Texas Instruments INA229 User manual

User’s Guide
INA228, INA229, INA237, INA238, and INA239 EVM User’s
Guide
Mitch Morse
ABSTRACT
This user’s guide describes the characteristics, operation, and use of the INA228, INA229, INA237, INA238, and
INA239 evaluation modules (EVMs). These EVMs are designed to evaluate the performance of the INA228,
INA229, INA237, INA238, and INA239. Throughout this document, the terms evaluation board, evaluation
module, and EVM are synonymous with the INA228EVM, INA229EVM, INA237EVM, INA238EVM, and
INA239EVM. This document includes a schematic, reference printed-circuit board (PCB) layouts, and a
complete bill of materials (BOM).
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Table of Contents
1 Trademarks..............................................................................................................................................................................2
2 General Texas Instruments High Voltage Evaluation (TI HV EVM) User Safety Guidelines............................................ 3
3 Overview..................................................................................................................................................................................5
3.1 Kit Contents........................................................................................................................................................................5
3.2 Related Documentation From Texas Instruments.............................................................................................................. 6
4 Hardware................................................................................................................................................................................. 6
4.1 Features............................................................................................................................................................................. 6
5 Operation.................................................................................................................................................................................7
5.1 Quick Start Setup............................................................................................................................................................... 7
5.2 EVM Operation...................................................................................................................................................................7
6 Circuitry................................................................................................................................................................................. 18
6.1 Current Sensing IC...........................................................................................................................................................18
6.2 Input Signal Path..............................................................................................................................................................18
6.3 Digital Circuitry................................................................................................................................................................. 18
7 Schematics, PCB Layout, and Bill of Materials................................................................................................................. 19
7.1 Schematics.......................................................................................................................................................................19
7.2 PCB Layout...................................................................................................................................................................... 23
7.3 Bill of Materials.................................................................................................................................................................25
8 Revision History................................................................................................................................................................... 28
1 Trademarks
All trademarks are the property of their respective owners.
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2 General Texas Instruments High Voltage Evaluation (TI HV EVM) User Safety
Guidelines
WARNING
Always follow TI’s setup and application instructions, including use of all interface components within their
recommended electrical rated voltage and power limits. Always use electrical safety precautions to help ensure
your personal safety and those working around you. Contact TI's Product Information Center http://
support/ti./com for further information.
Save all warnings and instructions for future reference.
WARNING
Failure to follow warnings and instructions may result in personal injury, property damage or death
due to electrical shock and burn hazards.
The term TI HV EVM refers to an electronic device typically provided as an open-framed, unenclosed printed-
circuit board assembly. It is intended strictly for use in development laboratory environments, solely for qualified
professional users having training, expertise, and knowledge of electrical safety risks in development and
application of high-voltage electrical circuits. Any other use and/or application are strictly prohibited by Texas
Instruments. If you are not suitable-qualified, you should immediately stop from further use of the HV EVM.
1. Work Area Safety
a. Keep work area clean and orderly.
b. Qualified observer(s) must be present anytime circuits are energized.
c. Effective barriers and signage must be present in the area where the TI HV EVM and its interface
electronics are energized, indicating operation of accessible high voltages may be present, for the
purpose of protecting inadvertent access.
d. All interface circuits, power supplies, evaluation modules, instruments, meters, scopes and other related
apparatus used in a development environment exceeding 50Vrms/75VDC must be electrically located
within a protected Emergency Power Off EPO protected power strip.
e. Use stable and nonconductive work surface.
f. Use adequately insulated clamps and wires to attach measurement probes and instruments. No freehand
testing whenever possible.
2. Electrical Safety
As a precautionary measure, it is always a good engineering practice to assume that the entire EVM may
have fully accessible and active high voltages.
a. De-energize the TI HV EVM and all its inputs, outputs, and electrical loads before performing any
electrical or other diagnostic measurements. Revalidate that TI HV EVM power has been safely de-
energized.
b. With the EVM confirmed de-energized, proceed with required electrical circuit configurations, wiring,
measurement equipment connection, and other application needs, while still assuming the EVM circuit
and measuring instruments are electrically live.
c. After EVM readiness is complete, energize the EVM as intended.
WARNING
While the EVM is energized, never touch the EVM or its electrical circuits, as they could be at
high voltages capable of causing electrical shock hazard.
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3. Personal Safety
a. Wear personal protective equipment (for example, latex gloves or safety glasses with side shields) or
protect the EVM in an adequate lucent plastic box with interlocks to protect from accidental touch.
Limitation for safe use:
EVMs are not to be used as all or part of a production unit.
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3 Overview
The INA228, INA229, INA237, INA238, and INA239 devices are digital power monitors with integrated 20-bit
(INA229 and INA228) and 16-bit (INA237, INA238, and INA239) delta-sigma ADCs specifically designed for
current-sensing applications. The devices can measure a selectable full-scale differential input of ±163.84 mV or
±40.96 mV across the shunt with common-mode voltage support from –0.3 V to +85 V. For the INA228 and
INA229, built-in digital accumulation calculates average power, internal die temperature, energy, and charge
accumulation. For the INA237, INA238, and INA239, built-in digital accumulation calculates average power and
internal die temperature. All devices also have built-in diagnostics to indicate system health accessible through a
digital output pin, ALERT. The devices operate from a single supply of 2.7 V to 5.5 V, drawing < 1.1-mA current
during operation and with < 5-µA current during shutdown. The output can be interfaced with a multitude of
microcontrollers (MCUs) with a standard 4-wire SPI interface (INA229 and INA239) or with a standard I2C
interface (INA228, INA237, and INA238).
Table 3-1. Device Summary
PRODUCT
DIGITAL
PROTOCOL
ADC
RESOLUTION
MAX GAIN
ERROR
MAX OFFSET
VOLTAGE
INA228 I2C 20-bit 0.05% ±1 µV
INA229 SPI 20-bit 0.05% ±1 µV
INA237 I2C 16-bit 0.3% ±50 µV
INA238 I2C 16-bit 0.1% ±5 µV
INA239 SPI 16-bit 0.1% ±5 µV
3.1 Kit Contents
Table 3-2 lists the contents of the EVM kit. Contact the nearest Texas Instruments Product Information Center if
any component is missing.
Table 3-2. Kit Contents
ITEM QUANTITY
INA228EVM, INA229EVM, INA237EVM,
INA238EVM, OR INA239EVM test board
1
Sensor Control Board (SCB) 1
USB cable 1
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3.2 Related Documentation From Texas Instruments
This user's guide is available from the TI website under literature number SBOU241. Any letter appended to the
literature number corresponds to the document revision that is current at the time of the writing of this document.
Newer revisions are available from www.ti.com or the Texas Instruments' Literature Response Center at (800)
477-8924 or the Product Information Center at [phone]. When ordering, identify the document by both
title and literature number. Table 3-3 lists documentation related to the EVM. Click the links in Table 3-3 for
further information. The device name links to the product web folder on www.ti.com. The literature number links
to the document PDF.
Table 3-3. Related Documentation
DOCUMENT TITLE
DOCUMENT LITERATURE
NUMBER
INA228-Q1 data sheet SLYS022
INA229-Q1 data sheet SLYS024
INA237-Q1 data sheet SBOSA27
INA238-Q1 data sheet SLYS026
INA239-Q1 data sheet SLYS028
4 Hardware
The EVM is an easy-to-use platform for evaluating the main features and performance of the INA228, INA229,
INA237, INA238, or INA239. The EVM supports current measurements up to 10 amps, and includes a graphical
user interface (GUI) used to read and write device registers as well as view and save results data.
The EVM is intended to provide basic functional evaluation of the devices. The layout is not intended to be a
model for the target circuit, nor is it laid out for electromagnetic compatibility (EMC) testing. The EVM consists of
two printed-circuit boards (PCBs). The larger PCB is referred to as the EVM, and has either the INA228, INA229,
INA237, INA238, or INA239 installed. The smaller PCB is referred to as the SCB Controller, and is used to
interface the EVM with the GUI.
4.1 Features
• GUI support to read and write device registers as well as view and save results data
• Detachable EVM for custom use cases
• Conveniently powered from a common micro-USB connector
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5 Operation
5.1 Quick Start Setup
The following instructions describe how to set up and use the EVM.
1. Download this driver and install it as an administrator: https://www.ti.com/lit/zip/sbac253.
2. Attach the EVM to the SCB Controller as shown in Figure 5-1.
a. Refer to Figure 5-2 when connecting multiple EVMs of the same type together.
3. Connect the EVM to a PC using the provided USB cable.
a. Insert the micro USB cable into the SCB Controller onboard USB receptacle J2.
b. Plug the other end of the USB cable into a PC.
4. Access the GUI from this link in either Chrome or Firefox: https://dev.ti.com/gallery/info/4910879/
INA228_229_237_238_239EVM_GUI/.
5. Connect the GND reference of the external system to the GND node of the EVM (pin 1 of J1).
6. Provide a differential input voltage signal to the IN+ and IN– nodes by connecting the signal leads to J1 pin 5
or 6 and J1 pin 3 or 4 on the EVM as explained in Section 5.2.2.
5.2 EVM Operation
To use the EVM with the included SCB Controller, connect the EVM as shown in Figure 5-1.
Figure 5-1. EVM Connected to SCB Controller
If using multiple EVMs, connect them as shown in Figure 5-2. Make sure to use a different chip select/address
for each device. The GUI only supports one EVM/device type at a time.
Figure 5-2. Multiple EVMs Connected to SCB Controller
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5.2.1 Setup
5.2.1.1 Driver Installation
Download and install this driver: https://www.ti.com/lit/zip/sbac253. This is a one-time step per computer. Unzip
the folder and run the .exe file with administrator privileges.
5.2.1.2 Firmware
The firmware comes preinstalled on the SCB Controller. Firmware updates will be pushed through the GUI
(requires previous driver to be installed). Downloaded offline GUIs will only update the SCB Controller with the
latest firmware available at the time of download. To check for the latest GUI or Firmware updates, launch the
GUI from the web browser.
5.2.1.2.1 Firmware Debug
If the firmware gets corrupted or must be manually reinstalled for any reason, follow these steps to reinstall the
firmware.
1. First, see if the GUI can program the firmware manually.
a. Plug in the SCB controller to the PC
b. Launch the GUI
c. It is possible that the MCU has already entered DFU mode. If so, the GUI may notify you and try to update
the firmware to the latest version.
d. If it does not update automatically, go to File > Program Device...
2. If that does not work (or if the "Program Device" button is grayed out), manually configure the MCU on the
SCB Controller to be in Device Firmware Update (DFU) Mode. This can be done through either of the below
methods with the SCB Controller powered on:
a. Through software:
• Send the command 'bsl' on the SCB's USB Serial (COM) port.
b. Though hardware:
• Short the two test points labeled "DFU" (shown in Figure 5-3) with a pair of tweezers (or wire) while
pressing the RESET button.
Figure 5-3. Test Points Used to Enter DFU Mode Manually
• If the PAMB board is being used instead, these test points are located near PK1 and PK2.
With the MCU in DFU mode, the firmware can now be uploaded through the method outlined in Step 1.
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5.2.1.3 GUI Setup and Usage
The GUI can be accessed from this link in either Chrome or Firefox: https://dev.ti.com/gallery/info/4910879/
INA228_229_237_238_239EVM_GUI/.
5.2.1.3.1 Initial Setup
To set up the GUI the first time:
1. Make sure that the previously mentioned driver was installed successfully to ensure that everything works
properly and that the GUI can update the EVM firmware, if necessary.
2. With the EVM/SCB Controller unit plugged into the PC, go to the previously-provided GUI link.
3. To launch the GUI from the web browser, click the GUI Composer application shown in Figure 5-4.
Figure 5-4. GUI Composer Application
a. For first-time GUI Composer setup, follow the prompts to download the TI Cloud Agent and browser
extension shown in Figure 5-5. These prompts will appear after you close the README.md dialog.
Figure 5-5. TI Cloud Agent
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4. Optionally, the GUI can be downloaded for offline use by clicking the icon in the GUI Composer application
(shown in Figure 5-4) and following the prompts.
5.2.1.3.2 GUI Operation
To operate the GUI, follow these steps:
1. Connect to and launch the GUI as described in Section 5.2.1.3.1.
2. With the EVM connected to the GUI, close the README.md file page to initiate the connection. If successful,
"Hardware Connected" should be visible near the bottom left corner of the GUI as in Figure 5-6.
Figure 5-6. Hardware Connected
a. A green indicator with the device type and the text "DEVICE CONNECTED" should also be visible near
the top left of the GUI, as shown in Figure 5-7.
Figure 5-7. Device Connected
b. If "Hardware Connected" and "DEVICE CONNECTED" do not show in the GUI, check different hardware
COM ports under Options >> Serial Port, as shown in Figure 5-8.
Figure 5-8. Change Serial Port
c. If the hardware still does not connect, make sure you are using the correct GUI/EVM combination.
i. If you are using the correct GUI/EVM combination, you may need to reprogram the firmware of the
SCB, as described in Firmware Debug.
3. To view and edit the device register map, click the (registers) icon on the menu on the left.
a. From this page, you can read and write register settings on the EVM. For questions about a register or
register bit field, select the icon. For more questions about registers, check the data sheet.
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4. To view and collect results data over time, go to the plots page by clicking the (plots) icon on the menu on
the left. The plots page will look similar the one shown in Figure 5-9, depending on the connected device.
Figure 5-9. GUI Plots Page
a. Below is a description of how to use the buttons and settings at the top of the plots page and next to each
plot:
i. Use the "Results to collect/show" box on the left to select which register values to collect data for. If a
results register is unselected, then the plot below will not show the data and the EVM will not try to
read this value during the collect cycle. If you disable one of these settings while the EVM is collecting
data, then the plot will not show, but data will still be collected and the plot will update in the
background.
ii. Set the "Number of EVMs" drop-down menu to the number of EVMs currently in use. See Figure 5-2 to
see how to attach multiple EVMs together. Use the onboard switch(es) to select a different address for
each EVM. The GUI only supports one EVM/device type at a time.
1. Set the switch settings for each connected EVM. "EVM 1" will automatically populate with the lowest
addressed device unless a setting has already been selected.
2. Use the "LINK TO REGMAP" button to set the regmap of the desired EVM. Use this button to
change settings for each connected device through the register map. Functionally, this button sets
the default read/write address in the MCU and then reads all register values back to update the
register map. Note that if data is being collected at a high frequency, then this may cause a minor
delay in the collection data. For optimal performance, set device settings before you start collecting
data.
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iii. Use the "COLLECT DATA" button to start data collection.
1. In this mode, the MCU reads and sends the selected result values for each device over a USB
BULK channel. All results from one device are read before moving on to the next device. All result
values from all EVMs together are considered one "sample set".
2. When the "Delay between samples" is used, that is the delay between the start of each sample set.
A delay of "0" corresponds to "as fast as possible". If the delay used is shorter than the amount of
time it takes to read all results from all EVMs, the setting would be the same as a delay of "0". Note,
the registers are read when the firmware is ready to read them, optionally based on the delay timer.
It does not take into account conversion time or averaging. Although you can read and write to
other registers through the register map page while collecting data, it is possible that this adds a
delay to the data being collected.
3. Use the "CLEAR ALL PLOTS" button to clear the data from all plots together. This can be done
individually for each plot. Similarly, you can use the "#Samples all:" box to change the number of
samples shown in each plot. This can also be done individually per plot.
4. Use the "SAVE PLOT" button next to each plot to save the data in a spreadsheet.
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5.2.2 Current Sensing Operation
The EVM allows the user to either emulate the voltage developed across a sense resistor based on a given set
of system conditions by applying a differential voltage across the IN+ and IN– terminals directly, or to connect the
device inputs to an external shunt. Optionally, a 2512 surface-mount technology (SMT) shunt resistor can be
soldered across the pads of R1, and these inputs can be connected in series with the external system and load
current. There are two terminals each for IN+ (J1 pins 5 and 6) and IN– (J1 pins 3 and 4) for convenience.
5.2.2.1 Without Shunt Resistor
To configure a measurement evaluation without a shunt resistor, follow these steps:
1. Connect a differential voltage across the IN+ and IN– terminals as shown in Figure 5-10.
a. If the differential voltage supply is a floating supply, connect a –0.3-V to 85-V common-mode voltage
(leave powered off until finished setting up) to the inputs by connecting the positive lead of the external
voltage source to either the IN+ or IN– terminal. This action effectively raises the absolute common-mode
voltage of the input pins. Make sure that the differential voltage plus or minus the common-mode voltage
does not go out of the –0.3-V to 85-V range.
Figure 5-10. IN+ and IN– Wiring Without a Shunt Resistor
2. Connect the VBUS terminal (J1 pin 2) to the desired bus voltage (likely either IN+ or IN–).
3. Connect the source ground to the GND terminal (J1 pin 1).
4. Power on the system, and observe the device states and outputs through the GUI.
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5.2.2.2 With Shunt Resistor
To configure a measurement evaluation with a shunt resistor, follow these steps:
1. Connect a shunt resister by doing either of the following:
a. Solder a 2512 resistor across the pads of R1 that connects the IN+ and IN– inputs.
b. Connect an external shunt across the IN+ and IN– terminals of J1, preferably across pins 4 and 5, as
shown in Figure 5-11.
i. If an external shunt is being used, make the connections such that the sensing location is across the
shunt and there will be no high current on the sensing path. See the TI Precision Labs - Current Sense
Amplifiers: Shunt Resistor Layout video for more information.
2. Connect the IN+ and IN– terminals in series with the load while powered off.
Figure 5-11. IN+ and IN– Wiring With a Shunt Resistor
WARNING
If measuring current, first make sure that the equipment (shunt resistor, wires, connectors, and so
on) can support the amperage and power dissipation. Secondly, make sure that the current
flowing through J1 does not exceed 10 A. Failure to do so can result in damage to the EVM, or
personal injury.
Do not touch high voltage terminals.
The EVM may get hot.
3. Connect the VBUS terminal (J1 pin 2) to the desired bus voltage (likely either IN+ or IN–).
4. Connect the system ground to the GND terminal (J1 pin 1).
5. Power on the system, and observe the device states and outputs through the GUI.
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5.2.3 Direct EVM USB Communication
If desired, the EVM can be communicated with directly without the use of the GUI through the USB port. This is
done by sending the desired command string over the serial COM port and receiving the results either through
the COM port or the USB BULK channel, based on the mode. This is useful for interfacing the EVM with custom
setups, scripts, or GUIs.
5.2.3.1 Standard USB CDC Read and Write Operations
Use the serial COM port to read and write registers through USB CDC commands using the following format:
• Read register format: rreg ADR
– Where ADR is the address in hex, and rreg is always lower case
– Register addresses can be in upper or lower case, and do not need to be led by '0x'. 0 padding register
addresses is also optional. For example, to read register address 0xB, some valid commands include:
• rreg b
• rreg 0B
• rreg 0x0B
– When '0x' is used, the 'x' must be lower case.
– For the previous example, the EVM would return the results in JSON format
{"acknowledge":"rreg 0x0B"}
{"register":{"address":11,:"value":3}}
{"evm_state":"idle"}
• Write register format: wreg ADR VAL
– Where ADR and VAL are in hex, and wreg is always lower case
– Register addresses and values can be in upper or lower case, and do not need to be led by '0x'. 0 padding
register addresses and values is also optional. For example, to write register address 0x1 with the value
0xfb69, some valid commands include:
• wreg 1 fb69
• wreg 01 0xfb69
• wreg 0x01 0xFB69
– When '0x' is used, the 'x' must be lower case.
– For the previous example, the EVM would return the results in JSON format:
{"acknowledge":"wreg 0x01 0xfb69"}
{"console":"Writing 0xfb69 to ADC_CONFIG register"}
{"evm_state":"idle"}
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5.2.3.2 Collect Data Through the USB BULK Channel
The "Collect Data" function can also be started and stopped via the serial COM port, however the results will be
sent over the USB BULK Channel. To do this, use the following format:
• Start collecting data format: collect timerPeriod collectFlags channelAddressIDs numDevices
– Where each parameter is the decimal representation of the value in the following format:
• timerPeriod: The delay used in the internal timer to allow data collection sample sets (in milliseconds,
unsigned 32bit value).
• collectFlags: a byte of data that has a 1 to collect and a 0 to not collect each register value type,
according to the following definitions (note to only use energy and charge flags when the device
supports that, otherwise set to 0):
– VSHUNT = 0b1000000
– VBUS = 0b0100000
– DIETEMP = 0b0010000
– CURRENT = 0b0001000
– POWER = 0b0000100
– ENERGY = 0b0000010
– CHARGE = 0b0000001
• channelAddressIDs
– For SPI, each 4 bits is the chip select (CS) line for each EVM chained together starting with the
LSBs (each CS can either be 1, 2, 3 or 4).
• For example, if EVM 1 is on channel 1 and EVM 2 is on channel 3, the value here would be
0b00110001.
– For I2C, this is the 4 LSBs of each address chained together, starting with the LSBs.
• For example If EVM 1 is on channel 0x41 and EVM 2 is on ox43, the value here would be
0b00110001
• NumDevices is the number of EVMs chained together (1-4).
– For example, to start data collection for VSHUNT, VBUS, and DIETEMP every 100 ms, for two INA229s
with EVM 1 CS = 1 and EVM 2 CS = 3, you would send: collect 100 112 49 2
• For this example, the EVM would return the acknowledgment and status in JSON format:
{"acknowledge":"collect 100 112 49 2"}
{"evm_state":"collecting"}
• Note, for the rreg and wreg functions above, the EVM will return "collecting" instead of "idle" if
collecting.
– The USB BULK channel receives data in the format: frameID deviceNumID address registerSize data
• Where each parameter is the decimal representation of the value in the following format:
– frameID (1 byte): Always reeds 0. Used to ensure data is aligned.
– deviceNumID (1 byte): An ID number corresponding to the EVM number.
• From the above example, this will be 1 if reading from EVM 1 which had CS set to 1, and 2 if
reading from EVM 2 which had a CS set to 3.
– address (1 byte): The register address that was read from the device.
– registerSize (1 byte): The number of bytes that the following data will have.
– data (1 byte at a time): The register data value, given in bytes with the most significant byte first.
• Stop collecting data format: stop
– The EVM would return the acknowledgment and status in JSON format:
{"acknowledge":"stop"}
{"evm_state":"idle"}
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5.2.4 PAMB Compatibility
If desired, this EVM and GUI can be used with the PAMB Controller (DC081A) by jumper wiring the pin headers
of the PAMB to the EVM. Figure 5-12 shows which pins on the PAMB correspond to the EVM header pins. Note
not to add too much resistance in the jumper wire connection setup or the signal may degrade and cause
communication errors.
Figure 5-12. EVM to PAMB Connection
The new GUI and firmware can also be used with the SENS063A and SENS064A and PAMB Controller. If the
firmware does not update automatically, DFU mode may need to be entered manually. See Section 5.2.1.2.1.
When using SENS064A on the PAMB with the new GUI/Firmware, only 1 device can be used at a time, with
SW1 on the EVM set to CS3, and the GUI switch setting set to CS1.
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6 Circuitry
This section summarizes the EVM subsystems and their components.
6.1 Current Sensing IC
This section describes the main INA device and supporting components.
U1 is the main INA current-sensing device (either the INA228, INA229, INA237, INA238, or INA239). C1 and C2
are bypass capacitors that are placed near the sensor to help mitigate power supply noise and provide current
quickly to the device when needed. LED D1 with current limiting resistor R4 are used to indicate when the EVM
is powered on.
The device pins can be monitored directly through the test points TP1 – TP12. Note that there are two extra test
points on GND for convenience.
6.2 Input Signal Path
This section describes the circuitry of the input signal path.
J1 is the main connection terminal. Pin 1 of J1 is used to tie the system ground to the EVM ground. Pin 2 of J1 is
used for the VBUS measurement within the sensor. Pins 3 and 4 are tied to IN–, and Pins 5 and 6 are tied to IN
+. There are two pins each for IN– and IN+ for convenience.
R1 can be used for an optional onboard shunt resistor with a 2512 footprint. Alternatively, a shunt can be placed
across the IN+ and IN– terminals of J1. If desired, a differential voltage can be applied directly for measurement
tests.
C3, R2, and R3 combine to make an optional input filter. R2 and R3 are populated with 0-Ω resistors by default.
When using input filtering, take into account the input bias current of the device.
6.3 Digital Circuitry
This section describes the digital circuitry around the device.
6.3.1 I2C (INA228, INA237, INA238)
J2 and J3 are the main header pins that connect the digital and power pins to the SCB Controller or other EVMs.
J3 connects to the EVM/SCB on the right, while J2 connects to more EVMs on the left. R5 and R6 are used as
pullup resistors for the main digital IO pins.
SW0 and SW1 set the I2C address of the device. This can be useful when using the EVM with a custom
controller (other than the SCB Controller), or when connecting multiple EVMs together. Currently the SCB
Controller and GUI are set up to use four EVMs at a time.
R8 is used as a pullup resistor for the ALERT pin, which is routed to both J2 and J3. LED D2 and current limiting
resistor R7 are used to indicate when the ALERT has triggered.
6.3.2 SPI (INA229, INA239)
J2 and J3 are the main header pins that connect the digital and power pins to the SCB Controller or other EVMs.
J3 connects to the EVM/SCB on the right, while J2 connects to more EVMs on the left. R7–R10 are 0-Ω resistors
in series with the main digital IO pins. Optionally, these resistor spaces can be used to provide inline filtering on
the digital lines, or the resistors can be removed to disconnect the digital pins from the header pins.
SW1 is used to redirect the control signal line (CS) to 1 of 4 pins on J2 and J3. This can be useful when using
the EVM with a custom controller (other than the SCB Controller), or when connecting multiple EVMs together.
Currently the SCB Controller and GUI are set up to use four EVM at a time. (Note, if using the PAMB Controller
and the SENS064A EVM, you can only use one EVM at a time, with SW1 on the EVM set to CS3, and the GUI
switch setting set to CS1.)
R6 is used as a pullup resistor for the ALERT pin, which is routed toJ2 and J3. LED D2 and current limiting
resistor R5 are used to indicate when the ALERT has triggered.
Circuitry www.ti.com
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7 Schematics, PCB Layout, and Bill of Materials
Note
Board layouts are not to scale. These figures are intended to show how the board is laid out. The
figures are not intended to be used for manufacturing EVM PCBs.
7.1 Schematics
This section shows the schematics separately for the SENSo63 and SENS064
7.1.1 SENS063 (INA228EVM, INA237EVM, INA238EVM)
Figure 7-1 and Figure 7-2 show the schematic of the EVM. Figure 7-1 shows the circuitry for the EVM. Figure
7-2 shows the mechanical components included with the EVM.
INA228AIDGSR/
A1 1
A0 2
ALERT 3
SDA 4
SCL 5
VS
6
GND 7
VBUS
8
IN-
9
IN+
10
U1
GND
0
R2
0
R3
100V
0.1uF
C3
DNP
GND
GND
1
2
3
4
5
6
J1
TP8
SDA
TP9
SCL
TP11
A1
TP10
A0
TP12
ALERT
PD2
TP5
GND
TP6
GND
TP2
IN-
TP4
IN+
TP1
VBUS
TP3
VS
0.1uF
C2
D2
10k
R7
+3V3
+3V3
1µF
C1
4.7k
R8
D1
10k
R4
4.7k
R5
4.7k
R6
+3V3
+3V3
PN5
PN4
PN5
PN4
GND
+3V3
GND
PN5
PN4
GND
+3V3
GND
MNT_1
7
MNT_2
8
MNT_3
9
MNT_4
10
1
2
3
5
6
4
SW0
CUS-14TB
MNT_1
7
MNT_2
8
MNT_3
9
MNT_4
10
1
2
3
5
6
4
SW1
CUS-14TB
0.01
R1
DNP
+5V
+3V3
1
3
56
4
2
7
910
8
12 11
J2
1
3
5
7
9
11
J3A
2
4
6
8
10
12
J3B
GND
+5V
+3V3
GND
PN4
PN5
PD2
PP1
PP0
PQ3
PQ2
PQ0
PQ1
PD2
PN5
PN4
TP7
GND
INA237AIDGSR/
INA238AIDGSR
Figure 7-1. SENS063 Schematic
www.ti.com Schematics, PCB Layout, and Bill of Materials
SBOU241B – APRIL 2020 – REVISED DECEMBER 2020
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INA228, INA229, INA237, INA238, and INA239 EVM User’s Guide 19
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LOGO
PCB
Texas Instruments
FID2
DNP
FID1
DNP
FID3
DNP
SENS063
B
PCB Number:
PCB Rev:
Label Assembly Note
ZZ1
This Assembly Note is for PCB labels only
Assembly Note
ZZ2
These assemblies are ESD sensitive, ESD precautions shall be observed.
Assembly Note
ZZ3
These assemblies must be clean and free from flux and all contaminants. Use of no clean flux is not acceptable.
Assembly Note
ZZ4
These assemblies must comply with workmanship standards IPC-A-610 Class 2, unless otherwise specified.
Variant/Label Table
Variant Label Text
001 INA228EVM
002 INA237EVM
CE Mark
LOGO
PCB
FCC disclaimer
LOGO
PCB
WEEE logo
Size: 0.65" x 0.20 "
PCB Label
LBL1
THT-14-423-10
LOGO5
DANGER HIGH VOLTAGE
LOGO6
CAUTION HOT SURFACE
003 INA238EVM
MECH
H5
SENS077
MECH
H6
6612041
H2
SJ5382
H3
SJ5382
H1
SJ5382
H4
SJ5382
Assembly Note
ZZ5
Trim the leads under J1 (back of PCB) to give clearance from surface
Figure 7-2. SENS063 Hardware Schematic
Schematics, PCB Layout, and Bill of Materials www.ti.com
20 INA228, INA229, INA237, INA238, and INA239 EVM User’s Guide SBOU241B – APRIL 2020 – REVISED DECEMBER 2020
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