Texas Instruments AMC131M03EVM User manual

EVM User's Guide: AMC131M03EVM
AMC131M03 Evaluation Module
ABSTRACT
This user's guide describes the characteristics, operation, and use of the AMC131M03EVM-PDK. This
evaluation module (EVM) is an evaluation platform for the AMC131M03, which is a 3-channel, simultaneously-
sampling, 24-bit, reinforced isolated delta-sigma (ΔΣ) analog-to-digital converter (ADC) with integrated DC/DC
converter and serial peripheral interface (SPI) interface. The AMC131M03 offers wide dynamic range, low
power, and specific features for energy measurement, making the device an excellent fit for energy metering,
power quality, protection relay, and circuit breaker applications.
The AMC131M03EVM eases the evaluation of the device with hardware, software, and computer connectivity
through the universal serial bus (USB) interface. This user's guide includes complete circuit descriptions,
schematic diagrams, and a bill of materials. Throughout this document, the abbreviation EVM and the term
evaluation module are synonymous with the AMC131M03EVM. The following related documents are available
through the Texas Instruments web site at www.ti.com.
Table 1-1. Related Documentation
Device Literature Number
AMC131M03 SBAS994
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Table of Contents
1 Introduction.............................................................................................................................................................................4
1.1 AMC131M03EVM Kit......................................................................................................................................................... 4
1.2 AMC131M03EVM Board....................................................................................................................................................4
2 EVM Analog Interface.............................................................................................................................................................5
2.1 ADC Analog Input Signal Path........................................................................................................................................... 5
2.2 ADC External Clock (CLKIN) Options................................................................................................................................ 5
3 Digital Interface.......................................................................................................................................................................7
3.1 SPI Communication........................................................................................................................................................... 7
3.2 Connection to the PHI........................................................................................................................................................ 7
3.3 Digital Header.................................................................................................................................................................... 8
4 Power Supplies....................................................................................................................................................................... 9
5 AMC131M03EVM Initial Setup..............................................................................................................................................10
5.1 Default Jumper Settings...................................................................................................................................................10
5.2 EVM Graphical User Interface (GUI) Software Installation...............................................................................................11
6 AMC131M03EVM Operation.................................................................................................................................................13
6.1 EVM GUI Global Settings for ADC Control...................................................................................................................... 14
6.2 Register Map Configuration Tool......................................................................................................................................16
6.3 Time Domain Display Tool................................................................................................................................................17
6.4 Spectral Analysis Tool...................................................................................................................................................... 18
6.5 Histogram Tool................................................................................................................................................................. 19
7 AMC131M03EVM Bill of Materials, PCB Layout, and Schematic..................................................................................... 20
7.1 PCB Layout...................................................................................................................................................................... 20
7.2 Schematics.......................................................................................................................................................................23
7.3 Bill of Materials.................................................................................................................................................................24
List of Figures
Figure 1-1. System Connection for Evaluation............................................................................................................................ 4
Figure 2-1. Analog Input (Schematic).......................................................................................................................................... 5
Figure 2-2. Clock Tree (Schematic)............................................................................................................................................. 6
Figure 5-1. AMC131M03EVM Jumper Default Settings............................................................................................................ 10
Figure 5-2. AMC131M03 Software Installation Prompts............................................................................................................11
Figure 5-3. Device Driver Installation Wizard Prompts.............................................................................................................. 11
Figure 5-4. LabVIEW Run-Time Engine Installation.................................................................................................................. 12
Figure 5-5. AMC131M03EVM GUI Folder Post-Installation...................................................................................................... 12
Figure 6-1. AMC131M03EVM Hardware Setup and LED Indicators......................................................................................... 13
Figure 6-2. Launch the EVM GUI Software............................................................................................................................... 13
Figure 6-3. EVM GUI Global Input Parameters......................................................................................................................... 14
Figure 6-4. Clock Setting Dialog................................................................................................................................................ 15
Figure 6-5. Register Map Configuration.....................................................................................................................................16
Figure 6-6. Time Domain Display Tool Options......................................................................................................................... 17
Figure 6-7. Spectral Analysis Tool............................................................................................................................................. 18
Figure 6-8. Histogram Analysis Tool.......................................................................................................................................... 19
Figure 7-1. Top Silkscreen......................................................................................................................................................... 20
Figure 7-2. Top Layer.................................................................................................................................................................20
Figure 7-3. Ground Layer - Internal........................................................................................................................................... 21
Figure 7-4. Power Layer - Internal............................................................................................................................................. 21
Figure 7-5. Bottom Layer........................................................................................................................................................... 22
Figure 7-6. Bottom Silkscreen................................................................................................................................................... 22
Figure 7-7. AMC131M03EVM Main Schematic......................................................................................................................... 23
List of Tables
Table 1-1. Related Documentation.............................................................................................................................................. 1
Table 2-1. AMC131M03EVM CLKIN Options.............................................................................................................................. 6
Table 3-1. PHI Connector Pin Functions......................................................................................................................................7
Table 3-2. Digital Header Pins..................................................................................................................................................... 8
Table 5-1. Default Settings.........................................................................................................................................................10
Table 7-1. AMC131M03EVM Bill of Materials............................................................................................................................24
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Trademarks
Windows® is a registered trademark of Microsoft.
LabVIEW® is a registered trademark of National Instruments.
All trademarks are the property of their respective owners.
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1 Introduction
The AMC131M03EVM-PDK is a platform for evaluating the performance of the AMC131M03, which is a
3-channel, simultaneously-sampling, 24-bit, reinforced isolated ΔΣ ADC with integrated DC/DC converter. The
evaluation kit includes the AMC131M03EVM board and the precision host interface (PHI) controller board that
enables the accompanying computer software to communicate with the ADC over the USB for data capture and
analysis.
The AMC131M03EVM board includes the AMC131M03 ADC and all the peripheral analog circuits and
components required to extract optimum performance from the ADC.
The PHI board primarily serves three functions:
• Provides a communication interface from the EVM to the computer through a USB port
• Provides the digital input and output signals necessary to communicate with the AMC131M03
• Supplies power to all active circuitry on the AMC131M03EVM board
1.1 AMC131M03EVM Kit
The AMC131M03 evaluation module kit includes the following features:
• Hardware and software required for diagnostic testing as well as accurate performance evaluation of the
AMC131M03 ADC
• USB powered—no external power supply is required
• The PHI controller that provides a convenient communication interface to the AMC131M03 ADC over USB
2.0 (or higher) for power delivery as well as digital input and output
• Easy-to-use evaluation software for 64-bit Microsoft Windows® 7, Windows 8, and Windows 10 operating
systems
• The software suite includes graphical tools for data capture, histogram analysis, and spectral analysis. This
suite also has a provision for exporting data to a text file for post-processing.
Figure 1-1 illustrates an example system setup for evaluation.
PHI Board
A-to-Micro-B
USB Cable
AMC131M03EVM
Included in kit
Signal
Source
AMC131M03
EVM GUI
Figure 1-1. System Connection for Evaluation
1.2 AMC131M03EVM Board
The AMC131M03EVM board includes the following features:
• External signal source from differential pair headers
• Options to use external digital power supply
• Serial interface header for easy connection to the PHI controller
• Pin connections to monitor digital signals with a logic analyzer
• Onboard 8.192-MHz crystal oscillator, or external clock from PHI controller card
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2 EVM Analog Interface
The AMC131M03EVM is designed for easy interfacing with analog sources. This section covers the details of
the front-end circuit including jumper configuration for different input test signals and board connectors for signal
sources.
2.1 ADC Analog Input Signal Path
Analog inputs to the EVM can be connected to either the terminal blocks or to the header pins associated with
each ADC channel. The headers for each channel allow the user to configure the inputs differentially depending
on the signal to be measured. The screw terminal blocks can interface directly with the leads of an external
sensor input. Figure 2-1 shows the signal chain used for all three input channels on the EVM .
49.9
R3
49.9
R4
Analog Inputs
HGND
HGND
HLDO_IN
DCDC_OUT
ADC
AIN0N
10 AIN0P
9
AIN1P
8
AIN2P/GPO
6
AIN12N
7
DCDC_HGND
2
DCDC_OUT
1
HGND
5
HLDO_IN
3
HLDO_OUT
4
DRDY
SYNC/RESET
CLKIN
DCDC_CAP
DGND
DIN
DOUT
DVDD
SCLK
AMC131M03DFM
U1
HLDO_OUT
49.9
R9
HGND
49.9
R10
4700pF
C9
4700pF
C8
100pF
C2
100pF
C3
100pF
C5
100pF
C12
1
2
J1
AIN2
HGND
DCDC_HGND
HGND
1 2
3 4
JP3
1
2
J3
AIN0
1
2
J2
AIN1
1 2
3 4
JP2
HGND
1.00k
R7
DNP
0
R8
0
R1
1.00k
R2
DNP
HGND
100pF
C1
1
2
3
JP1
HLDO_OUT
100k
R6 49.9
R5
4700pF
C7
TP1
GPO
TMP6331DYAT
RT1
HGND
Figure 2-1. Analog Input (Schematic)
There are 3 analog input channels for the AMC131M03EVM: channel 0, 1, and 2. Signals can be applied to
these channels via terminal blocks J3, J2, and J1, respectively.
Channel 0 (AIN0) and Channel 1 (AIN1) contain the same circuitry. This includes a terminal block to apply
signals to AIN0P/N and AIN1P/N. These inputs can also be shorted to HGND via the provided jumpers on
JP2 and JP3, respectively. Each channel also contains both common-mode and differential passive filters for
antialiasing. If needed, one input on each channel can be divided down using the provided resistor divider
footprints (this is unpopulated by default).
Channel 2 (AIN2) shares a negative channel input with Channel 1 (AIN12N). An external voltage can be applied
to AIN2P by connecting to the terminal block, J1. This signal measured against AIN12N by configuring JP1 in the
[1-2] position.
Another common use of Channel 2 is to measure the output of an external temperature sensor. The
AMC131M03EVM provides an example temperature sensor circuit using the TMP6331, a 100-kΩ linear
thermistor. The temperature sensor output can be selected using the [2-3] position on JP1.
2.2 ADC External Clock (CLKIN) Options
The AMC131M03 requires a continuous, free-running external controller clock at the CLKIN pin for normal
operation. The onboard complementary metal oxide semiconductor (CMOS) crystal oscillator (Y1) provides the
nominal 8.192-MHz clock frequency used in the high-resolution (HR) mode of the device. A D flip-flops (U3)
divide the Y1 clock output to produce clock frequencies of 4.096 MHz to support the low-power (LP) mode.
Install a jumper in the appropriate position on the JP4 header to provide four selectable clock frequency
options. An external clock frequency can also be provided to any odd-numbered pin on JP4 when the jumper is
uninstalled. TI also recommends powering down Y1 by installing JP6 when providing an external clock. When
using an external clock, ground must be shared between the external clock source and the EVM ground. The
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external clock must adhere to the frequency and amplitude limits outlined in the AMC131M03 data sheet. Table
2-1 lists the JP4 jumper settings for the clock input selections.
Clock Tree
Q
4 D 1
CLK 2
GND
3 VCC 5
SN74AUP1G80DCKR
U3
OSC_8.192MHz
DGND
DGND
100k
R24
JP6
OSC_EN
OSC_4.096MHz
VDD 4
OE 1
GND
2
CLOCK OUT
3
Y1
8.192MHz
ADC_DIGITAL.CLKIN
DGND
DGND
0.1uF
C19
ADC_DVDD
ADC_DVDD
PHI_DIGITAL.OSC_EN
ADC_DVDD
0.1uF
C21
DGND
33.0
R11
1 2
3 4
5 6
JP4
CLKSEL
PHI_DIGITAL.CLKIN
33.0
R12
33.0R13 PHI_DIGITAL.MCLK_OUT
Figure 2-2. Clock Tree (Schematic)
Table 2-1. AMC131M03EVM CLKIN Options
JP4 Setting CLKIN Source CLKIN Frequency
1-2 Y1 8.192 MHz
3-4 U3 4.096 MHz
5-6 PHI Configured in graphical user interface (GUI)
Open External clock to JP4[5] See data sheet for CLKIN range
Note
The current build of the GUI does not support the CLKIN signal generated by the PHI.
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3 Digital Interface
As noted in Section 1, the EVM interfaces with the PHI and communicates with the computer over the USB.
There are two devices on the EVM with which the PHI communicates: the AMC131M03 ADC (over SPI) and
the EEPROM (over I2C). The EEPROM comes pre-programmed with the information required to configure and
initialize the AMC131M03EVM platform. When the hardware is initialized, the EEPROM is no longer used.
3.1 SPI Communication
The AMC131M03EVM supports limited interface modes as detailed in the AMC131M03 data sheet. The
AMC131M03 uses a SPI-compatible interface to configure the device and retrieve conversion data. SPI
communication on the AMC131M03 is performed in frames. Each SPI communication frame consists of several
words. The word size is configurable as either 16 bits, 24 bits (default), or 32 bits by programming the
WLENGTH[1:0] bits in the MODE register.
Additionally, the DRDY pin indicates when conversion data are available to be read by the controller. The
DRDY_SEL[1:0] bits, DRDY_HIZ bit, and the DRDY_FMT bit in the MODE register control the behavior of the
DRDY pin.
For this EVM, not all modes and functions for this SPI communication are supported. Functions not supported
are disabled in the EVM GUI software. For more information about the SPI communication, see the AMC131M03
data sheet.
3.2 Connection to the PHI
The AMC131M03EVM board communicates with the PHI through a shrouded, 60-pin connector, J6. There are
two round standoffs next to J6 with Phillips-head screws. To connect the PHI to the EVM, remove the screws,
attach the PHI to the EVM, and replace the screws into the standoffs. The screws secure the EVM to the PHI
and verifies the connection between the boards.
Table 3-1 lists the different PHI connection and their functions.
Table 3-1. PHI Connector Pin Functions
PHI Connector Pin Name PHI Connector Pin Function
DGND J6[3] Ground
OSC_EN J6[6] External oscilator enable
DIN J6[18] Serial data input for the AMC131M03
CS J6[22] Chip select for the AMC131M03; active low
SCLK J6[24] Serial data clock for the AMC131M03
CAPCLK J6[26] Capture clock for the AMC131M03
CAPCLK J6[28] Capture clock for the AMC131M03
DRDY J6[30] Data ready for the AMC131M03; active low
OSC_8.192MHz J6[32] Controller clock input for the AMC131M03
MCLK_OUT J6[34] Controller
clock output for the AMC131M03
DOUT J6[36] Serial data output for the AMC131M03
SYNC/ RESET J6[46] Conversion synchronization or system reset for the AMC131M03;
active low
EVM_WP J6[49] Write protection enable for the EEPROM
ADC_DVDD J6[50] Power-supply source for the AMC131M03
SDA J6[56] I2C serial data for the EEPROM used to identify the EVM
SCL J6[58] I2C serial clock for the EEPROM used to identify the EVM
EVM_ID_PWR J6[59] Power-supply source for the EEPROM used to identify the EVM
DGND J6[60] Ground
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3.3 Digital Header
In addition to the PHI, the EVM has a header connected to the digital lines that can be used to connect a logic
analyzer or oscilloscope. This placement allows for easy access to the digital communications. Header J5 is
connected to the digital lines between the AMC131M03 and the PHI connector. Table 3-2 describes the digital
header pins.
Table 3-2. Digital Header Pins
AMC131M03 Pin Name Digital Header Pin
DIN J5[1], J5[2]
CS J5[3], J5[4]
SCLK J5[5], J5[6]
DRDY J5[7], J5[8]
DOUT J5[9], J5[10]
SYNC/ RESET J5[11], J5[12]
DGND J5[13], J5[14]
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4 Power Supplies
The PHI provides multiple power-supply options for the EVM, derived from the USB supply of the computer.
The EEPROM on the AMC131M03EVM uses a 3.3-V power supply generated directly by the PHI. The low-side
analog and digital supply (DVDD) of the ADC uses a 3.3-V power supply provided directly by a low-dropout
(LDO) regulator on the PHI.
The power supply for each active component on the EVM is bypassed with a ceramic capacitor placed close
to that component. Additionally, the EVM layout uses thick traces or large copper fill areas, where possible,
between bypass capacitors and their loads to minimize inductance along the load current path.
As mentioned previously in Section 1, power to the EVM is supplied by the PHI through connector J6. For
information about PHI pins and the power connections, see Table 3-1.
With modifications, the user can use external supplies for the low-side analog and digital supply (DVDD) of the
ADC. DVDD can be driven externally from the terminal block J4.
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5 AMC131M03EVM Initial Setup
This section explains the initial hardware and software setup procedure that must be completed for properly
operating the AMC131M03EVM.
5.1 Default Jumper Settings
After unpacking, the EVM is already configured with the default jumper settings. Figure 5-1 shows the locations
for the default jumpers.
Figure 5-1. AMC131M03EVM Jumper Default Settings
The default position of the JP4 jumper is across [1-2] at the top. JP4 sets the onboard oscillator frequency to
8.192 MHz, used for the AMC131M03 in high-resolution mode. The default connection for JP1 is to the left [1-2],
so that the channel AIN2P of the AMC131M03 is used to convert the signal from the J1 terminal block.
The default settings, as listed in Table 5-1, includes no jumpers installed at JP5, JP6. When installed, JP5
enables the EEPROM for write, and JP6 disables the onboard oscillator.
Table 5-1. Default Settings
Jumper Position Function
JP1 [1-2] Selects input for AIN2P of the ADC
JP2 Not installed Ground connection for input
JP3 Not installed Ground connection for input
JP4 [1-2] Oscillator frequency select, 8.192MHz
JP5 Not installed Disables write for EEPROM
JP6 Not installed Disables on-board oscillator
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5.2 EVM Graphical User Interface (GUI) Software Installation
Download the latest version of the EVM GUI installer from the Tools and Software folder of the
AMC131M03EVM and run the GUI installer to install the EVM GUI software on your computer.
CAUTION
Manually disable any antivirus software running on the computer before downloading the EVM GUI
installer onto the local hard disk. Depending on the antivirus settings, an error message can appear
or the installer. The .exe file can be deleted.
Accept the license agreements and follow the on-screen instructions shown in Figure 5-2 to complete the
installation.
Figure 5-2. AMC131M03 Software Installation Prompts
As a part of the AMC131M03EVM GUI installation, a prompt with a Device Driver Installation (as shown in Figure
5-3) appears on the screen. Click Next to proceed.
Figure 5-3. Device Driver Installation Wizard Prompts
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Note
A notice can appear on the screen stating that Windows cannot verify the publisher of this driver
software. Select Install this driver software anyway.
The AMC131M03EVM requires the LabVIEW® run-time engine and can prompt for the installation of this
software, as shown in Figure 5-4, if not already installed.
Figure 5-4. LabVIEW Run-Time Engine Installation
Verify that C:\Program Files (x86)\Texas Instruments\AMC131M03EVM is as shown in Figure 5-5 after these
installations.
Figure 5-5. AMC131M03EVM GUI Folder Post-Installation
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6 AMC131M03EVM Operation
The following instructions are a step-by-step guide to connecting the AMC131M03EVM to the computer and
evaluating the performance of the AMC131M03:
1. Connect the AMC131M03EVM to the PHI. Install the two screws as indicated in Figure 6-1.
2. Use the provided USB cable to connect the PHI to the computer.
• LED D5 on the PHI lights up, indicating that the PHI is powered up
• LEDs D1 and D2 on the PHI start blinking to indicate that the PHI is booted up and communicating with
the PC; Figure 6-1 shows the resulting LED indicators
Figure 6-1. AMC131M03EVM Hardware Setup and LED Indicators
3. Figure 6-2 shows how to launch the AMC131M03EVM GUI software.
Figure 6-2. Launch the EVM GUI Software
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6.1 EVM GUI Global Settings for ADC Control
Although the EVM GUI does not allow direct access to the levels and timing configuration of the ADC digital
interface, the EVM GUI does give users high-level control over virtually all functions of the AMC131M03
including interface modes, sampling rate, and number of samples to be captured. Figure 6-3 identifies the input
parameters of the GUI (as well as their default values) through which the various functions of the AMC131M03
can be exercised.
Figure 6-3. EVM GUI Global Input Parameters
There are four pages available in the AMC131M03EVM GUI. The information area displays the results of each
of the pages. Each of these pages display a different control or measurement of the device. The Register Map
Config page is used to read and write to the registers of the device. The Time Domain Display page is used to
collect a set of data from the device and display the result. The Spectral Analysis page can determine the FFT of
the collected data, and the Histogram Analysis page shows a histogram of the collected data and displays basic
statistics of the result.
The Single Commands section allows for direct control of the device for five basic functions. First the Reset
Device button sends a signal to the SYNC/RESET pin to reset the device. The Standby button puts the device
into a low-power state in which all channels are disabled, and the reference and other non-essential circuitry are
powered down. The Wake up button wakes the device from standby to convert mode. The Lock button lock the
interface such that only the NULL, UNLOCK, and RREG commands are valid. The Unlock button unlocks the
interface.
The Interface Configuration options in this pane allows the user to choose from different frame word sizes
available on the AMC131M03. This section also sets the data rate by setting the oversampling ratio (OSR) in
the ADC. Finally, this section can be used to set the power modes in the registers. The AMC131M03 can be
set to high-resolution and low power modes in conjunction with the jumper settings of JP4 for the CLKIN pin, as
outlined in Table 2-1. This information is also discussed in Section 2.2.
The Clock and Data Rate section allows the user to select the CLK source and SCLK source, and change the
SCLK frequency (in Hz). These configurations can be implemented by checking the clock setting button in the
CLK Frequency area and changing the dropdown as shown in Figure 6-4 . The clock source selection in the
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Clock Settings must match the jumper installed on JP4 on the AMC131M03EVM. Select Custom if an external
CLKIN clock is provided directly to JP4[5].
Figure 6-4. Clock Setting Dialog
The GUI tries to match this frequency as closely as possible by changing the PHI PLL settings, but the
achievable frequency can differ from the target value entered. This section also displays the data rate of the
ADC as controlled by the OSR configuration.
The GUI is switched between hardware mode and simulation mode by checking and unchecking the Connected
to Hardware box in the top right area of the screen at any time.
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6.2 Register Map Configuration Tool
The register map configuration tool allows the user to view and modify the registers of the AMC131M03. This
tool can be selected, as indicated in Figure 6-5, by clicking on the Register Map Config button at the Pages
section of the left pane. On power-up, the values on this page correspond to the ADC default register settings
with the DC/DC converter enabled. The register values can be edited by:
1. Double-clicking the corresponding Value field and entering the desired hexadecimal register setting.
2. Choosing the desired setting for each bit field in the Field View below the register map.
3. Clicking each individual bit to toggle the current value.
Each of the three actions above immediately executes a WREG (“register-write”) command followed by a RREG
(“register-read”) command to confirm the register setting was written correctly.
If interface mode settings are affected by the change in register values, then this change reflects on the left
pane immediately. The changes in the register value reflect on the AMC131M03 device on the AMC131M03EVM
based on the Update Mode selection, as described in Section 6.1.
Figure 6-5. Register Map Configuration
Section 6.3 through Section 6.5 describe the data collection and analysis features of the AMC131M03EVM GUI.
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6.3 Time Domain Display Tool
The time domain display tool allows visualization of the ADC response to a given input signal. This tool is useful
for both studying the behavior and debugging any gross problems with the ADC or drive circuits.
The user can trigger a capture of the data of the selected number of samples from the AMC131M03EVM, as per
the current interface mode settings indicated in Figure 6-6 by using the Capture button. The sample indices are
on the x-axis and the y-axes showing the corresponding output codes or the equivalent analog voltages based
on the specified reference voltage. The code or voltage unit can be selected in the botom right Unit area at any
time. Switching pages to any of the Analysis tools described in the subsequent sections causes calculations to
be performed on the same set of data.
Figure 6-6. Time Domain Display Tool Options
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6.4 Spectral Analysis Tool
The spectral analysis tool, shown in Figure 6-7, is intended to evaluate the dynamic performance (SNR, THD,
SFDR, SINAD, and ENOB) of the AMC131M03 ADC through single-tone sinusoidal signal FFT analysis using
the 7-term Blackman-Harris window setting.
Figure 6-7. Spectral Analysis Tool
The FFT tool includes windowing options that are required to mitigate the effects of non-coherent sampling (this
discussion is beyond the scope of this document). The 7-Term Blackman Harris window is the default option
and has sufficient dynamic range to resolve the frequency components up to a 24-bit ADC. The None option
corresponds to not using a window (or using a rectangular window) and is not recommended.
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6.5 Histogram Tool
Noise degrades ADC resolution and the histogram tool can be used to estimate effective resolution, which is an
indicator of the number of bits of ADC resolution losses resulting from noise generated by the various sources
connected to the ADC when measuring a DC signal. The cumulative effect of noise coupling to the ADC output
from sources, such as the input drive circuits, the reference drive circuit, the ADC power supply, and the ADC
itself is reflected in the standard deviation of the ADC output code histogram that is obtained by performing
multiple conversions of a DC input applied to a given channel.
As shown in Figure 6-8, the histogram corresponding to a DC input is displayed on clicking the Capture button.
Figure 6-8. Histogram Analysis Tool
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7 AMC131M03EVM Bill of Materials, PCB Layout, and Schematic
7.1 PCB Layout
Figure 7-1 through Figure 7-6 illustrate the AMC131M03EVM PCB layout.
Figure 7-1. Top Silkscreen
Figure 7-2. Top Layer
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