Analog Devices EVAL-ADAU1850 User manual

User Guide
EVAL-ADAU1850
Evaluating the ADAU1850 Three ADCs, One DAC, Low Power Codec with Audio/
Fast DSP
Rev. A
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EVALUATION KIT CONTENTS
►EVAL-ADAU1850EBZ evaluation board
►USB cable with mini USB plug
DOCUMENTS NEEDED
►ADAU1850 data sheet
►EVAL-ADAU1850EBZ user guide
GENERAL DESCRIPTION
This user guide explains the design and setup of the EVAL-
ADAU1850EBZ evaluation board.
This evaluation board provides access to all analog and digital
inputs/outputs on the ADAU1850. The ADAU1850 core is controlled
by Analog Devices, Inc., Lark Studio™ software, which interfaces
to the EVAL-ADAU1850EBZ via a USB connection. The software
development kit (SDK) is also provided by Analog Devices for code
development.
The EVAL-ADAU1850EBZ can be powered by the USB bus or by
a single 3.8 V to 5 V supply. These supply options are regulated
to the voltages required on the EVAL-ADAU1850EBZ. The printed
circuit board (PCB) is a 4-layer design, with a ground plane and
a power plane on the inner layers. The EVAL-ADAU1850EBZ
contains connectors for external microphones and speakers. The
master clock can be generated through the internal RC oscillator in
the absence of an external clock source. It also can be provided
externally or by the on-board 24.576 MHz oscillator.
EVAL-ADAU1850EBZ BOARD PHOTOGRAPH
Figure 1.

User Guide EVAL-ADAU1850
TABLE OF CONTENTS
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Evaluation Kit Contents......................................... 1
Documents Needed...............................................1
General Description...............................................1
EVAL-ADAU1850EBZ Board Photograph............. 1
Evaluation Board Block Diagram...........................3
Setting Up the Evaluation Board........................... 4
Installing the Lark Studio Software.....................4
Installing the USB Drivers.................................. 4
Default Switch and Jumper Settings.................. 4
Master Clock Options.........................................4
Setting Up Communication in Software.................5
Powering Up the Board...................................... 5
Connecting the Audio Cables.............................5
Creating a Basic Signal Flow............................. 5
Using the Evaluation Board................................... 8
Power Supply..................................................... 8
Control Port........................................................ 8
Codec System....................................................8
Hardware Description............................................ 9
Jumpers..............................................................9
Evaluation Board Schematic............................... 10
Ordering Information............................................11
Bill of Materials................................................. 11
Notes................................................................12
REVISION HISTORY
10/2022—Rev. 0 to Rev. A
Changes to General Description Section ........................................................................................................1
Changes to Master Clock Options Section ..................................................................................................... 4
Changes to Creating a Basic Flown Section ...................................................................................................5
Changes to Clock Option Section ...................................................................................................................8
7/2021—Revision 0: Initial Version

User Guide EVAL-ADAU1850
EVALUATION BOARD BLOCK DIAGRAM
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Figure 2. EVAL-ADAU1850EBZ Board Block Diagram

User Guide EVAL-ADAU1850
SETTING UP THE EVALUATION BOARD
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INSTALLING THE LARK STUDIO SOFTWARE
Download and install the latest version of Lark Studio by completing
the following steps:
1. Download the installer, and run the executable file.
2. Follow the prompts, including accepting the license agreement,
to install the software.
INSTALLING THE USB DRIVERS
If the USB interface is not recognized by the Lark Studio software
and PC, go to the Future Technology Devices International (FTDI)
Chip official web page and download the relevant drivers.
DEFAULT SWITCH AND JUMPER SETTINGS
The JP3, JP1, JP11, and JP17 jumpers are used to set the
HPVDD_L, AVDD, and IOVDD supplies to the ADAU1850. The
external supply must be connected to P3, P7, P8, or P9.
MASTER CLOCK OPTIONS
The EVAL-ADAU1850EBZ has three options for providing a master
clock to the ADAU1850. The first option is to provide an external
master clock (MCLK) signal directly to the CLKIN pin of the codec.
The second option is to use the on-board 24.576 MHz oscillator.
The third option is to use the internal RC oscillator to generate a
master clock without an external clock source.

User Guide EVAL-ADAU1850
SETTING UP COMMUNICATION IN SOFTWARE
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POWERING UP THE BOARD
To power up the evaluation board, connect the ribbon cable to P1 of
the EVAL-ADAU1850EBZ.
CONNECTING THE AUDIO CABLES
Two channels of the microphone inputs are differential, and one
is single-ended. The headphone output is differential and is dc-cou-
pled. Digital audio signal can be I2S or TDM mode through the
serial audio interface.
CREATING A BASIC SIGNAL FLOW
To create a basic signal flow in LARK Studio, follow these steps:
1. Download Lark Studio from www.analog.com/ADAU1850 to the
desktop.
2. Start Lark Studio by double clicking the shortcut on the desktop.
3. Click New Project from the Project menu, or click Create a
New Project in the Welcome section to create a new project,
as shown in Figure 3. The New Project window shows the
Project Type options.
4. Click the Lark-Lite option for the ADAU1850 and then OK.
5. Edit the file name, and save the file to a user specified location.
6. Click Target Connection in the left navigation panel, and con-
figure the Connection settings pane that opens on the right to
set up the connection. If the USB connects, Target Connected
displays (see Figure 4).
Figure 3. Create a New Project
Figure 4. Connect with EVAL-ADAU1850EBZ

User Guide EVAL-ADAU1850
SETTING UP COMMUNICATION IN SOFTWARE
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Configure the Register Control, FastDSP, and EQ settings on the
left navigation panel. Lark-Lite Register Control has multiple tabs
that control different sections of the ADAU1850. Figure 5 shows
the Power tab, which allows the user to power up or power down
various blocks within the ADAU1850. When a block is powered up,
that block can be configured.
The Clock tab allows the PLL to be used or bypassed. By regis-
ter default, the PLL is enabled but bypassed to save power. To
generate a 24.576 MHz master clock, enable or disable the PLL
according to the provided clock source. On the evaluation board, a
24.576 MHz oscillator is supplied.
To configure an application, follow these steps:
1. Enable POWER_EN, MASTER_BLOCK_EN, and CM_START-
UP_OVER in the CHIP_PWR block in the Power tab by clicking
the OFF button to switch to ON (see Figure 5). When an
on-board 24.576 MHz oscillator is used, ensure MCLKIN_EN is
enabled in the Clock tab.
2. With the default 24.576 MHz oscillator on board, set
PLL_FM_BYPASS to PLL_FM_BP in the Clock tab.
3. Configure the other blocks.
When a register value is changed, click the related Write button in
a block to update a single register, or the Write this Page button
below the tabs to update multiple registers. Click Write All after all
register changes to avoid a configuration error.
Figure 5. Register Configuration

User Guide EVAL-ADAU1850
SETTING UP COMMUNICATION IN SOFTWARE
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If FastDSP is needed in the project, a schematic must be created
with the desired path for the ADAU1850.
1. Click FastDSP in the left navigation panel.
2. In the left pane of the Lark-Lite FastDSP Schematic window,
click an arrow to expand a folder.
3. Select and drag an icon into the schematic window, for exam-
ple, the ADC icon within the IO folder (see Figure 6). In
this example, AIN1 and ASRCI are being routed to FastDSP
Output 0 and Output 1.
4. To download the correct parameter generated from the sche-
matic, set fs to be the same as the FastDSP source,
FDSP_RATE_SOURCE, which is set in the FastDSP tab in
the Lark-Lite Register Control window.
5. Click Download to Target to write the parameter and command
to FastDSP memory. After the download finishes, FastDSP is
enabled and runs automatically.
If the equalizer is needed in the project, a configuration of the filters
must be set for the ADAU1850.
1. Click EQ in the navigation panel.
2. Select the filter numbers and relative filter parameters.
3. Set fs to be same as the equalizer source, EQ_ROUTE, which
is set in the EQ tab in the Lark-Lite Register Control window.
4. Click Download to Target to write the parameter and command
to equalizer memory. After the download finishes, the equalizer
is enabled and runs automatically.
For full details on the operation of Lark-Lite, click Getting Start
Guide from the Help menu of the Lark Studio GUI.
Figure 6. FastDSP Schematic Configuration

User Guide EVAL-ADAU1850
USING THE EVALUATION BOARD
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POWER SUPPLY
Power can be supplied to the EVAL-ADAU1850EBZ in one of three
ways:
►Connecting the USB cable to P1 (see Figure 2)
►Connecting a 3.8 V to 5 V dc power to P3
►Connecting an isolated external power supply to P7 for AVDD,
P8 for IOVDD, and P9 for HPVDD_L
If using a 5 V power supply, the on-board regulator generates the
1.8 V, 3.3 V, and 1.3 V dc supplies. The 1.3 V dc supply from
U1 can be adjusted by changing the values of R29 and R30. For
detailed power supply and jumpers, refer to Table 1. When using
the default SPI communication on board, the IOVDD supply can
only be jumped to 3.3 V.
Table 1. Power Supply Jumper Settings
Source Jumpers Internal External
AVDD_1850 JP1 1.8 V P7
HPVDDL_1850 JP3 1.3 V P9
IOVDD JP17 1.8 V or 3.3 V P8
IOVDD_1850 JP11 from IOVDD JP11 from IOVDD JP11 from IOVDD
CONTROL PORT
The EVAL-ADAU1850EBZ is configured to SPI mode by default.
To operate the codec in I2C or universal asynchronous receiv-
er/transmitter (UART) mode, R10 to R14 are recommended to be
uninstalled. By default, these resistors are connected. For detailed
connection and jumpers on P2 and JP16, refer to Table 2.
Table 2. Control Port Settings
P2 Pin Name
Test
Point
JP16
Pull-Up
JP16
Pull- Down
1 SCL/SCLK TP16 Pin 1 and Pin 2 Pin 2 and Pin 3
3 ADDR1/MOSI/RX TP17 Pin 4 and Pin 5 Pin 5 and Pin 6
5 SDA/MISO/TX TP18 Pin 7 and Pin 8 Pin 8 and Pin 9
7 ADDR0/SS TP19 Pin 10 and Pin 11 Pin 11 and Pin 12
CODEC SYSTEM
Clock Option
The EVAL-ADAU1850EBZ has three options for providing a master
clock to the ADAU1850. The first option is to provide an external
MCLK signal directly to the CLKIN pin of the codec from P16 and
disable the on-board oscillator by placing a jumper on Header JP2.
The second option is to use the on-board 24.576 MHz oscillator.
These two options can be chosen through JP7. The third option is
to use the internal RC oscillator to generate a master clock where
JP2 needs to be jumped to disable the on-board oscillator.
Power-Down
The EVAL-ADAU1850EBZ can power down all analog and digital
circuits of the codec in two ways: pressing the S1 button or placing
a jumper on the JP10 header.
Inputs and Outputs
The EVAL-ADAU1850EBZ has multiple audio input and output
options, including digital and analog. Three analog inputs are con-
figurable as microphone or line inputs. Two of these analog inputs
are differential or single-ended, and one is only single-ended. One
differential output can also be used in headphone or line output
mode.
For microphone signals, the two differential (ADC0 and ADC1)
ADAU1850 analog inputs can be configured as single-ended inputs
with an optional programmable gain amplifier (PGA) mode. But
the ADC2 can only be single-ended with an optional PGA mode.
The headphone output can be set as a line output driver or as a
headphone driver. In line output mode, the typical load is 10 kΩ. In
headphone output mode, the typical load is 16 Ω to 32 Ω.
Serial Audio Interface
Serial audio signals in I2S, left justified, right justified, or time divi-
sion multiplexed (TDM) format are available via the P10 serial audio
interface header to connect an external I2S- or TDM-compatible
device. The IOVDD logic level is 1.8 V or 3.3 V.

User Guide EVAL-ADAU1850
HARDWARE DESCRIPTION
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JUMPERS
Table 3. Connector and Jack Descriptions
Reference
Designator Function Description
P1 USB interface USB 5 V power and communication with Lark Studio
P2 Control port Allow three ways of communication: SPI, I2C, and UART
P3 External 5 V External 5 V source
P4 Analog Input 0 Default differential input 3.5 mm jack
P5 Analog Input 1 Default differential input 3.5 mm jack
P6 Analog Input 2 Single-ended input 3.5 mm jack
P7 External AVDD AVDD power from external source
P8 External IOVDD IOVDD power from external source
P9 External HPVDDL HPVDD_L power from external source
P10 Serial data port Input and output header for serial audio signals
P11 Analog Output Differential output
P12 Analog Input 0 Default differential input pins connection
P13 Analog Input 1 Default differential input pins connection
P14 Analog Input 2 Single ended input pins connection
P15 Analog output Differential output pins connection
P16 External clock Master clock from external source
P17 IRQ/MCLKO pull-up Select IRQ or master clock output pull-up
JP1 Internal/external AVDD select Used to select the external AVDD source or on-board regulator for AVDD
JP2 Disable oscillator Used to disable on-board oscillator
JP3 Internal/external HPVDD_L select Used to select the external HPVDD_L source or on-board regulator for HPVDD_L.
JP7 Internal/external MCLK select Used to select the external source or oscillator
JP10 Power-down Used to enter power-down mode
JP11 IOVDD_1850 Used to provide IOVDD source to the ADAU1850
JP12 IRQ pull-up Used to pull up IRQ pin
JP13 MCLKO pull-up Used to pull up CLKOUT/IRQ pin
JP16 Control port pull-up/down select Used to pull up or pull down control pins (SCL/SCLK, SDA/MISO/TX, ADDR1/
MOSI/RX, and ADDR0/SS)
JP17 Internal/external IOVDD select Used to select the external IOVDD source or on-board regulator for IOVDD

User Guide EVAL-ADAU1850
EVALUATION BOARD SCHEMATIC
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Figure 7. Evaluation Board Schematic