Texas Instruments LED171596AEVM User manual

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Using the LED171596AEVM Evaluation Module
User's Guide
SNVU546C–October 2017–Revised May 2018
Using the LED171596AEVM Evaluation Module
The Texas Instruments LED171596A evaluation module (EVM) helps designers evaluate the operation
and performance of the LED171596A 96-LED driver. The LED171596A is an LED matrix driver that can
individually control up to 96 LEDs. To control the 96 LEDs it uses four high-side PMOS switches and 24
low-side programmable current sinks. The driver has 9-bit duty cycle and 8-bit current control of each low
side LED current sink. They can be individually controlled through the I2C-compatible or SPI interface.
The EVM contains one LED171596A (see Table 1) and one LEDARRAYEVM with 96 white LEDs. The
TIVA EK-TM4C123GXL Launchpad, NOT included in the EVM kit, is required to run the GUI software.
Contents
1 Introduction ................................................................................................................... 3
2 Setup .......................................................................................................................... 3
2.1 Input/Output Connector Description.............................................................................. 3
2.2 Operation ............................................................................................................ 4
3 EVM Software................................................................................................................ 4
3.1 Minimum Procedure for Turning on the LEDs .................................................................. 5
3.2 EVM and Tiva LaunchPad Setup................................................................................. 5
3.3 Tiva ICDI Driver installation in Windows 7 ...................................................................... 7
3.4 Tiva ICDI Driver installation in Windows 10..................................................................... 7
3.5 Programming the Firmware ....................................................................................... 8
3.6 EVM Software Installation ......................................................................................... 8
3.7 EVM Software Launch............................................................................................ 10
3.8 Status Bar .......................................................................................................... 10
3.9 Main Menu ......................................................................................................... 11
3.10 Information View................................................................................................... 11
3.11 Register View...................................................................................................... 12
3.12 Control Menu....................................................................................................... 13
4 Board Layout................................................................................................................ 25
5 Schematic ................................................................................................................... 30
6 Bill of Materials (BOM)..................................................................................................... 32
List of Figures
1 LED171596AEVM ........................................................................................................... 4
2 Set Jumper Pins ............................................................................................................. 4
3 Tiva LaunchPad (EK-TM4C123GXL) and LED171596A EVM ........................................................ 5
4 USB Cable Connection and PWR Switch Setting, TM4C123GXL .................................................... 5
5 Connect Evaluation Board and LaunchPad.............................................................................. 6
6 Win7 Stellaris Virtual Serial Port on Device Manager .................................................................. 7
7 Win7 Stellaris In-Circuit Debug Interface on Device Manager......................................................... 7
8 Win10 Stellaris Virtual Serial Port on Device Manager................................................................. 7
9 Win10 Stellaris In-Circuit Debug Interface on Device Manager ....................................................... 7
10 LM Flash Programmer ...................................................................................................... 8
11 Ready to Install .............................................................................................................. 8
12 Setup LED171596A EVM................................................................................................... 9
13 LED171596AEVM Setup Wizard......................................................................................... 10

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14 Desktop Icon................................................................................................................ 10
15 Status Bar (Hardware Connected)....................................................................................... 10
16 Main Menu .................................................................................................................. 11
17 Information View............................................................................................................ 11
18 Register View (Collapsed) ................................................................................................ 12
19 Register View (Expanded) ................................................................................................ 12
20 Control View (Control Tab)................................................................................................ 13
21 I2C/SPI Selection .......................................................................................................... 14
22 Enable Pin, IFSET/Latch Pin ............................................................................................. 14
23 LED ON/OFF Control...................................................................................................... 15
24 LED Brightness or Current Control ...................................................................................... 15
25 LED Setting Values ........................................................................................................ 16
26 Group Set Button........................................................................................................... 16
27 Group Selection ............................................................................................................ 17
28 Grouped LEDs.............................................................................................................. 17
29 Display Disable Set Button................................................................................................ 17
30 Disabled Selection ......................................................................................................... 18
31 Disabled LEDs.............................................................................................................. 18
32 Sloper Selection............................................................................................................ 19
33 Sloper Set Button .......................................................................................................... 19
34 Sloper LEDs ................................................................................................................ 19
35 SW Latch and Auto Latch Selection..................................................................................... 20
36 Register Direct Access .................................................................................................... 20
37 ISET.......................................................................................................................... 20
38 Enable Bit Control.......................................................................................................... 20
39 LED Driver Register Information ......................................................................................... 21
40 LED Driver Register Configuration....................................................................................... 21
41 PWM Register Information................................................................................................ 21
42 External PWM .............................................................................................................. 22
43 CONFIG_PWM Register Configuration ................................................................................. 22
44 Master Sloper Setting...................................................................................................... 22
45 Status Register ............................................................................................................. 23
46 Interrupt Status/Mask/Clear............................................................................................... 23
47 Log ........................................................................................................................... 23
48 Console...................................................................................................................... 24
49 Top Assembly Layer....................................................................................................... 25
50 Top Layer Routing ......................................................................................................... 26
51 Mid Layer 1 Routing ....................................................................................................... 27
52 Mid Layer 2 Routing ....................................................................................................... 28
53 Bottom Layer Routing ..................................................................................................... 29
54 Schematic Page1 .......................................................................................................... 30
55 Schematic Page2........................................................................................................... 31
Trademarks
Tiva is a trademark of Texas Instruments.
Stellaris is a registered trademark of Texas Instruments.
Windows is a registered trademark of Microsoft Corporation.
All other trademarks are the property of their respective owners.

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1 Introduction
Table 1. Device and Package Configurations
CONVERTER IC PACKAGE
U1 LED171596A VQFN (48)
2 Setup
This section describes the jumpers and connectors on the EVM as well as how to properly connect, set
up, and use the LED171596AEVM. The input voltage range for VIN is 0 V to 17 V with the input voltage
range for VLis 0 V to 6.1 V.
2.1 Input/Output Connector Description
• SEL* (J1) – is provided to allow LED171596A EVM to work with multiple TI Launchpad. The jumper
should be installed between J1-1 and J1-2 for normal operation with EVM GUI (Tiva Launchpad).
• J1/J3 and J2/J4 – is the TI Launchpad connector interface.
• ISET (J2) – is provided to configure the max output current setting via fixed resistor or I2C
programmable rheostat. The recommended setting is with a jumper installed between J2-2 and J2-3 for
I2C programmable rheostat control of ISET.
• IVDD (J3) – is provided to easily measure VDD supply current. The jumper must be installed between
J3-1 and J3-2 for normal operation.
• VLED_SEL (J4, J5, J6) – creates a star jumper and is provided to select the VLED supply. The jumper
should be installed between J4-1 and J4-2 for normal operation (VLED supplied by TPS62140).
• VEXT (J7) – is provided to connect an external supply to The LED171596AEVM. Use J7-3 (VIN) and
J7-2 (GND) to supply power to the TPS62140. Use J7-1 (VL) and J7-2 (GND) when using external
supply for VLED power.
• BEN (J8) – is provided to disable the TPS62140 when using either 5 V or external power connection to
VLED. The jumper should be installed between J8-1 and J8-2 for normal operation (VLED supplied by
TPS62140). When the jumper is removed the TPS62140 output will be disabled.
• VIN_SEL (J9) – is provided to select either 5V supply from Tiva Launchpad or external power supply.
The connection from Tiva Launchpad is limited by PC USB current limit and should only be used under
low LED brightness/current conditions. The jumper should be installed between J9-2 and J9-3 for
normal operation (external supply).
• LED_BD (J10) – is the output connector to external LEDARRAY board.
• EXP_IN (J11) – is the expansion input connector and is provided to allow expansion of up the 4
additional LED171596AEVM (5 total).
• EXP_OUIT (J12) – is the expansion output connector and is provided to allow expansion of up the 4
additional LED171596AEVM (5 total).

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Figure 1. LED171596AEVM
2.2 Operation
For proper operation of the LED171596A, IVDD, VLED_SEL, SEL*, ISET, VIN_SEL, BEN must be
properly configured. The recommended setting, using shorting blocks is as follows:
• IVDD : Shunt installed between pins J3-1 and J3-2.
• VLED_SEL: Shunt installed between pins J4-1 and J4-2.
• VIN_SEL: Shunt installed between pins J9-2 and J9-3.
• SEL*: Shunt installed between pins J1-1 and J1-2 (Tiva Launchpad).
• ISET: Shunt installed between pins J2-2 and J2-3 (Rheostat variable ISET control).
• BEN: Shunt installed between pins J8-1 and J8-2 (TPS62140 enabled).
Refer to Figure 2 for all jumper positions.
Set up jumper pins as shown in Figure 2.
Figure 2. Set Jumper Pins
3 EVM Software
EVM software is available for download from the TI website. The LED171596AEVM is connected via USB
to the computer and controlled with special EVM software (Windows®7/10 compatible). An EK-
TM4C123GXL, Tiva™ LaunchPad (http://www.ti.com/tool/ek-tm4c123gxl), is used with the EVM to provide
I2C/SPI communication, and external PWM, EN, IFSEL/LATCH pin control with the LED171596A via USB.

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Figure 3. Tiva LaunchPad (EK-TM4C123GXL) and LED171596A EVM
3.1 Minimum Procedure for Turning on the LEDs
The minimum procedure for turning on the LEDs is as follows:
1. Set the Power Select Switch on Tiva LaunchPad to debug (refer to Figure 4).
2. Connect the LaunchPad board to the LED171596AEVM board (refer to Figure 5).
3. Verify jumper pin setting (refer to Figure 2).
4. Connect micro USB cable to the debug port of LaunchPad board and connect PC (refer to Figure 4).
5. Install Tiva ICDI driver.
6. Verify the “Tiva Stellaris®Virtual Serial Port” and “Stellaris In-Circuit Debug Interface” on Windows
Device Manager.
7. Connect optional external power and ground to the board.
8. Turn on the external supplies (if used).
9. Install and run EVM software.
10. Make sure the “Hardware Connected” message on the status bar.
11. Click “Control” menu.
12. Click “Enable Pin” button.
13. Click “Enable Backlight” checkbox.
3.2 EVM and Tiva LaunchPad Setup
Connect a micro USB cable to the debug port (power/ICDI) and set the power select switch (PWR
SELECT) to debug (ICDI).
Figure 4. USB Cable Connection and PWR Switch Setting, TM4C123GXL

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Connect Tiva LaunchPad and EVM (BOOSTXL-LED171596A) as shown in Figure 5.
Figure 5. Connect Evaluation Board and LaunchPad
Connect external power and ground to the EVM board (BOOSTXL-LED171596A).

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3.3 Tiva ICDI Driver installation in Windows 7
To use Tiva LaunchPad, install Stellaris ICDI Drivers. The driver file can be downloaded from www.ti.com
and the document Stellaris® In-Circuit Debug Interface (ICDI) and Virtual COM Port” provides more detail
information about how to install the driver.
Connect USB cable to PC. Open “Control Panel →Device Manager” and verify the “Stellaris Virtual Serial
Port” and “Stellaris In-Circuit Debug Interface”. If those steps do not work, reinstall Tiva ICDI Driver.
Figure 6. Win7 Stellaris Virtual Serial Port on Device Manager
Figure 7. Win7 Stellaris In-Circuit Debug Interface on Device Manager
3.4 Tiva ICDI Driver installation in Windows 10
The first step is to check that the driver for Tiva Launchpad is installed correctly on the system. If the
driver is installed correctly, you should see the virtual com port show up in Device Manager as shown in
Figure 8. Note that the actual COM number will vary . The COM port should be identified as “Stellaris
Serial Virtual Port (COMX)”.
If the COM port is identified as “USB Serial Device (COMX)”, the ICDI driver is not installed correctly.
Navigate to the folder where the driver is downloaded, right click on the file stellaris_icdi_com.inf, and
select install (see Figure 9). Once installation is complete the name of the virtual com port will change
from “USB Serial Device (COMX)” to “Stellaris Virtual Serial Port (COMX)”.
Figure 8. Win10 Stellaris Virtual Serial Port on Device Manager
Figure 9. Win10 Stellaris In-Circuit Debug Interface on Device Manager

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3.5 Programming the Firmware
The very first time GUI is connected to the EVM via Launchpad; it will attempt to reprogram the
Launchpad firmware. The firmware reprogramming is required for GUI to properly communicate with the
EVM. The firmware on a fresh Tiva Launchpad will show a constantly changing color LED. Once the
Launchpad is reprogrammed by the GUI the LED color and pattern will change as follows:
• When there is no communication the LED will be solid blue color.
• When there is communication the LED will be blinking red/purple color.
The first time the GUI updates the firmware it can take up to 5 minutes. If the update takes more than 5
minutes the firmware will need to be installed using LM Flash Programmer. The LM Flash Programmer
can be downloaded from www.ti.com . Launch the programmer, select “TM4C123G Launchpad” in
“Configuration tab” (refer to Figure 10). Then select “Program” tab; navigate to the folder where GUI is
installed. By default installation, it should be “C:\Program Files (x86)\Texas Instruments\LED171596A
EVM”, select tivafw.bin and click the [Program Button].
Figure 10. LM Flash Programmer
3.6 EVM Software Installation
Execute setup_LED171596A_EVM.msi file: If it is compressed in zip file format, unzip first in any location
and then click “Run” button though Windows security warning message appears. Click next button.
Figure 11. Ready to Install

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Figure 12. Setup LED171596A EVM
Check to accept the agreement and click “Next” button to proceed with installation.
Click “Next” button. By default, program will be installed in C:\Program Files (x86)\Texas
Instruments\LED171596A folder and Texas Instruments\LED171596AEVM in start menu.
Click ‘Next’” button to proceed with installation.
Check to create a desktop icon for the program and check to launch EVM software after installation.

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Figure 13. LED171596AEVM Setup Wizard
3.7 EVM Software Launch
Run ‘C:\Program Files (x86)\Texas Instruments\ LED171596A EVM\LED171596A_EVM.exe’ if default
installation folder was not modified in the “EVM software installation” step or click the desktop icon
“LED171596A EVM”.
Figure 14. Desktop Icon
3.8 Status Bar
The status bar at the bottom of EVM software screen provides information regarding hardware connection
status, I2C/SPI communication status, and software versions. Once the EVM software is connected to the
hardware and starts to communicate with the firmware of Tiva LaunchPad, “Hardware Connected” and
Light Blue sign is displayed.
Figure 15. Status Bar (Hardware Connected)

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3.9 Main Menu
There are three available views of main menu: “Info”, “Register”, and “Control”. The components in each
view are synchronized so any changes performed in one view of menu are automatically updated in the
others.
Figure 16. Main Menu
3.10 Information View
The Information view is shown when EVM software is started or ‘Info’ icon is clicked, and it provides brief
information of the LED171596A. For more detail information, refer to the LED171596A datasheet.
Figure 17. Information View

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3.11 Register View
The register view is shown when ‘Register’ icon is clicked, and it provides the register values, field values,
and descriptions.
Figure 18. Register View (Collapsed)
Figure 19. Register View (Expanded)

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Enter the desired hex value to the registers (“Current Value” column), perform a bit-wise configuration of
any register fields by double-clicking on the corresponding register bit or configure a register field by
entering the desired hex value in the "Value" column located under the "Field View". "Field View" displays
the description of all fields of the selected register. Each register can be read independently or all registers
can be read at once by utilizing the “Read” and “Read All” buttons, respectively. The data is written to the
register(s) in one of two ways, depending on the “Update Mode” field selection: In Immediate mode, the
register data is written immediately following a “Current Value”, an individual bit or a "Value" change. In
“Deferred” mode, the displayed data is written to all registers upon depression of the “Write” button.
Press “Read All” button to read back all the registers and the values will be updated on this table. If any
register values need to be changed, simply double click on the individual bit values to change it in this
table or press “Write Register” button to write all the registers at a time if “Deferred” is selected instead of
“Immediate” from dropdown box.
Register settings can be saved to text file format by clicking "Save" button or selecting “Save Registers”
from file menu.
Register settings saved as text file format can be opened and programmed automatically by clicking
"Load" button or selecting “Load Register” from file menu.
3.12 Control Menu
The Control view is shown when ‘Control’ icon is clicked, and it provides easy ways to control registers
and pin values.
There are two tabs available under the “Control” view: "Control” and "Log”. The left side of these tabs
contains the controls for the corresponding block of the LED171596A. The right side contains data log.
Differently to the Registers view control, the Control view does not provides deferred mode but provides
immediately mode only.
Figure 20. Control View (Control Tab)

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3.12.1 Establishing I2C/SPI Communication
I2C or SPI is can be selected. IFSEL pin need to be set to high when I2C is selected because
IFSEL_LATCH is used for selecting between I2C-compatible and SPI after rising edge of EN pin.
Figure 21. I2C/SPI Selection
3.12.2 EN and IFSEL/Latch Pin Control
EN and IFSEL_LATCH pins can be controlled by using the Enable Pin button and the IFSeL Pin button
respectively, but the Enable Pin button is not valid if a Tiva Launchpad is not connected to PC. The button
color is turned red when the pin value is set to high and gray is low. IFSEL pin selects I2C-compatible or
SPI interfaces at rising edge of EN pin (see Figure 22). After detecting interface “IFSEL Pin” is turned to a
latch pin to support latch input for brightness and current register buffers when in normal mode. As a
default, “Latch pin” button is disabled because the evaluation software supports automatic latch pin control
every time when a value written to SRAM. “Latch pin” button is enable when automatic latch is disabled
(see Section 3.12.8).
Figure 22. Enable Pin, IFSET/Latch Pin
3.12.3 LED Brightness and Current Control
Individual LED’s current and brightness can be controlled through the LED buttons, LED brightness
trackbar/text, and LED current trackbar/text. There are buttons and texts, which are ordered in the same
order as the LEDs on the LED171596AEVM. Simply, a LED can be turned on or turned off is available
when a button is clicked. Brightness 0 is written into the LEDxx_BRI(0x160 + LED number) reigster when
the LED is turned off, LED brightness/current values configured by trackbars are written to
LEDxx_BRI(0x160 + LED number) register and LEDxx_CUR(0x100+LED number) register at once.
Therefore, LED must be turned off and then turn on to change the brightness or the current settings.

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Figure 23. LED ON/OFF Control
Clicking buttons with Left-Ctrl key provides a way to change the brightness value or the current value
independently, or to control more than one LED simultaneously. The selected buttons turn red, and the
update buttons are shown on the LED brightness track bar and LED current track bar. The brightness or
current value of LEDs marked in red are updated when the update button is clicked. It turns back to
normal mode if a button clicked without Left-Ctrl key.
Figure 24. LED Brightness or Current Control

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3.12.4 LED Setting Values
All the setting value regarding each LEDs can be verified on the LED button and texts. The value on the
LED button in hexa format is LEDxx_BRI register(0x160+ LED number) value and the value of tool tip is
LEDxx_CUR regsier (0x100+LED number) value. The tool tip of the button will be shown when mouse
point moves on a LED button. If the bits of group, disable, or sloper of LED are set, the information is
shown under the LED button. For example, G2 means the LED is grouped as Group 2, D means the LED
is disabled and S means the Slope bit of the LED is set.
Figure 25. LED Setting Values
3.12.5 LED Group Setting
LED Group registers(0x1DE – 0x1F1) can be set through the “Group Selection” pop-up window shown
when “Group Set” button is clicked.
Figure 26. Group Set Button

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Figure 27. Group Selection
LED Buttons for group selection are ordered in the same order as the LEDs on the LED171596A
evaluation board and current group selection value is displayed on the button. To change group selection
value, select the LED or LEDs and then click “Group1”, “Group2”, “Group3” or “UnGroup” button. All
Group1 LEDs can be set to ungroup value at once if click “UnGroup 1” button. “UnGroup 2” and “UnGroup
3” buttons provide same function for the Group2/3 LEDs. The newly configured values are transferred to
EVM when “Done” button is clicked, and the grouped LEDs display own group number.
Figure 28. Grouped LEDs
3.12.6 LED Disable Setting
LED Disable registers(0x1C1 – 0x1CC) can be set through the “Disable Selection” pop-up window shown
when “Disable Set” button is clicked.
Figure 29. Display Disable Set Button

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Figure 30. Disabled Selection
LED Buttons for disable selection are ordered in the same order as the LEDs on the LED171596AEVM
and current disable selection value is displayed on the button. To change disable selection value, select
the LED or LEDs and then click “Disable” or “Enable” button. The newly configured values are transferred
to the EVM when “Done” button is clicked, and the disabled LEDs display own status as ‘D’.
Figure 31. Disabled LEDs
3.12.7 LED Sloper Setting
LED Sloper registers(0x1CF – 0x1DA) can be set through “Sloper Selection” pop-up window shown when
the “Sloper Set” button is clicked.

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Figure 32. Sloper Selection
Figure 33. Sloper Set Button
LED Buttons for sloper selection are ordered in the same order as the LEDs on the LED171596AEVM and
current sloper selection value is displayed on the button. To change sloper selection value, select the LED
or LEDs and then click “UnSloper” or “Sloper” button. The newly configured values are transferred to EVM
when “Done” button is clicked, and the sloper LEDs display their status as ‘S’.
Figure 34. Sloper LEDs
3.12.8 SW Latch and Auto Latch
By default, the evaluation software supports automatic latch pin control so latch pin set high and low every
time when a value is written to SRAM to trigger updates of SRAM buffer. If ‘Auto Latch’ is unchecked,
Auto latch function is disabled, and a latch pin signal is required manually. There are two ways to control
latch signal. One is to click “latch pin” button. Another way is to write 1b data into Bit[0] of LATCH register
(0x02), “SW Latch” button.

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Figure 35. SW Latch and Auto Latch Selection
3.12.9 Register Direct Access
The Direct Access provides another way to access to the registers. To read a register put the register
number into “Reg(hex)” text box and click the ‘Read’ button. To write the specific value into a register put
the register number and the data into “Reg(hex)” and “Data(hex)” text boxes respectively, and then click
‘Write’ button. The buttons from ‘00’ to ‘15’ provides bit data writing. Red color means bit data ‘1b’, and
gray color bit data ‘0b’. When the bit button is clicked, the bit data is reversed and register data is written
immediately.
Figure 36. Register Direct Access
3.12.10 ISET Control
The maximum current reference of the LED driver (constant-current sink) can be set using ISET. The EVM
GUI provides 10 mA, 12.5 mA, 20 mA, 30 mA, 40 mA, 50 mA, and 60 mA. Disable the LED171596A
backlight before changing the ISET jumper setting or the ISET value.
Figure 37. ISET
3.12.11 Enable Backlight Control
The bit 0 of register 0x00 can be controlled using “Enable Backlight” check box:
• Unchecked - LED driving disabled. Device stays in STANDBY.
• Checked - LED driving enabled.
Figure 38. Enable Bit Control
3.12.12 LED Driver Control
the LED driver group box provides information and control of LED_DRIVER_CONTROL Register (0x21).