Texas Instruments TPS65020EVM-110 User Manual

User's Guide

SLVU138 – August 2005

TPS65020EVM-110 User's Guide

This User’s Guide describes the characteristics, operation, and use of the
TPS65020EVM-110 evaluation module (EVM). This EVM is designed to help the user
evaluate and test the various operating modes of the TPS65020. This User’s Guide
includes setup instructions for the hardware and software, a schematic diagram, a bill
of materials (BOM), and PCB layout drawings for the evaluation module.

Contents

1 Introduction .......................................................................................... 1

2 Setup ................................................................................................. 2

3 Board Layout ........................................................................................ 3

4 Schematic and Bill of Materials ................................................................... 8

5 Related Documentation .......................................................................... 10

List of Figures

1 Assembly Layer ..................................................................................... 4

2 Top Layer ............................................................................................ 5

3 Routing, GND Plane................................................................................ 6

4 Routing, VIN Plane ................................................................................. 7

5 Routing, Bottom Layer ............................................................................. 8

6 TPS65020EVM-110 Schematic ................................................................... 9

1 HPA110A BOM .................................................................................... 10

1 Introduction

The Texas Instruments TPS65020EVM is an integrated Power Management IC for applications that are
powered with one Li-Ion or Li-Polymer cell, and require multiple power rails. The TPS65020 contains three
highly efficient switching step-down converters, two LDOs, and additional status and I/O pins. The device
is controlled via an I2C™ interface.

1.1 Requirements

In order for this EVM to operate properly, the following components must be connected, and properly
configured.

1.2 Personal Computer (PC)

A computer with a USB port is required to operate this EVM. The TPS65020 interface software, which is
run on the PC, communicates with the EVM via the PC USB port. The user sends commands to the EVM
as well as reads the contents of the TPS65020 internal registers through the USB port.

I2C is a trademark of Philips Electronics.

List of Tables

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Setup

1.3 Printed Circuit Board Assembly

The TPS65020EVM-110 PCB contains the TPS65020 IC and its required external components. This
board contains several jumpers and connectors that allow the user to customize the board for specific
operating conditions.

1.4 USB to I2C Interface Board (EV2300)

The EV2300 is the link that allows the PC and the EVM to communicate. One end of the EV2300
connects to the PC with the supplied USB cable, and the other end of the EV2300 connects to the EVM
with the supplied Molex cable. When the user writes a command to the EVM, the interface program, which
is run from the PC, sends the command to the PC USB port. The EV2300 receives the USB command
and converts the signal to an I2C protocol. It then sends the I2C signal to the TPS65020 board. When the
user reads a status register from the EVM, the PC sends a command to read a register on the EVM.
When the EVM receives the command, it reports the status of the register via the I2C interface. The
EV2300 receives the information on the I2C interface, converts it to a USB protocol, and sends it to the
PC.

1.5 Software

Texas Instruments has provided software to assist the user in evaluating this EVM. To install the software,
insert the enclosed CD into your computer. The software should start automatically. If it does not, simply
go to <Start>, <Run>, and type “D:\SLVU138.exe”, and click <OK> (assuming that D: is your CD drive).
The program should run without errors. If any problems occur that result in the program not being
installed, view the readme.txt file on the CD for further information. Check the TPS65020 product folder on
the TI website for the latest revision of the software.

2 Setup

This section describes the jumpers and connectors on the EVM as well as how to properly connect, setup,
and use the TPS65020EVM-110.

2.1 Input / Output Connector Descriptions

INPUT / OUTPUT DESCRIPTION

J1 – VIN

J2 – GND This is the return connection for VI.

J3 – VINLDO/GND

J4 – VSYSIN/GND input to VDCDC1. If an external power supply is used, remove R24. Recommended maximum input

J5 – VBACKUP/GND

J6 – GPIO1/GPIO2

J7 – VRTC/GND Output voltage from the RTC circuit.

J8 – Fault Outputs

J9 – USB This header duplicates the signals from the J20 interface connector.

J10 – VDCDC1

Input voltage from external power supply, recommended maximum 5.5 V. Input current is dependent
on load but is typically below 2 A.

Input voltage and return for LDO1 and LDO2C. Resistor R23 connects this pin to VDCDC1. If an
external power supply is used, remove R23. Recommended maximum input voltage is 5.5 V

Input voltage and return for VSYSIN, one of the input voltages for RTC. Resistor R24 connects this
voltage is 4 V

Input voltage and return for VBACKUP, one of the input voltages for RTC. There is no on board
connections to a voltage input. Recommended maximum input voltage is 4 V.

Direct connection to the GPIO1 and GPIO2 pins. For this EVM, GPIO1 is configured as a
push-button input, and GPIO2 is configured as an LED output.

Four fault outputs are available on this connector:
PWRFAIL - Fault occurs when input voltage is below 3 V. Pulled up to VRTC when safe, low for fail.
INT - Fault occurs when there is a fail on an input or output voltage. It acts as a sum fail. Pulled up

to VIwhen safe, low for fail.
RESPWRON– Low reset signal controlled by SW2, 300 mS. Pulled up to VInormally.
LOWBAT– Fault occurs when input voltage is below 3.6 V. Pulled up to VIwhen safe, low for fail.

Output from DCDC1 switching regulator, maximum output current is 1.2 A, default voltage setting is

3.3 V.

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INPUT / OUTPUT DESCRIPTION

J11 – GND Return for VDCDC1

J12 – VDCDC2 Output from DCDC2 switching regulator, maximum output current 1 A, default voltage setting 2.5 V.

J13 – GND Return for VDCDC2

J14 – VLDO1 Output from the low drop out regulator VLDO1, maximun current out is 50 mA, default value 1.1 V.

J15 – GND Return for VLDO1

J16 –VLDO2 Output from the low drop out regulator, VLDO2 maximum current out is 50 mA, default value 1.3 V.

J17 – GND Return for VLDO2

J18 – VDCDC3 Output from the switching regulator DCDC3, maximum current is 800 mA, default value 1.55 A

J19 – GND Return for VDCDC3

J20 – USB USB interface connector
JP1 – DEF 1 Sets voltage for DCDC1 to 3 V or 3.3 V.
JP2 – DEF 2 Sets voltage for DCDC2 to 2.5 V or 1.8 V.
JP3 – DEF 3 Sets voltage for DCDC3 to 1.55 V or 1.3 V.

JP4 – DCDC1 ON/OFF EN for regulator DCDC1, default setting is ON.
JP5 – DCDC2 ON/OFF EN for regulator DCDC2, default setting is ON.
JP6 – DCDC3 ON/OFF EN for regulator DCDC3, default setting is ON.

JP7 – LDO ON/OFF EN for both LDO1 and LDO2 regulators, default setting is ON.

S1 is a normally open momentary push-button switch that, when pressed, connects VIto GPIO1.

S1 – GPIO1 The GPIO1 input is configured on the TPS65020 as a debounced push button that drives an

ON/OFF circuit with output at GPIO2.
S2 is a normally open momentary push-button switch that, when pressed, connects the HOT_RST

S2 – HOT_RST input of the TPS65020 to GND generating the Hot_Reset pulse. The HOT_RST pin is externally

pulled up.

Board Layout

2.2 Setup

3 Board Layout

The following steps must be followed before the EVM is operated

1. Install the TPS65020EVM Software.

2. Connect input voltages and loads to the EVM.

3. Configure all EVM jumpers to factory setting.
– JP4—ON

– JP1—3.3 V
– JP3—1.55 V
– JP2—2.5 V
– JP5—ON
– JP6—ON
– JP7—ON

4. Connect the Molex cable between the EVM and the EV2300. Note that the Molex cable must connect
to the I2C connector on the EV2300.

5. Connect the USB cable between the computer and the EVM.

6. Turn on all supplies and loads.

7. Run the TPS65020EVM software.

This section provides the TPS65020EVM-110 board layout and illustrations.

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Board Layout

3.1 Layout

Board layout is critical for all switch mode power supplies. Figure 1 through Figure 5 show the board
layout for the TPS65020EVM-110 PWB. The nodes with high switching frequencies and currents are short
and are isolated from the noise sensitive feedback circuitry. Careful attention has been given to the routing
of high frequency current loops. See to the datasheet for specific layout guidelines.

Figure 1. Assembly Layer

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