Application Report

SLAA492A – April 2011 – Revised April 2011

TLV320AIC32x4 Power Supply Sequencing

Jorge Arbona, Peter Pai, Sunil Rafeeque, Shridhar More, and Nitesh Kekre .............................

Portable Audio

ABSTRACT

The TLV320AIC32x4 is capable of multiple power supply configurations. Power can be applied externally to support multiple voltage levels as well as internal generation of the analog and digital supply. This document discusses proper supply sequencing for these configurations.

1

2

3

4

1

2

3

3

4

1

2

5

Contents

Introduction

External DV

DD

..................................................................................................................

2

and AV

DD

Power Supply Sequence

.....................................................................

2

Internal DLDO and ALDO Power Supply Sequence

...................................................................

5

References

...................................................................................................................

6

List of Figures

TLV320AIC32x4 Power Management Architecture

DV

DD and AV

DD

....................................................................

2

Externally Provided

.......................................................................................

3

DV

DD and AV

DD

DV

DD and AV

DD

Externally Provided, AV

DD

Together With DV

DD

.......................................................

4

Recommended Circuit to Avoid Headphone Pop

.......................................................................

5

Generated by Internal LDO

.............................................................................

6

List of Tables

Power Supply Timing Parameters

........................................................................................

3

Power Supply Timing Parameters

........................................................................................

4

Power Supply Timing Parameters

........................................................................................

6

SLAA492A – April 2011 – Revised April 2011

Submit Documentation Feedback

© 2011, Texas Instruments Incorporated

TLV320AIC32x4 Power Supply Sequencing 1

Introduction

1 Introduction

www.ti.com

This document is divided into two parts: external supply configurations and internal supply configurations.

The application report SLAA404 and the relevant product data sheet provide detailed information on power supply configurations. The TLV320AIC32x4 power management architecture is shown in

Figure 1

as a reference.

LDOin / HPV

DD

LDO_SELECT

DV

AV

DD

DD

IOV

DD

To I /O

Blocks

Digital

EN

LDO p1_r2_b7-6

Analog

LDO

EN p1_r2_b5-4 p1_r2_b0 p1_r1_b3

To Digital

Blocks

Analog Blocks p1_r2_b3 p1_r123_b2-0

Digital, I/O, etc.

p1_r10_b1-0 p1_r10_b3

To Analog

Blocks

HP / Line Output

Amps p1_r51_b3

MICBIAS

Generation p1_r51_b6 p1_r51_b5-4

AV

SS

MICBIAS

Figure 1. TLV320AIC32x4 Power Management Architecture

2 External DV

DD

and AV

DD

Power Supply Sequence

The recommended power sequence for this configuration is to provide all supplies simultaneously. A typical configuration in such a case is to use a single 1.8-V supply for IOV

DD

, DV

DD

, LDOin, and AV

DD

.

Another alternative is to separate analog and digital supplies. This is useful to improve the efficiency of the digital rails by using a dc/dc converter, while keeping the AV regulator (LDO). This LDO can be external or internal.

DD supply clean by using a low-dropout

The LDOin supply can be sourced by an external supply of 1.9 V to 3.6 V to allow a higher signal swing at the headphone and line-out amplifiers, as well as to provide a wider range of MICBIAS supply options and output common-mode voltage. In the case where a 1.8-V rail is sufficient for output swing, LDOin must be tied to AV

DD

.

2 TLV320AIC32x4 Power Supply Sequencing

© 2011, Texas Instruments Incorporated

SLAA492A – April 2011 – Revised April 2011

Submit Documentation Feedback

www.ti.com

External DV

DD and AV

DD

Power Supply Sequence

Figure 2

shows a timing diagram for the case where all supplies are provided separately. In such a case, the depicted sequence must be used. The dashed lines marked in blue color represent an internally supplied voltage.

IOVDD t

I-D

DVDD t

D-L

LDOin t

L-A

AVDD t

D-R

RESET

Figure 2. DV

DD and AV

DD

Externally Provided

IOV

DD

AV

DD must be provided first. Because, by default, DV ramps up to the DV

DD voltage once DV

DD

DD is weakly connected to AV

DD is provided at approximately 5 × 10 k Ω by a 10-k

× C

AVDD

Ω resistor,

, where

C

AVDD is the A

VDD

Parameter t

D-L decoupling capacitor. For C allows AV

DD

AVDD

= 1 µF, the charging time is approximately 50 ms.

to be stable before HPVDD is provided, which prevents power-on pop on the headphone amplifiers. Immediately after DV

DD is provided, the LDOin supply ramps to ~1.5 V. To prevent high currents from DVDD to LDOin, the LDOin supply cannot be externally driven low by the external power source. This means that the external power source must be either high impedance or have a weak pulldown before being enabled. After RESET is released (or a software reset is performed), no register writes must be performed within 1 ms.

PARAMETER t

I-D t

D-L

MIN

0

5×10k×C

AVDD t

L-A t

D-R

0

10 ns

Table 1. Power Supply Timing Parameters

MAX TYP

0

5×10k×C

AVDD

0

10 ns

COMMENTS

Time between IOVDD is provided and DV

DD is provided.

Time between DV

DD is provided and LDOin is provided. AV

DD must be internally present before LDOin to prevent pop at headphone outputs.

Time between LDOin is provided and AV

DD is externally provided.

Time between DV

DD

(and IOVDD) is provided and reset can be released.

SLAA492A – April 2011 – Revised April 2011

Submit Documentation Feedback

© 2011, Texas Instruments Incorporated

TLV320AIC32x4 Power Supply Sequencing 3

External DV

DD and AV

DD

Power Supply Sequence www.ti.com

AV

DD can also be externally supplied at the same time as DV

DD

. This is shown in

Figure 3 . The dashed

line marked in blue color represents an internally supplied voltage.

IOVDD t

I-D

DVDD t

D-L

LDOin

AVDD t

D-R

RESET

Figure 3. DV

DD and AV

DD

Externally Provided, AV

DD

Together With DV

DD

To prevent high currents from DV

DD to LDOin, the LDOin supply cannot be externally driven low by the external power source. This means that the external power source must be either high impedance or have a weak pulldown before being enabled.

After RESET is released (or a software reset is performed), no register writes must be performed within 1 ms.

PARAMETER t

I-D t

D-L t

D-R

MIN

0

0

10 ns

Table 2. Power Supply Timing Parameters

MAX TYP

0

0

10 ns

COMMENTS

Time between IOVDD is provided and DV

DD

(and AV

DD

) is provided.

Time between DV

DD

(and AV

DD

) is provided and LDOin is provided.

Time between DV

DD

(and IOVDD) is provided and reset can be released.

4 TLV320AIC32x4 Power Supply Sequencing

© 2011, Texas Instruments Incorporated

SLAA492A – April 2011 – Revised April 2011

Submit Documentation Feedback

www.ti.com

3 Internal DLDO and ALDO Power Supply Sequence

Internal DLDO and ALDO Power Supply Sequence

Generating DV

DD and AV

DD internally is a common configuration for systems where a single 3.3-V supply is used. The DLDO is enabled by tying the LDO_SELECT pin to the IOVDD supply. As soon as IOVDD and LDOin are provided, DV

DD ramps to a nominal 1.72 V. At the same time, the AV

DD pin ramps up slower (5 × 10 k Ω × C

AVDD

) which might result in a pop in the headphone output amplifiers if C

AVDD is initially discharged. This pop can be avoided by adding a Schottky diode between DV shown in

Figure 4

DD and AV

DD

. Note that, in this configuration, ALDO mode must be chosen such that AV

DD pins as voltage is higher than or equal to DV

DD voltage. For example, ALDO can be configured as 1.77 V and DLDO as 1.77

V, or ALDO as 1.77 V and DLDO as 1.72 V.

DLDO p1_r1_b3

ALDO

DVDD

C DVDD

AVDD

C AVDD

Figure 4. Recommended Circuit to Avoid Headphone Pop

If the internal headphone amplifiers are connected to an external amplifier with mute or shutdown capabilities, it is unnecessary to add a diode. The purpose of this diode is to force the AV close to the DV

DD voltage at the same time and rate as LDOin is provided.

DD pin to ramp

SLAA492A – April 2011 – Revised April 2011

Submit Documentation Feedback

© 2011, Texas Instruments Incorporated

TLV320AIC32x4 Power Supply Sequencing 5

References www.ti.com

Figure 5

shows the timing diagram for the case where DV

DD and an external Schottky diode is placed between DV

DD and AV and AV

DD

DD are supplied by the internal LDOs

. The dashed line marked in blue color illustrates the voltage supplied through the external diode. The lines marked in red color illustrate a voltage generated by the internal LDOs.

IOVDD

DVDD

4

t

I-L

LDOin t

R-A

AVDD t

D-R

RESET

Figure 5. DV

DD and AV

DD

Generated by Internal LDO

As previously mentioned, if the internal headphone amplifiers are connected to an external amplifier with mute or shutdown capabilities, an external diode is not required. For such a case, AV approximately 5 × 10 k Ω × C

AVDD

.

DD ramps to DV

DD in

PARAMETER t

I-D t

D-R t

R-A

MIN

0

10 ns

1 ms

Table 3. Power Supply Timing Parameters

MAX TYP

0

10 ns

1 ms

COMMENTS

Time between IOVDD is provided and LDOin is provided.

Time between DVDD (and IOVDD) is provided and reset can be released.

Time between RESET is released and ALDO is powered. No registers must be written for 1 ms after a reset is performed (hardware or software).

References

1. Design and Configuration Guide for the TLV320AI3204 and TLV320AIC3254 Audio Codecs application report ( SLAA404 )

2. TLV320AIC3254, Ultra Low Power Stereo Audio Codec With Embedded miniDSP data sheet

( SLAS549 )

3. TLV320AIC3204, Ultra Low Power. Stereo Audio Codec data sheet ( SLOS602 )

6 TLV320AIC32x4 Power Supply Sequencing

© 2011, Texas Instruments Incorporated

SLAA492A – April 2011 – Revised April 2011

Submit Documentation Feedback

IMPORTANT NOTICE

Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.

TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed.

TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and applications using TI components. To minimize the risks associated with customer products and applications, customers should provide adequate design and operating safeguards.

TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information published by TI regarding third-party products or services does not constitute a license from TI to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI.

Reproduction of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional restrictions.

Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.

TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would reasonably be expected to cause severe personal injury or death, unless officers of the parties have executed an agreement specifically governing such use. Buyers represent that they have all necessary expertise in the safety and regulatory ramifications of their applications, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products and any use of TI products in such safety-critical applications, notwithstanding any applications-related information or support that may be provided by TI. Further, Buyers must fully indemnify TI and its representatives against any damages arising out of the use of TI products in such safety-critical applications.

TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products are specifically designated by TI as military-grade or "enhanced plastic." Only products designated by TI as military-grade meet military specifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is solely at the Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in connection with such use.

TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products are designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any non-designated products in automotive applications, TI will not be responsible for any failure to meet such requirements.

Following are URLs where you can obtain information on other Texas Instruments products and application solutions:

Products

Audio

Amplifiers

Data Converters

DLP® Products

DSP

Clocks and Timers

Interface

Logic

Power Mgmt www.ti.com/audio amplifier.ti.com

dataconverter.ti.com

www.dlp.com

dsp.ti.com

www.ti.com/clocks interface.ti.com

logic.ti.com

power.ti.com

Microcontrollers

RFID microcontroller.ti.com

www.ti-rfid.com

RF/IF and ZigBee® Solutions www.ti.com/lprf

Applications

Communications and Telecom www.ti.com/communications

Computers and Peripherals

Consumer Electronics

Energy and Lighting

Industrial www.ti.com/computers www.ti.com/consumer-apps

Medical

Transportation and

Automotive www.ti.com/medical

Security www.ti.com/security

Space, Avionics and Defense www.ti.com/space-avionics-defense www.ti.com/automotive

Video and Imaging

Wireless

TI E2E Community Home Page www.ti.com/energy www.ti.com/industrial www.ti.com/video www.ti.com/wireless-apps e2e.ti.com

Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265

Copyright © 2011, Texas Instruments Incorporated