Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Audio amplifier Headphones (2-channel, stereo) Class AB VSSOP 10

LM4911, LM4911Q

www.ti.com

SNAS152M –MAY 2004–REVISED JUNE 2011

LM4911/LM4911Q Stereo 40mW Low Noise Headphone

Amplifier with Selectable Capacitive Coupled or OCL Output

Check for Samples: LM4911, LM4911Q

FEATURES

KEY SPECIFICATIONS

• OCL or Capacitively Coupled Outputs (Patent

• PSRR at 217Hz and 1kHz 65 dB (typ)

Pending)

• Output Power at 1kHz with V

= 2.4V,

• External Gain-Setting Capability 1% THD+N into a 16Ω Load 25 mW (typ)

• Available in Space-Saving VSSOP and WSON • Output Power at 1kHz with V

= 3V,

Packages 1% THD+N into a 16Ω Load 40 mW (typ)

• Ultra Low Current Shutdown Mode • Shutdown Current 2.0 µA (max)

• Mute Mode Allows Fast Turn-on (1ms) with • Output Voltage Change on Release from

Less Than 1mV Change on Outputs Shutdown V

= 2.4V, R

= 16Ω (C-Coupled) 1

mV (max)

• 2V - 5.5V Operation

• Mute Current 100 µA (max)

• Ultra Low Noise

• LM4911QMM is an Automotive Grade Product

DESCRIPTION

that is AEC-Q100 Grade 2 Qualified.

The LM4911/LM4911Q is an stereo audio power

amplifier capable of delivering 40mW per channel of

APPLICATIONS

continuous average power into a 16Ω load or 25mW

• Portable CD Players

per channel into a 32Ω load at 1% THD+N from a 3V

power supply.

• PDAs

• Portable Electronics Devices

Boomer audio power amplifiers were designed

specifically to provide high quality output power with a

• Automotive

minimal amount of external components. Since the

LM4911/LM4911Q does not require bootstrap

capacitors or snubber networks, it is optimally suited

for low-power portable systems. In addition, the

LM4911/LM4911Q may be configured for either

single-ended capacitively coupled outputs or for OCL

outputs (patent pending).

Block Diagram

Figure 1. Block Diagram

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 (30 pages)

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LM4911, LM4911Q www.ti.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com DESCRIPTION (CONTINUED) The LM4911/LM4911Q features a low-power consumption shutdown mode and a power mute mode that allows for faster turn on time with less than 1mV voltage change at outputs on release. Additionally, the LM4911/LM4911Q features an internal thermal shutdown protection mechanism. The LM4911/LM4911Q is unity gain stable and may be configured with external gain-setting resistors.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 Connection Diagram Figure 4. VSSOP Package (Top View) See Package Number DGS0010A IN A 1 10 VDD SD 2 9 VoA MUTE 3 8 VoC BYPASS 4 7 VoB IN B 5 6 GND Figure 5. WSON Package (Top View) See Package Number NGY0010A These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com Electrical Characteristics VDD = 5.0V (1) (2) (3) The following specifications apply for VDD = 5V, RL = 16Ω, and CB = 4.7µF unless otherwise specified. Limits apply to TA = 25°C.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 Electrical Characteristics VDD = 3.3V (1) (2) (3) The following specifications apply for VDD = 3.3V, RL = 16Ω, and CB = 4.7µF unless otherwise specified. Limits apply to TA = 25°C. Symbol Parameter Conditions LM4911 LM4911Q Typ (4) Limit (5) Typ (4) Limit (5) Units (Limits) 1.5 3 1.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com Electrical Characteristics VDD = 3.0V (1) (2) (3) The following specifications apply for VDD = 3.0V, RL = 16Ω, and CB = 4.7µF unless otherwise specified. Limits apply to TA = 25°C. Symbol Parameter Conditions LM4911 LM4911Q Units (Limits) Typ (4) Limit (5) Typ (4) Limit (5) 1.5 3 1.5 3 mA (max) 4 mA (max) VIN = 0V, IO = 0A IDD Quiescent Current TA = +25°C TA = –40°C to +105°C ISD Shutdown Current VSHUTDOWN = GND 0.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 Electrical Characteristics VDD = 2.4V (1) (2) (3) The following specifications apply for VDD = 2.4V, RL = 16Ω, and CB = 4.7µF unless otherwise specified. Limits apply to TA = 25°C. Symbol Parameter Conditions LM4911 LM4911Q Units (Limits) Typ (4) Limit (5) Typ (4) Limit (5) 1.5 3 1.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com External Components Description (Figure 2) Components 8 Functional Description 1. RI Inverting input resistance which sets the closed-loop gain in conjunction with Rf. This resistor also forms a high-pass filter with Ci at fc = 1/(2πRiCi). 2. CI Input coupling capacitor which blocks the DC voltage at the amplifier's input terminals. Also creates a high-pass filter with Ri at fc = 1/(2πRiCi).
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 Typical Performance Characteristics THD+N vs Frequency THD+N vs Frequency Figure 6. Figure 7. THD+N vs Frequency THD+N vs Frequency Figure 8. Figure 9. THD+N vs Frequency THD+N vs Frequency Figure 10. Figure 11.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com Typical Performance Characteristics (continued) 10 THD+N vs Frequency THD+N vs Frequency Figure 12. Figure 13. THD+N vs Frequency THD+N vs Frequency Figure 14. Figure 15. THD+N vs Frequency THD+N vs Frequency Figure 16. Figure 17.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 Typical Performance Characteristics (continued) THD+N vs Output Power THD+N vs Output Power Figure 18. Figure 19. THD+N vs Output Power THD+N vs Output Power Figure 20. Figure 21. THD+N vs Output Power THD+N vs Output Power Figure 22. Figure 23.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com Typical Performance Characteristics (continued) 12 THD+N vs Output Power THD+N vs Output Power Figure 24. Figure 25. Output Resistance vs Load Resistance Output Power vs Supply Voltage Figure 26. Figure 27. Output Power vs Supply Voltage Output Power vs Supply Voltage Figure 28. Figure 29.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 Typical Performance Characteristics (continued) Output Power vs Supply Voltage Output Power vs Load Resistance Figure 30. Figure 31. Output Power vs Load Resistance Power Dissipation vs. Output Power Figure 32. Figure 33. Power Dissipation vs. Output Power Power Dissipation vs Output Power Figure 34. Figure 35.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com Typical Performance Characteristics (continued) 14 Channel Separation Channel Separation Figure 36. Figure 37. Channel Separation Channel Separation Figure 38. Figure 39. Channel Separation Channel Separation Figure 40. Figure 41.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 Typical Performance Characteristics (continued) Power Supply Rejection Ratio Power Supply Rejection Ratio Figure 42. Figure 43. Power Supply Rejection Ratio Power Supply Rejection Ratio Figure 44. Figure 45. Power Supply Rejection Ratio Power Supply Rejection Ratio Figure 46. Figure 47.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com Typical Performance Characteristics (continued) 16 Power Supply Rejection Ratio Power Supply Rejection Ratio Figure 48. Figure 49. Frequency Response vs Input Capacitor Size Frequency Response vs Input Capacitor Size Figure 50. Figure 51. Open Loop Frequency Response Supply Voltage vs Supply Current Figure 52. Figure 53.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 Typical Performance Characteristics (continued) Clipping Voltage vs Supply Voltage Noise Floor Figure 54. Figure 55. Shutdown Hysteresis Voltage, Vdd=5V Shutdown Hysteresis Voltage, Vdd=3V Figure 56. Figure 57. Power Derating Curve Figure 58.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com Typical Performance Characteristics LM4911/LM4911Q Specific Characteristics The NGY0010A package has its exposed-DAP soldered to an exposed 1.2in2 area of 1oz. Printed circuit board copper. 10 THD+N vs Frequency at VDD = 5V, RL = 16Ω PO = 100mW, OCL 10 5 5 THD+N vs Output Power at VDD = 5V, RL = 16Ω, OCL 2 1 1 0.5 THD + N (%) THD + N (%) 2 0.5 0.2 0.1 20kHz 20Hz 0.2 0.1 0.05 0.02 0.01 0.05 1kHz 0.005 0.02 0.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 APPLICATION INFORMATION AMPLIFIER CONFIGURATION EXPLANATION As shown in Figure 1, the LM4911/LM4911Q has three operational amplifiers internally. Two of the amplifier's have externally configurable gain while the other amplifier is internally fixed at the bias point acting as a unitygain buffer. The closed-loop gain of the two configurable amplifiers is set by selecting the ratio of Rf to Ri.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com The circuit shown in Figure 62 presents an applications solution to the problem of using different supply voltages with different turn-on times in a system with the LM4911/LM4911Q. This circuit shows the LM4911/LM4911Q with a 25-50kΩ pull-up resistor connected from the shutdown pin to VDD. The shutdown pin of the LM4911/LM4911Q is also being driven by an open drain output of an external microcontroller on a separate supply.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 POWER DISSIPATION Power dissipation is a major concern when using any power amplifier and must be thoroughly understood to ensure a successful design. When operating in capacitor-coupled mode, Equation 1 states the maximum power dissipation point for a single-ended amplifier operating at a given supply voltage and driving a specified output load.
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com MICRO POWER SHUTDOWN The voltage applied to the SHUTDOWN pin controls the LM4911/LM4911Q's shutdown function. Activate micropower shutdown by applying a logic-low voltage to the SHUTDOWN pin. When active, the LM4911/LM4911Q's micro-power shutdown feature turns off the amplifier's bias circuitry, reducing the supply current.
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LM4911, LM4911Q www.ti.com SNAS152M – MAY 2004 – REVISED JUNE 2011 OCL) and lasts for 100ms±25%. The timing of these transition periods relative to X1 and X2 is also shown in Figure 63. Mute should not be toggled during these time periods, but may be made during the shutdown transitions or any other time the part is in normal operation (while in cap-coupled mode - Mute is not valid in OCL mode).
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LM4911, LM4911Q SNAS152M – MAY 2004 – REVISED JUNE 2011 www.ti.com From Equation 3, the minimum AV is 0.89; use AV = 1. Since the desired input impedance is 20kΩ, and with a AV gain of 1, a ratio of 1:1 results from for Rf to Ri. The values are chosen with Ri = 20kΩ and Rf = 20kΩ. 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.
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE OPTION ADDENDUM www.ti.com 26-Aug-2013 In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
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PACKAGE MATERIALS INFORMATION www.ti.com 12-Aug-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant LM4911MM/NOPB VSSOP DGS 10 1000 178.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1 LM4911QMM/NOPB VSSOP DGS 10 1000 178.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1 LM4911QMMX/NOPB VSSOP DGS 10 3500 330.0 12.4 5.3 3.4 1.4 8.0 12.
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PACKAGE MATERIALS INFORMATION www.ti.com 12-Aug-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM4911MM/NOPB VSSOP DGS 10 1000 210.0 185.0 35.0 LM4911QMM/NOPB VSSOP DGS 10 1000 210.0 185.0 35.0 LM4911QMMX/NOPB VSSOP DGS 10 3500 367.0 367.0 35.
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