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User's Guide

SNVA235A – May 2007 – Revised April 2013

AN-1621 LP3972 USB Evaluation Board Rev B

1

General Description

The LP3972 Flex PMU is a complete power management IC designed for advanced processors. It
contains 5 low noise low dropout regulators, 3 DC/DC buck converters, a backup battery charger, real
time clock supply regulator [RTC], 2 GPO’s and high speed I

2

C serial interface to program individual

regulator output voltages as well as offer on/off control. This USB evaluation board features independent
USB powering, virtual voltmeter bank all in a compact demonstration platform.

2

Key Features

2.7V to 5.5V input voltage range

Programmable V

OUT

0.8 to 3.3 volts

Up to 95% efficiency

±3% output voltage accuracy

1.5A output current [bucks]

3

Applications

Personal Media Players

Smart Phones

PDA Phones

Digital Cameras

4

Evaluation Board/Kit Overview

The LP3972 Evaluation Board supports complete functional evaluation of the power management IC. The
functions of the chip are controlled by the I

2

C interface. The I

2

C interface on the rev B and later USB

boards are driven via a COP8 microprocessor which supports a connection via the USB port and offers
chip powering and virtual software voltage measurement of all regulators. In addition, the LP3972 can be
powered directly through the USB port for full function. If high current Buck testing is desired, an external
LI ION cell or PS capable of supplying 2 amps or more will need to be connected to the appropriate
connector.

The evaluation board/kit consists of:

LP3972 Flex_PMU device soldered down in RSB-40 pin 5X5 WQFN package

Full USB interface

LED LDO monitoring with current limit resistors [selectable]

External power LDO, Buck output and main battery/supply connectors offered in heavy duty turret pins
and solder pads

Socket for back-up battery

Users guide

Codeloader Software version 1.2.0.2 or greater [may be sent via email]

All trademarks are the property of their respective owners.

1

SNVA235A – May 2007 – Revised April 2013

AN-1621 LP3972 USB Evaluation Board Rev B

Submit Documentation Feedback

Copyright © 2007–2013, Texas Instruments Incorporated

Summary of Contents for LP3972

Page 1: ...ctions of the chip are controlled by the I2 C interface The I2 C interface on the rev B and later USB boards are driven via a COP8 microprocessor which supports a connection via the USB port and offer...

Page 2: ...s and LED monitoring Buck switcher ouputs and LED monitoring Power selection USB External External VCC Pads Turret pins Evaluation Board Kit Overview www ti com Figure 1 LP3972 Evaluation Board Versio...

Page 3: ...L I D I2 C Clock Input 23 FB2 Feedback Buck2 I A Buck Switcher 2 Feedback 24 nRST Out O D Reset Output 25 LDO_VOUT_5 O P LDO5 Output 26 VIN2 LDO 5 Only I P Battery Input Power for LDO5 27 VDDA I P Ana...

Page 4: ...priate rechargeable cell into supplied holder 13 Switches PKEY nTJ and SP are provided for use in normal evaluation mode 7 List of Components Item Qty Reference Value Pkg Manuf Part Number 1 5 C1 C21...

Page 5: ...lator SOT 23 5L Texas LP3984 2 0 Instruments 33 1 U6 Voltage Converter SOT 23 6 Texas LM2664M6 Instruments 34 1 J1 100 mil Header 2 pos Amp 1 2 4 103239 0 02 35 1 J2 USB Receptacle 4 pos FCI 61729 001...

Page 6: ...Output for nBATT Fault Outside Pin of Connector is Grd J6 2 Output for nREST Outside Pin of Connector is Grd J6 3 GPO 1 output Outside Pin of Connector is Grd J6 4 GPO 2 output Outside Pin of Connecto...

Page 7: ...the buck control an option for hold or go can be selected Note voltage will not change until the go selection is made The virtual voltmeters can be activated by selecting Poll Status after which an A...

Page 8: ...m 10 Layout Details Figure 4 Top Silkscreen Figure 5 Top Trace 8 AN 1621 LP3972 USB Evaluation Board Rev B SNVA235A May 2007 Revised April 2013 Submit Documentation Feedback Copyright 2007 2013 Texas...

Page 9: ...Details Figure 6 Bottom Trace Figure 7 Bottom Silkscreen 9 SNVA235A May 2007 Revised April 2013 AN 1621 LP3972 USB Evaluation Board Rev B Submit Documentation Feedback Copyright 2007 2013 Texas Instru...

Page 10: ...ww ti com Figure 8 Ground Plane Figure 9 Power Plane 10 AN 1621 LP3972 USB Evaluation Board Rev B SNVA235A May 2007 Revised April 2013 Submit Documentation Feedback Copyright 2007 2013 Texas Instrumen...

Page 11: ...ut Details Figure 10 Bare Board Component Locations 11 SNVA235A May 2007 Revised April 2013 AN 1621 LP3972 USB Evaluation Board Rev B Submit Documentation Feedback Copyright 2007 2013 Texas Instrument...

Page 12: ...P3972 Flex_PMU Evaluation Board Schematic Figure 11 LP3972 Flex_PMU Evaluation Board Schematic 12 AN 1621 LP3972 USB Evaluation Board Rev B SNVA235A May 2007 Revised April 2013 Submit Documentation Fe...

Page 13: ...sponsible for compliance with all legal regulatory and safety related requirements concerning its products and any use of TI components in its applications notwithstanding any applications related inf...

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