3 Modifications
The design of the TPS56C20EVM-614 provides access to all the four devices of the IC family: TPS56520,
TPS56720, TPS56920, and TPS56C20. The module ships with a TPS56C20 IC soldered but the user can
replace the TPS56C20 with any of the other three ICs to test their performance.
3.1 Output Voltage Set Point
To change the output voltage of the TPS56C20EVM-614, change the value of resistor R7. Calculate the value of
R7 for a specific output voltage between 0.6 V to 1.87 V using
.
V
OUT
= 0.6 × (1 + R7 / R8)
(1)
lists the R7 values for common output voltages. For higher output voltages, a feed forward capacitor
(C12) may be required to improve phase margin. The evaluation module provides pads to include the
component (C12). NOTE: the values given in
are standard values and not the exact value.
Table 3-1. Output Voltages
Output Voltage
(V)
R7 (kΩ)
R8 (kΩ)
C12 (pF)
L1 (µH)
C6 + C7 (µF)
MIN
TYP
MAX
0.8
7.33
22
1
14.7
22
1.0
1.5
2.2
44 – 100
1.1
18.2
22
1.0
1.5
2.2
44 – 100
1.2
22
22
1.0
1.5
2.2
44 – 100
1.5
33
22
1.0
1.5
2.2
44 – 100
1.8
44.2
22
Optional
1.0
1.5
2.2
44 – 100
3.2 Output Voltage Set Point Using I2C Interface
The engineer can change the TPS56C20 output voltage by using an I2C interface which can dynamically scale
the output voltage in the range of 0.6 V to 1.87 V.
,
, and
explain the
procedure to download all the software required and how to communicate between the evaluation module and
the PC. The design includes an easy-to-use GUI so that the design engineer can test the I2C functionality
without much prior experience. The test requires a PC running the Microsoft
®
Windows
®
operating system,
the TI USB2ANY interface, and USB2ANY_GUI software. The design engineer can purchase the TI USB2ANY
interface from the TI website.
3.2.1 PC Preparation
Use the following steps to prepare the PC for use:
1. Turn on the PC and boot up the Windows operating system.
2. Copy the provided file “PC-Software.zip” to a directory on the system hard drive.
3. Uncompress the files to that directory.
4. From the directory listing, unzip the USB2ANY_SDK_SETUP program files and run the
USB2ANY_SDK_Setup.exe with the default settings.
5. From the directory listing, unzip the TPS56X20 I2C TEST PANEL file and run the SETUP file from the
TPS56X20 I2C TEST PANEL Installer.
6. Reboot the PC after installing both pieces of software.
3.2.2 Connect the PC
Use the following steps to connect the PC to the TI USB2ANY interface:
1. Connect the provided USB cable between the PC USB port and the TI USB2ANY interface as illustrated in
2. Connect the supplied 10 conductor ribbon cable between the TI USB2ANY interface and PWR614 J4
connector.
3. Turn on or enable the input voltage power supply.
Modifications
SBAU227A – MARCH 2014 – REVISED JUNE 2021
TPS56C20 Buck Converter Evaluation Module User's Guide
5
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