Texas Instruments TPS61280-585 User manual

User's Guide
SLVU955A–December 2013–Revised June 2014
TPS61280-585 Evaluation Module
This User's Guide describes the characteristics, operation, and use of the TPS61280 evaluation module
(EVM). This EVM enables test and evaluation of the Texas Instruments' TPS61280 device, a 2.3-MHz
(typ.), up to 4.8-V input, step-up dc-dc converter with integrated Pass-Through Mode. This User's Guide
includes EVM specifications, user software description, the schematic diagram, bill of materials, and board
layout. After the release of the A-version device in the summer of 2014, the EVM is assembled with the
TPS61280A (supports PWM mode during startup which is not available for TPS61280).
Contents
1 Introduction ................................................................................................................... 2
1.1 Requirements ....................................................................................................... 2
1.2 Applications.......................................................................................................... 2
1.3 Features.............................................................................................................. 2
2 TPS61280EVM Schematic ................................................................................................. 3
3 Connector and Test Point Descriptions................................................................................... 4
3.1 J1 Input Connectors................................................................................................ 4
3.2 J2 Output Connector ............................................................................................... 4
3.3 Other Connectors................................................................................................... 5
3.4 Jumpers.............................................................................................................. 5
4 TPS61280EVM Assembly Drawings and Layout........................................................................ 7
5 List of Materials .............................................................................................................. 9
List of Figures
1 TPS61280EVM-585 Schematic............................................................................................ 3
2 TPS61280EVM-585 Component Placement............................................................................. 7
3 TPS61280EVM-585 Top Copper .......................................................................................... 7
4 TPS61280EVM-585 Inner Layer 1 ........................................................................................ 8
5 TPS61280EVM-585 Inner Layer 2 ........................................................................................ 8
6 TPS61280EVM-585 Bottom Copper ...................................................................................... 8
7 Quick Connection Overview................................................................................................ 9
8 User Interface of TPS61280EVM-585................................................................................... 10
9 I²C Pull-Up Resistor Setting............................................................................................... 11
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Introduction www.ti.com
1 Introduction
The TPS61280 device provides a power-supply solution for products powered by either a three-cell
alkaline, NiCd or NiMH battery, or a single-cell Li-Ion or Li-polymer battery. The wide input voltage range
is ideal for portable power applications such as mobile phones or computer peripherals. In addition, the
TPS61280 can also maintain its output biased at the input voltage level. In this mode, the synchronous
rectifier is current-limited, and allows external loads (for example, an audio amplifier) to be powered with a
restricted supply. In this mode, quiescent current is reduced to 18 μA. Input current in shutdown mode is
less than 5 μA in order to maximize battery life.
1.1 Requirements
The TPS61280EVM is designed to operate over the full input voltage range and produces a fixed output
voltage.
In order to operate this EVM, only a dc power supply able to deliver between 2.3 V and 4.8 V is required.
1.2 Applications
• Single-Cell Ni-Rich, Si-Anode, Li-Ion, LiFePO4 smart-phones or tablet PCs
• 2.5G, 3G, and 4G mini-module data cards
• Current-limited applications featuring high peak power loads
1.3 Features
• 95% Efficiency at 2.3-MHz operation
• VIN range from 2.3 V to 4.8 V
• 2-μA quiescent current in low IQ pass-through mode
• Integrated pass-through mode (35 mΩ)
• Programmable valley inductor current limit and output voltage via I²C interface
• True pass-through mode during shutdown
• Thermal shutdown and overload protection
• Total solution size < 20 mm², sub 1-mm Profil
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1
2
3
J4
1
2
3
J3
1
2
J10
1
2
J11
1
2
3
J5
150uF
C1
VSELENABLE nBYP
GNDGND
VIN VIN
R1
R2
C12C11C10
1
2
3
J6
2.2k
R5
VIN
VIN
GND
GPIO/PG
VIN
S+
S-
GND
C2 C3 C4
GND
GND
GND
GNDGND GND GND
GND
VIN
5
4
1
2
3
6
J1
5
4
1
2
3
6
J2
VOUT
Ferrite Bead
L2
Ferrite Bead
L3
10µF
C6
10uF
C7 C8 C9
GND
ENABLE VSEL nBYP GPIO
GPIO
VSEL
ENABLE
nBYP
SDA
1
2
3
J7
1
2
3
J8
2.2k
R3
2.2k
R4
VIN
I2C_CONNECTOR
GND
GND
1 2
3 4
5 6
7 8
9 10
J9
EN
A1 GPIO A2
VIN
A3
VIN
A4
VSEL
B1
SCL
B2
VOUT B3
VOUT B4
BYP
C1
SDA
C2
SW
C3 SW
C4
AGND D1
PGND D2
PGND D3
PGND D4
U1
TPS61280YFF
SCL
SCL
SDA
1.5µF
C5
SW
470nH
L1
VOUT
S+
S-
GND
1 1 1
1
1
1 1
1
1
1 1 11 1
1Not Installed
2.3V - 4.8V 2.85V - 4.4V
www.ti.com TPS61280EVM Schematic
2 TPS61280EVM Schematic
Figure 1 illustrates the TPS61280EVM schematic.
Figure 1. TPS61280EVM-585 Schematic
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Connector and Test Point Descriptions www.ti.com
3 Connector and Test Point Descriptions
3.1 J1 Input Connectors
3.1.1 Pin 1 and 2: VIN
This header is the positive connection to the input power supply. The power supply must be connected
between these pins and pins 5 and 6 (GND). Twist the leads to the input supply and keep them as short
as possible. The input voltage must be between 2.3 V and 4.8 V.
3.1.2 Pin 3: Input Sense VIN
This header is intended to measure the input voltage directly on the input capacitor close to the device.
Therefore, a four-wire power and sense supply can be connected. Twist the leads to the sensing
connector.
Pin 4: Input Sense GND
This header is intended to measure the GND close to the input of the device. Therefore, a four-wire power
and sense supply can be connected. Twist the leads to the sensing connector.
3.1.3 Pin 5 and 6: GND
This header is the return connection to the input power supply. Connect the power supply between these
pins and pins 1 and 2 (VIN). Twist the leads to the input supply and keep them as short as possible. The
input voltage must be between 2.3 V and 4.8 V.
3.2 J2 Output Connector
3.2.1 Pin 1 and 2: VOUT
This header is the positive connection of the output voltage. Connect the load between these pins and
pins 5 and 6 (GND).
3.2.2 Pin 3: Output Sense VOUT
This header is intended to measure the output voltage directly on the output capacitors.
3.2.3 Pin 4: Output Sense GND
This header is intended to measure the GND close to the output of the device.
Pin 5 and 6: GND
This is the return connection of the output voltage. Connect the load between these pins and Pin 1 and 2
(VOUT).
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www.ti.com Connector and Test Point Descriptions
3.3 Other Connectors
J9: I²C Connector
This 10-pin header connects the USB-to-GPIO adaptor to the TPS61280EVM-585.
J10: SMA Input Connector
This SMA connector is connected to the input voltage of the converter. It can be used to easily analyze
the noise spectrum of the input voltage with a spectrum analyzer. By default, J10 is not assembled on the
EVM.
3.3.1 J11: SMA Output Connector
This SMA connector is connected to the output voltage of the converter. It can be used to easily analyze
the noise spectrum of the output voltage with a spectrum analyzer. By default, J11 is not assembled on
the EVM.
3.4 Jumpers
3.4.1 J3: Enable Jumper
Placing a jumper across pins EN and ON ties the EN pin to VIN, and enables the device. Placing a jumper
across pins EN and OFF ties the EN pin to GND, which disables the device.
J4: VSEL, Output Voltage Selection
Placing a jumper across pins HIGH and VSEL ties the VSEL pin to VIN, and selects the default output roof
voltage. Placing a jumper across pins LOW and VSEL ties the VSEL pin to GND, and selects the default
output floor voltage.
Table 1. TPS61280 VSEL Settings
Value Description Default Output Voltage
HIGH Selects the Output Roof Voltage as stored in register 0x03 3.15 V
LOW Selects the Output Floor Voltage as stored in register 0x02 3.35 V
J5: nBYP, Forced Bypass Selection
Placing a jumper across pins nBYP and ON ties the nBYP pin to GND and enables the pass-through
mode. Placing a jumper across pins nBYP and OFF ties the nBYP pin to VIN and enables auto DC/DC
boost mode.
Table 2. TPS61280 Mode of Operations
EN Input nBYP Input Device Status
LOW LOW The device is shut down in pass-through mode featuring a shutdown current down to ca. 2 μA typ. The
load current capability is limited (up to ca. 250 mA).
LOW HIGH The device is shut down and the output voltage is reduced to a minimum value (VIN – VOUT ≤3.6 V).
The device shutdown current is approximately 8.5 μA typ.
HIGH LOW The device is active in forced pass-through mode. The device supply current is approximately 15 μA typ.
from the battery. The device is short-circuit protected by a current limit of ca. 7300 mA.
HIGH HIGH The device is active in auto mode (dc/dc boost, pass-through). The device supply current is approximately
50 μA typ. from the battery.
J6: GPIO/PG, General Purpose In/Out and Power Good
This pin can either be configured as a input (mode selection) or as dual role input/open-drain output
(nRST/nFAULT) pin. Per default, the pin is configured as nRST/nFAULT input/output.
Pin GPIO/PG is connected to HIGH per default. This pin is tied to VIN via pull-Up resistor R5.
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J7: SCL Pull-Up Resistor
This header enables the possibility to apply the onboard pull-Up resistor R3 as well as to track the I²C
Clock signal on pin 2.
Placing a jumper across pins 1 and 2 ties SCL via resistor R3 to VIN. Per default, the USB-to-GPIO
Interface Adapter has a Pull-Up resistor applied. Therefore this Jumper is not fitted.
J8: SDA Pull-Up Resistor
This header enables the possibility to apply the onboard pull-Up resistor R4 as well as to track the I²C
Data signal on pin 2.
Placing a jumper across pins 1 and 2 ties SDA via resistor R4 to VIN. Per default, the USB-to-GPIO
Interface Adapter has a Pull-Up resistor applied. Therefore, this jumper is not fitted.
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www.ti.com TPS61280EVM Assembly Drawings and Layout
4 TPS61280EVM Assembly Drawings and Layout
Figure 2 through Figure 6 show the design of the TPS61280EVM-585 PCBs. The EVM has been designed
using a four-layer, 1-ounce copper-clad PCB with all components in an active area on the top side of the
board. Moving components to both sides of the PCB can offer additional size reduction for space-
constrained systems.
All layers are viewed from top side.
Figure 2. TPS61280EVM-585 Component Placement
Figure 3. TPS61280EVM-585 Top Copper
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Figure 4. TPS61280EVM-585 Inner Layer 1
Figure 5. TPS61280EVM-585 Inner Layer 2
Figure 6. TPS61280EVM-585 Bottom Copper
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Host
Computer
USB Cable
USB
Interface
Adapter
Green LED
Indicates
Power
10-Pin
Ribbon
Cable
EVM Board
USB Interface Adaptor Quick Connection Diagram
www.ti.com List of Materials
5 List of Materials
Table 3 lists the EVM components as configured according to the schematic shown in Figure 1.
Table 3. TPS61280 Bill of Materials
Count RefDes Value Description Size Part Number MFR
TPS61280 Solution Required Components
1 C5 1.5µF Capacitor, Ceramic, 6.3V +/- 20%, X5R 0402 GRM155R60J155ME80D MuRata
2 C6, C7 10µF Capacitor, Ceramic, 6.3V, +/- 20%, X5R 0603 GRM188R60J106ME84D MuRata
1 L1 470nH Inductor, Ferrite, 3.7A, 29mΩ2512 1239AS-H-R47M Toko
1 U1 TPS61280A IC, Step-Up DC/DC Converter with Pass-Through Mode 4x4 WCSP TPS61280AYFF Texas Instruments
TPS61280EVM-585 Evaluation Components
1 C1 150µF Capacitor, Tantalum, 6.3V +/-10%, 70mΩ7343-20 T495V157K006ATE070 Kemet
3 R3, R4, R5 2.2kΩResistor, +/-5%, 100mW 0603 RC0603JR-072K2L Yageo America
2 J1, J2 Header, 6x1, 100mil spacing TSW-106-07-G-S Samtec
6 J3, J4, J5, J6, Header, 2x1, 100mil spacing TSW-102-07-G-S Samtec
J7, J8
1 J9 Connector, 5x2, Shrouded, 100mil spacing 5103308-1 TE Connectivity
Software User Interface
Software Setup
The software is available at the TI.com website (SLVC543).
Download and unzip the file. Run setup.msi and follow the instructions appearing during the installation.
After the installation is completed, run the software by going to:
START -> All Programs -> Texas Instruments -> TPS61280 EVM -> TPS61280 EVM
Interface Hardware Setup
Connect the USB-to-GPIO adapter to your PC using the supplied USB cable. Connect the TPS61280EVM
connector J9 to the USB-to-GPIO adapter using the supplied 10-pin ribbon cable. The connectors on the
ribbon cable are keyed to prevent incorrect installation.
Figure 7 shows a quick adapter connection overview.
Figure 7. Quick Connection Overview
User Interface Operation
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List of Materials www.ti.com
Figure 8. User Interface of TPS61280EVM-585
Control Section
This section in the left, upper region reflects the User Control Registers. Here all adjustments can be done
on the user level.
5.0.1 Status Section
This section located in the left, lower region reflects the Status Register of the device.
Register View
The right part of the Interface shows a register-wise view of all parameters. This section reflects the
settings displayed in the left part as described in Section 5.0.1.
Here single registers can be read, or written to the device (if applicable).
Hardware Pull-Up Resistor Selection
Clicking on the SETUP Button in the top, a Pull-Up Resistor selection appears. Here the internal resistors
of the USB-to-GPIO interface can be switched ON/OFF. The status is displayed in the status bar.
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