Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Audio amplifier 1-channel (mono) Class AB VSSOP 8

LM4906, LM4906LDBD, LM4906MMBD

www.ti.com

SNAS191E –APRIL 2003–REVISED MAY 2013

LM4906 1W, Bypass-Capacitor-less Audio Amplifier with

Internal Selectable Gain

Check for Samples: LM4906, LM4906LDBD, LM4906MMBD

FEATURES

DESCRIPTION

The LM4906 is an audio power amplifier primarily

• Selectable Gain of 6dB (2V/V) or 12dB (4V/V)

designed for demanding applications in mobile

• No Output or PSRR Bypass Capacitors

phones and other portable communication device

Required

applications. It is capable of delivering 1W of

• Improved “Click and Pop” Suppression

continuous average power to an 8Ω BTL load with

less than 1% distortion (THD+N) from a +5V power

Circuitry

supply.

• Very Fast Turn on Time: 5ms (Typ)

The LM4906 is the first Texas Instruments Boomer

• Minimum External Components

Power Amplifier that does not require an external

• 2.6 - 5.5V Operation

PSRR bypass capacitor. The LM4906 also has an

• BTL Output Can Drive Capacitive Loads

internal selectable gain of either 6dB or 12dB. In

addition, no output coupling capacitors or bootstrap

• Ultra Low Current Shutdown Mode (SD Low)

capacitors are required which makes the LM4906

ideally suited for cell phone and other low voltage

APPLICATIONS

portable applications.

• Portable Computers

The LM4906 contains advanced pop and click

• Desktop Computers

circuitry that eliminates noise, which would otherwise

• Multimedia Monitors

occur during turn-on and turn-off transitions.

Boomer audio power amplifiers were designed

KEY SPECIFICATIONS

specifically to provide high quality output power with a

• Improved PSRR at 217Hz for +3V: 71 dB

minimal amount of external components. The

LM4906 features a low -power consumption

• Power Output at +5V, THD+N = 1%, 8Ω: 1.0 W

shutdown mode (the part is enabled by pulling the SD

(Typ)

pin high). Additionally, the LM4906 features an

• Power Output at +3V, THD+N = 1%, 8Ω: 390

internal thermal shutdown protection mechanism.

mW (Typ)

• Total Shutdown Power Supply Current: 0.1µA

(Typ)

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2All trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.

Summary of content (21 pages)

PAGE 1
LM4906, LM4906LDBD, LM4906MMBD www.ti.com SNAS191E – APRIL 2003 – REVISED MAY 2013 LM4906 1W, Bypass-Capacitor-less Audio Amplifier with Internal Selectable Gain Check for Samples: LM4906, LM4906LDBD, LM4906MMBD FEATURES DESCRIPTION • • The LM4906 is an audio power amplifier primarily designed for demanding applications in mobile phones and other portable communication device applications.
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LM4906, LM4906LDBD, LM4906MMBD SNAS191E – APRIL 2003 – REVISED MAY 2013 www.ti.com Typical Application Figure 1. Typical Audio Amplifier Application Circuit Connection Diagram Figure 2. VSSOP Package (Top View) See Package Number DGK Figure 3.
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LM4906, LM4906LDBD, LM4906MMBD www.ti.com SNAS191E – APRIL 2003 – REVISED MAY 2013 LM4906GR Pin Designation (continued) C4 VDD D1 No Connect D2 No Connect D3 VO1 D4 VDD Absolute Maximum Ratings (1) (2) Supply Voltage (3) 6.0V −65°C to +150°C Storage Temperature −0.3V to VDD +0.
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LM4906, LM4906LDBD, LM4906MMBD SNAS191E – APRIL 2003 – REVISED MAY 2013 www.ti.com Electrical Characteristics VDD = 5V (1) (2) The following specifications apply for the circuit shown in Figure 1, unless otherwise specified. Limits apply for TA = 25°C. Symbol Parameter Conditions IDD Quiescent Power Supply Current ISD Shutdown Current VOS Output Offset Voltage LM4906 Typical (3) Limit (4) (5) Units (Limits) VIN = 0V, Io = 0A, No Load 3.
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LM4906, LM4906LDBD, LM4906MMBD www.ti.com SNAS191E – APRIL 2003 – REVISED MAY 2013 Electrical Characteristics VDD = 3V (1) (2) The following specifications apply for the circuit shown in Figure 1, unless otherwise specified. Limits apply for TA = 25°C. Symbol Parameter LM4906 Conditions IDD Quiescent Power Supply Current ISD Shutdown Current VOS Output Offset Voltage Typical (3) Limit (4) (5) Units (Limits) VIN = 0V, Io = 0A, No Load 2.
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LM4906, LM4906LDBD, LM4906MMBD SNAS191E – APRIL 2003 – REVISED MAY 2013 www.ti.com Typical Performance Characteristics 6 THD+N vs Frequency VDD = 5V, RL = 8Ω, f = 1kHz, PWR = 500mW THD+N vs Frequency VDD = 3V, RL = 8Ω, f = 1kHz, PWR = 250mW Figure 4. Figure 5. THD+N vs Power Out VDD = 5V, RL = 8Ω, f = 1kHz THD+N vs Power Out VDD = 3V, RL = 8Ω, f = 1kHz Figure 6. Figure 7.
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LM4906, LM4906LDBD, LM4906MMBD www.ti.com SNAS191E – APRIL 2003 – REVISED MAY 2013 Typical Performance Characteristics (continued) Noise Floor VDD = 5V, RL = 8Ω 80kHz Bandwith, Input to GND Power Derating Curve Figure 10. Figure 11. Power Dissipation vs Output Power, VDD = 3V, RL = 8Ω Power Dissipation vs Output Power, VDD = 5V, RL = 8Ω 0.7 0.25 POWER DISSIPATION (mW) POWER DISSIPATION (mW) 0.6 0.20 0.15 0.10 0.5 0.4 0.3 0.2 0.05 0.1 0.0 0.0 0.2 0.4 0.6 0.8 1.0 1.
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LM4906, LM4906LDBD, LM4906MMBD SNAS191E – APRIL 2003 – REVISED MAY 2013 www.ti.com Typical Performance Characteristics (continued) Shutdown Hysteresis Voltage VDD = 3V, SD Mode = VDD (High) 3.5 Shutdown Hysteresis Voltage VDD = 3V, SD Mode = GND (Low) SUPPLY CURRENT (mA) 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.0 1.0 2.0 3.0 4.0 SHUTDOWN VOLTAGE (V) Figure 16. Figure 17. Output Power vs Supply Voltage, RL = 8Ω Output Power vs Supply Voltage, RL = 32Ω 600.0 2000 500.
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LM4906, LM4906LDBD, LM4906MMBD www.ti.com SNAS191E – APRIL 2003 – REVISED MAY 2013 Typical Performance Characteristics (continued) PSRR Distribution VDD = 5V, f = 1kHz, RL = 8Ω -80 -70 PSRR Distribution VDD = 5V, f = 217Hz, RL = 8Ω -60 -68 -75 (dBr) Figure 22. Figure 23. PSRR Distribution VDD = 3V, f = 1kHz, RL = 8Ω PSRR Distribution VDD = 3V, f = 217Hz, RL = 8Ω -85 -74 -62 -72 -80 (dBr) -63 (dBr) Figure 24. Copyright © 2003–2013, Texas Instruments Incorporated -61 (dBr) Figure 25.
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LM4906, LM4906LDBD, LM4906MMBD SNAS191E – APRIL 2003 – REVISED MAY 2013 www.ti.com APPLICATION INFORMATION BRIDGE CONFIGURATION EXPLANATION As shown in Figure 26, the LM4906 has two internal operational amplifiers. The first amplifier's gain is either 6dB or 12dB depending on the gain select input (Low = 6dB, High = 12dB). The second amplifier's gain is fixed by the two internal 20kΩ resistors.
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LM4906, LM4906LDBD, LM4906MMBD www.ti.com SNAS191E – APRIL 2003 – REVISED MAY 2013 TURNING ON THE LM4906 The power supply must first be applied before the application of an input signal to the device and the ramp time to VDD must be less than 4ms, otherwise the wake-up time of the device will be affected. After applying VDD, the LM4906 will turn-on after an initial minimum threshold input signal of 7mVRMS, resulting in a generated output differential signal.
PAGE 12
LM4906, LM4906LDBD, LM4906MMBD SNAS191E – APRIL 2003 – REVISED MAY 2013 www.ti.com The final design step is to address the bandwidth requirements which must be stated as a pair of −3dB frequency points. Five times away from a −3dB point is 0.17dB down from passband response which is better than the required ±0.25dB specified. fL = 100Hz / 5 = 20Hz fH = 20kHz * 5 = 100kHz As stated in the External Components Description section, Rin (20k) in conjunction with C2 create a highpass filter.
PAGE 13
LM4906, LM4906LDBD, LM4906MMBD www.ti.com SNAS191E – APRIL 2003 – REVISED MAY 2013 LM4906 VSSOP DEMO BOARD ARTWORK Figure 27. Top Layer Figure 28.
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LM4906, LM4906LDBD, LM4906MMBD SNAS191E – APRIL 2003 – REVISED MAY 2013 www.ti.com LM4906 LD DEMO BOARD ARTWORK Figure 29. Top Layer Figure 30.
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LM4906, LM4906LDBD, LM4906MMBD www.ti.com SNAS191E – APRIL 2003 – REVISED MAY 2013 Table 1. Mono LM4906 Reference Design Boards Bill of Material Part Description Quantity Reference Designator LM4906 Audio Amplifier 1 U1 Tantalum Capcitor, 1µF 1 C1 Ceramic Capacitor, 0.39µF 1 C2 Jumper Header Vertical Mount 2X1 0.
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LM4906, LM4906LDBD, LM4906MMBD SNAS191E – APRIL 2003 – REVISED MAY 2013 www.ti.com REVISION HISTORY Changes from Revision D (May 2013) to Revision E • 16 Page Changed layout of National Data Sheet to TI format ..........................................................................................................
PAGE 17
PACKAGE OPTION ADDENDUM www.ti.com 2-May-2013 PACKAGING INFORMATION Orderable Device Status (1) LM4906MM/NOPB ACTIVE Package Type Package Pins Package Drawing Qty VSSOP DGK 8 1000 Eco Plan Lead/Ball Finish (2) Green (RoHS & no Sb/Br) MSL Peak Temp Op Temp (°C) Top-Side Markings (3) CU SN Level-1-260C-UNLIM (4) -40 to 85 GA8 (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs.
PAGE 18
PACKAGE MATERIALS INFORMATION www.ti.com 8-May-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device LM4906MM/NOPB Package Package Pins Type Drawing VSSOP DGK 8 SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) 1000 178.0 12.4 Pack Materials-Page 1 5.3 B0 (mm) K0 (mm) P1 (mm) 3.4 1.4 8.0 W Pin1 (mm) Quadrant 12.
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PACKAGE MATERIALS INFORMATION www.ti.com 8-May-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM4906MM/NOPB VSSOP DGK 8 1000 210.0 185.0 35.
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