Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Audio amplifier 2-channel (stereo) Class AB TO 263 9

LM4755

www.ti.com

SNAS010E –FEBRUARY 1999–REVISED APRIL 2013

LM4755 Stereo 11W Audio Power Amplifier with Mute

Check for Samples: LM4755

FEATURES

DESCRIPTION

The LM4755 is a stereo audio amplifier capable of

• Drives 4Ω and 8Ω Loads

delivering 11W per channel of continuous average

• Integrated Mute Function

output power to a 4Ω load or 7W per channel into 8Ω

• Internal Gain Resistors

using a single 24V supply at 10% THD+N. The

internal mute circuit and pre-set gain resistors provide

• Minimal External Components Needed

for a very economical design solution.

• Single Supply Operation

Output power specifications at both 20V and 24V

• Internal Current Limiting and Thermal

supplies and low external component count offer high

Protection

value to consumer electronic manufacturers for

• Compact 9-lead TO-220 Package

stereo TV and compact stereo applications. The

• Wide Supply Range 9V - 40V

LM4755 is specifically designed for single supply

operation.

APPLICATIONS

• Stereos TVs

• Compact Stereos

• Mini Component Stereos

KEY SPECIFICATIONS

• Output Power at 10% THD with 1kHz into 4Ω at

= 24V 11 W (typ)

• Output Power at 10% THD with 1kHz into 8Ω at

= 24V 7 W (typ)

• Closed Loop Gain 34 dB (typ)

• P

at 10% THD+N @ 1kHz into 4Ω Single-

Ended DDPAK Package at V

=12V 2.5 W (typ)

• P

at 10% THD+N @ 1kHz into 8Ω Bridged

DDPAK Package at V

=12V 5 W (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 (29 pages)

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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 LM4755 Stereo 11W Audio Power Amplifier with Mute Check for Samples: LM4755 FEATURES DESCRIPTION • • • • • • The LM4755 is a stereo audio amplifier capable of delivering 11W per channel of continuous average output power to a 4Ω load or 7W per channel into 8Ω using a single 24V supply at 10% THD+N. The internal mute circuit and pre-set gain resistors provide for a very economical design solution.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com TYPICAL APPLICATION Figure 1.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 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. ABSOLUTE MAXIMUM RATINGS (1) (2) (3) (4) Supply Voltage 40V Input Voltage ±0.7V Input Voltage at Output Pins (5) GND -0.4V Output Current Internally Limited Power Dissipation (6) 62.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com ELECTRICAL CHARACTERISTICS (continued) The following specifications apply to each channel with VCC = 24V, TA = 25°C unless otherwise specified. Symbol PSRR Parameter Power Supply Rejection Ratio Conditions See Apps. Circuit (Figure 1) LM4755 Typical (1) Limit 50 Units (Limits) dB f = 120 Hz, VO = 1 mVrms VODV Differential DC Output Offset Voltage VIN = 0V 0.09 0.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 TEST CIRCUIT Figure 3.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com SYSTEM APPLICATION CIRCUIT Figure 4. Circuit for External Components Description EXTERNAL COMPONENTS DESCRIPTION Components 6 Function Description 1, 2 CS Provides power supply filtering and bypassing. 3, 4 RSN Works with CSN to stabilize the output stage from high frequency oscillations. 5, 6 CSN Works with RSN to stabilize the output stage from high frequency oscillations.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 TYPICAL PERFORMANCE CHARACTERISTICS Typicals are measured at 25°C and represent the parametric norm. THD+N vs Output Power THD+N vs Output Power Figure 5. Figure 6. THD+N vs Output Power THD+N vs Output Power Figure 7. Figure 8. THD+N vs Output Power THD+N vs Output Power Figure 9. Figure 10.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com TYPICAL PERFORMANCE CHARACTERISTICS (continued) Typicals are measured at 25°C and represent the parametric norm. 8 THD+N vs Output Power THD+N vs Output Power Figure 11. Figure 12. THD+N vs Output Power THD+N vs Output Power Figure 13. Figure 14. THD+N vs Output Power THD+N vs Output Power Figure 15. Figure 16.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 TYPICAL PERFORMANCE CHARACTERISTICS (continued) Typicals are measured at 25°C and represent the parametric norm. THD+N vs Output Power THD+N vs Output Power Figure 17. Figure 18. THD+N vs Output Power THD+N vs Output Power Figure 19. Figure 20. THD+N vs Output Power THD+N vs Output Power Figure 21. Figure 22.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com TYPICAL PERFORMANCE CHARACTERISTICS (continued) Typicals are measured at 25°C and represent the parametric norm. 10 THD+N vs Output Power THD+N vs Output Power Figure 23. Figure 24. THD+N vs Output Power THD+N vs Output Power Figure 25. Figure 26. THD+N vs Output Power THD+N vs Output Power Figure 27. Figure 28.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 TYPICAL PERFORMANCE CHARACTERISTICS (continued) Typicals are measured at 25°C and represent the parametric norm. Output Power vs Supply Voltage Output Power vs Supply Voltage Figure 29. Figure 30. Frequency Response THD+N vs Frequency Figure 31. Figure 32. THD+N vs Frequency Frequency Response Figure 33. Figure 34.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com TYPICAL PERFORMANCE CHARACTERISTICS (continued) Typicals are measured at 25°C and represent the parametric norm. 12 Channel Separation PSRR vs Frequency Figure 35. Figure 36. Supply Current vs Supply Voltage Power Derating Curve Figure 37. Figure 38. Power Dissipation vs Output Power Power Dissipation vs Output Power Figure 39. Figure 40.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 TYPICAL PERFORMANCE CHARACTERISTICS (continued) Typicals are measured at 25°C and represent the parametric norm. Power Dissipation vs Output Power Power Dissipation vs Output Power Figure 41. Figure 42.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com APPLICATION INFORMATION The LM4755 contains circuitry to pull down the bias line internally, effectively shutting down the input stage. An external R-C should be used to adjust the timing of the pull-down.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 Figure 43. Bridge-Mode Application Figure 44.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com PREVENTING OSCILLATIONS With the integration of the feedback and bias resistors on-chip, the LM4755 fits into a very compact package. However, due to the close proximity of the non-inverting input pins to the corresponding output pins, the inputs should be AC terminated at all times. If the inputs are left floating, the amplifier will have a positive feedback path through high impedance coupling, resulting in a high frequency oscillation.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 The choice of a heatsink for a given application is dictated by several factors: the maximum power the IC needs to dissipate, the worst-case ambient temperature of the circuit, the junction-to-case thermal resistance, and the maximum junction temperature of the IC.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com HEATSINK DESIGN EXAMPLE Determine the system parameters: VS = 24V Operating Supply Voltage RL = 4Ω Minimum Load Impedance TA = 55°C Worst Case Ambient Temperature Device parameters from the datasheet: TJ = 150°C Maximum Junction Temperature θJC = 2°C/W Junction-to-Case Thermal Resistance Calculations: 2 • PDMAX = 2 • [VS2 / 2 • π2 • RL)] = (24V)2 / (2 • π2 • 4Ω) = 14.6W θSA ≤ [(TJ-TA) / PDMAX] - θJC–θCS = [ (150°C - 55°C) / 14.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 θSA < 100°C/3.7W − 2.0°C/W − 0.2°C/W = 24.8°C/W (11) Therefore the recommendation is to use 2.0 × 2.0 square inch of single-sided copper clad. Example 3: (Bridged Output) Given: TA=50°C TJ=150°C RL=8Ω VS=12V θJC=2°C/W Calculating PDMAX: PDMAX = 4[VCC2/(2π2RL)] = 4(12V)2/(2π2(8Ω)) = 3.65W (12) Calculating Heatsink Thermal Resistance: θSA < [(TJ − TA) / PDMAX] − θJC − θCS θSA < 100°C / 3.7W − 2.0°C/W − 0.2°C/W = 24.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com PC BOARD LAYOUT-COMPOSITE Figure 46.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 PC BOARD LAYOUT-SILK SCREEN Figure 47.
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LM4755 SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 www.ti.com PC BOARD LAYOUT-SOLDER SIDE Figure 48.
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LM4755 www.ti.com SNAS010E – FEBRUARY 1999 – REVISED APRIL 2013 REVISION HISTORY Changes from Revision D (April 2013) to Revision E • Page Changed layout of National Data Sheet to TI format ..........................................................................................................
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE OPTION ADDENDUM www.ti.com 30-Oct-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 8-Nov-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device LM4755TSX/NOPB Package Package Pins Type Drawing SPQ DDPAK/ TO-263 500 KTW 9 Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) 330.0 24.4 Pack Materials-Page 1 10.75 B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant 14.85 5.0 16.0 24.
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PACKAGE MATERIALS INFORMATION www.ti.com 8-Nov-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM4755TSX/NOPB DDPAK/TO-263 KTW 9 500 367.0 367.0 45.
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MECHANICAL DATA KTW0009A TS9A (Rev B) BOTTOM SIDE OF PACKAGE www.ti.
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IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.