
Pin15
Power.
Provide power
to Demo board.
VDDIO
Pin 7
ADCOUT
Pin 17
VDD1.8
Pin 9
FS ,Frame Sync
Pin 19
VDD3.3
Pin 21
VDD5
JP_I2S
These pins can also be I2S interface
Pin 1
MCLK, Master Clock
Pin 3
BCLK, Bit Clock
Pin 5
DACIN
Pin 7
ADCOUT
Pin 9
FS ,Frame Sync
JP_I2C_SPI
Pin1 and Pin2 are I2C interface.
In addition, this connector can be an SPI interface.
Pin 1
SDL
Pin 2
SCA
Pin 3
GND
Pin 4
CSB/GPIO1
Pin 5
RLIN/GPIO3
MIC
Microphone input.
Headphone
Headphone output.
Speaker
Speaker out.
AUXIN
Auxiliary input.
AUXOUT
Auxiliary output.

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2.3 Jumpers
Figure 2.3-1 Jumpers

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Name
Pin definition
Description
JP_VDDBC
VDDB and VDDC
voltage selection
Short
1-2 (default)
2-3
VDDBC
VDDBC uses
voltage of 3.3V
VDDBC uses
voltage of 3.3V
JP_VDDSPK
Speaker power
supply voltage
selection
Short
1-2 (default)
2-3
VDDSPK
VDDSPK uses
voltage of 3.3V
VDDSPK uses
voltage of 5V
JP_VDDA
VDDA power
source selection
Short (default)
Open
VDDA
Using power from
JP_I2S_CB
Can use external power
to connect to pin2

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JP_I2S_CB
I2C and I2S
signal selection
Short (default)
Open
Pin 1-2 MCLK
Using signal from J_CB
Can use external signal
to connect to pin1
Pin 3-4 BCLK
Can use external signal
to connect to pin3
Pin 5-6 SDI
Can use external signal
to connect to pin5
Pin 7-8 SDO
Can use external signal
to connect to pin7
Pin 9-10 LRCLK
Can use external signal
to connect to pin9
Pin 11-12 SCL
Can use external signal
to connect to pin11
Pin 13-14 SDA
Can use external signal
to connect to pin13
Pin 15-16 GNG
JP_OSC
Onboard OSC
selection
Short
Open (default)
VDDA
MCLK signal source is
Onboard OSC
Note：If you want to
use Onboard OSC, you
need to make sure that
J_CB has no signal
input, or open
JP_I2S_CB pin1-2
MCLK signal source is
JP_I2S_CB

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JP_LMICP
Left Mic channel
source selection
Short
Open (default)
JP_LMICP
MIC input
Differential intput
Short 1-2
(default)
Short 2-3
Open
JP_LMICN
Sing-end input
MIC input
Differential intput
JP_LMICN
JP_RMICP
Right Mic channel
source selection
Short
Open (default)
JP_LMICP
MIC input
Differential intput
Short 1-2
(default)
Short 2-3
Open
JP_LMICN
Sing-end input
MIC input
Differential intput
JP_RMICN

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JP_MODE
Control interface
selection
Short (default)
Open
VDDA
Using power from
JP_I2S_CB
Can use external power
to connect to pin2
Table 2.3-1 Jumpers

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2.4 Schematic
Figure 2.4-1 Schematic (page 1)

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Figure 2.4-2 Schematic (page 2)

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2.5 Bare Board
Figure 2.5-1 Top View of Bare Board

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3 CONNECTED TO AUDIO CONTROL BOARD
If there is Nuvoton's Audio Control Board, NAU88C22 Demo Board can be used with Audio Control
Board (USB_I2C_I2S_Control_Board_V1.1). When the Audio Control Board is connected to the
NAU88C22 Demo Board, the PC or USB host can use the GUI to control the NAU88C22 Demo Board
and know the status of the NAU88C22 Demo Board.
Figure 3-1 Connection Audio Control Board
Signal path:
Figure 3-2 Signal Path
Board setting SOP:
Reference Figure 3-1
Step1: Connect J_CB of the NAU88C22 Demo Board to J5 of the Audio Control Board.
Step2: Connect CN2 of the Audio Control Board to PC or USB host via USB cable.

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4 APPLICATION
4-1 SPI
3-wire
a. JP_MODE 2-3 short
4-wire
a. JP_MODE 2-3 short
b. JP_GPIO3 1-2 short (for 4-wire SPI)
c. JP_RLIN/GPIO3 NC (for 4-wire SPI)
4-2 RMICP and RMICN
Differential input
a. JP_RMICN NC
b. JP_RMICP NC
Single-end input
a. JP_RMICN 1-2 short
b. JP_RMICP NC
MIC input
a. JP_RMICN 2-3 short
b. JP_RMICP 1-2 short
4-3 LMICP and LMICN
Differential input
a. JP_LMICN NC
b. JP_LMICP NC
Single-end input
a. JP_LMICN 1-2 short
b. JP_LMICP NC

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MIC input
a. JP_LMICN 2-3 short
b. JP_LMICP 1-2 short
4-4 Line level input
a. JP_LLIN/GPIO2 1-2 short
b. JP_RLIN/GPIO3 1-2 short
4-5 MCLK
MCLK from control board
a. JP_OSC NC
b. JP_I2S_CB 1-2 short
External MCLK
a. JP_OSC NC and the pin1 is the input for external clock source
b. JP_DGND is the GND for the external clock source
Onboard OSC(12.288MHz)
a. JP_OSC 1-2 short
b. JP_I2S_CB 1-2 NC