LM4841 National Semiconductor, LM4841 Datasheet
LM4841
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LM4841 Summary of contents
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... Note 1: When properly mounted to the circuit board, LM4841MH and LM4841LQ will deliver 2W into 4Ω. The LM4841MT will deliver 1.1W into 8Ω. See the Application Information section for LM4841MH usage information. Note 2: An LM4841MH that has been properly mounted to the circuit board and forced-air cooled will deliver 2.2W into 3Ω. Connection Diagrams ...
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... Connection Diagrams See NS Package Number LQA028AA for Exposed-DAP LLP Block Diagram www.national.com (Continued) LLP Package Top View Order Number LM4841LQ FIGURE 1. LM4841 Block Diagram 2 20028097 20028001 ...
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... A MAX 2.7V≤ 25˚C. A LM4841 Typical Limit (Note 14) (Note 15) 2.7 5 0.7 2 (Notes 7, 10) LM4841 Typical Limit (Note 14) (Note 15) ± 0.75 -75 -78 -78 www.national.com 3˚C/W 42˚C/W 20˚C/W 80˚C/W 2˚C/W 41˚C/W 54˚C/W 59˚C/W 93˚C/W ≤ 5.5V Units (Limits) V (min) V (max) mA (max) µ ...
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... Note 7: All voltages are measured with respect to the ground pins, unless otherwise specified. All specifications are tested using the typical application as shown in Figure 1. Note 8: When driving 3Ω loads from a 5V supply, LM4841MH and LM4841LQ must be mounted to the circuit board and forced-air cooled. Note 9: When driving 4Ω loads from a 5V supply, the LM4841MH and LM4841LQ must be mounted to the circuit board. ...
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Typical Application FIGURE 2. Typical Application Circuit ( Package Pinout ) Truth Table for Logic Inputs Headphone Gain Select Sense Off Off 1 X ...
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... LM4841MH/LQ THD+N vs Output Power LM4841MH/LQ THD+N vs Output Power LM4841MH/LQ Power Dissipation vs Output Power Note 17: These curves show the thermal dissipation ability of the LM4841MH/LQ at different ambient temperatures given these conditions: 2 500LFPM + 2in : The part is soldered to a 2in 2 2in on bottom: The part is soldered to a 2in ...
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Non-MH/LQ Specific Characteristics THD+N vs Frequency THD+N vs Frequency THD+N vs Frequency THD+N vs Frequency 20028057 THD+N vs Frequency 20028014 THD+N vs Frequency 20028016 7 20028058 20028015 20028017 www.national.com ...
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Non-MH/LQ Specific Characteristics THD+N vs Frequency THD+N vs Frequency THD+N vs Frequency www.national.com (Continued) THD+N vs Frequency 20028018 THD+N vs Frequency 20028020 THD+N vs Output Power 20028022 8 20028019 20028021 20028024 ...
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Non-MH/LQ Specific Characteristics THD+N vs Output Power THD+N vs Output Power THD+N vs Output Power (Continued) THD+N vs Output Power 20028025 THD+N vs Output Power 20028027 THD+N vs Output Power 20028029 9 20028026 20028028 20028030 www.national.com ...
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Non-MH/LQ Specific Characteristics THD+N vs Output Power THD+N vs Output Power THD+N vs Output Voltage Docking Station Pins www.national.com (Continued) THD+N vs Output Power 20028031 THD+N vs Output Power 20028033 THD+N vs Output Voltage Docking Station Pins 20028059 10 20028032 ...
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Typical Performance Characteristics Output Power vs Load Resistance Output Power vs Load Resistance Dropout Voltage 20028062 20028007 20028053 11 Output Power vs Load Resistance 20028006 Power Supply Rejection Ratio 20028039 Output Power vs Load Resistance 20028008 www.national.com ...
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Typical Performance Characteristics Volume Control Characteristics Power Dissipation vs Output Power Power Derating Curve www.national.com (Continued) 20028040 Bass Boost Characteristics 20028052 20028063 12 Power Dissipation vs Output Power 20028051 External Gain/ 20028061 Crosstalk 20028049 ...
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Typical Performance Characteristics Output Power vs Supply voltage Supply Current vs Supply Voltage (Continued) 20028054 20028009 13 Output Power vs Supply Voltage 20028056 www.national.com ...
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... A). The inverting output (Trace C) and the non-inverting output (Trace D) are applied across an 8Ω BTL Figure 3 shows the LM4841’s lack of transients in the differ- ential signal (Trace B) across a BTL 8Ω load. The LM4841’s active-high SHUTDOWN pin is driven by the logic signal shown in Trace A ...
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... BRIDGE CONFIGURATION EXPLANATION 2 As shown in Figure 2, the LM4841 output stage consists of (min) area is two pairs of operational amplifiers, forming a two-channel (channel A and channel B) stereo amplifier. (Though the following discusses channel A, it applies equally to channel B.) Figure 2 shows that the first amplifier’ ...
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... However, their presence does not eliminate the need for a local 1.0 µF tantalum bypass capacitance connected between the LM4841’s supply pins and ground. Do not substitute a ce- ramic capacitor for the tantalum. Doing so may cause oscil- )/θ ...
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... BYPASS pin. The gain of the internal amplifiers remains unity until the voltage on the BYPASS pin reaches 1/2 V voltage on the BYPASS pin is stable, the LM4841 is ready to be fully turned on. To turn the device on, the input signal must exceed 22mV threshold detect circuit that enables all appropriate output amplifiers after the 22mVrms limit is reached ...
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... MUTE pin. Even while muted, the DD LM4841 will amplify a system alert (beep) signal whose magnitude satisfies the BEEP DETECT circuitry. Applying 0V to the MUTE pin returns the LM4841 to normal, unmuted operation. Prevent unanticipated mute behavior by connect- ing the MUTE pin to V float. ...
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... FIGURE 6. The PCDN042 provides additional ESD protection beyond the 6500V shown in the Absolute Maximum Ratings for the AMP2A output GAIN SELECT FUNCTION (Bass Boost) The LM4841 features selectable gain, using either internal or external feedback resistors. Either set of feedback resistors set the gain of the output amplifiers. The voltage applied to the GAIN SELECT pin controls which gain is selected ...
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... DC voltage applied to the DC VOL CONTROL pin. www.national.com (Continued) 20028011 The LM4841 volume control consists of 31 steps that are individually selected by a variable DC voltage level on the volume control pin. The range of the steps, controlled by the . The BA DC voltage, are from 0dB - 78dB. Each gain step corre- sponds to a specific input voltage range, as shown in table 2, (on the following page ...
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Application Information VOLUME CONTROL TABLE ( Table 2 ) Gain Voltage Range (% of Vdd) (dB) Low High Recommended Low 0 77.5% 100.00% 100.000% -1 75.0% 78.5% 76.875% -2 72.5% 76.25% 74.375% -3 70.0% 73.75% 71.875% -4 67.5% 71.25% 69.375% ...
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... After satisfying the LM4841’s power dissipation require- ments, the minimum differential gain needed to achieve 1W dissipation in an 8Ω load is found using Equation (12). Thus, a minimum overall gain of 2.83 allows the LM4841’s to reach full output swing and maintain low noise and THD+N performance. ...
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... LM4841LQ Demo Board Artworks FIGURE 8. Top Layer SilkScreen FIGURE 9. Top Layer LQ 23 20028098 20028099 www.national.com ...
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... LM4841LQ Demo Board Artworks www.national.com (Continued) FIGURE 10. Bottom Layer LQ 24 200280A0 ...
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... Stereo Headphone Jack W/ Switch 41 131911368-002 Slide Switch 42 131911368-003 Potentiometer 43 131911368-004 RCA Jack 44 131911368-005 Banana Jack, Black 45 131911368-006 Banana Jack, Red Analog Audio LM4841LQ Eval Board Revision: A Bill of Material Qty Ref Designator CBA, CBB 3 C2, C3 CinA, CinB, Cinbeep CoutA, CoutB BYP ...
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... LM4841 MT & MH Demo Board Artworks www.national.com FIGURE 11. Top Layer SilkScreen FIGURE 12. Top Layer TSSOP 26 20028088 20028089 ...
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... LM4841 MT & MH Demo Board Artworks (Continued) FIGURE 13. Bottom Layer TSSOP FIGURE 14. Drill Drawing 27 20028090 20028091 www.national.com ...
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... Slide Switch 42 131911368-003 Potentiometer 43 131911368-004 RCA Jack 44 131911368-005 Banana Jack, Black 45 131911368-006 Banana Jack, Red www.national.com Analog Audio LM4841 MSOP Eval Board Assembly Part Number: 980011373-100 Revision: A Bill of Material Qty Ref Designator CBA, CBB 3 C2, C3 CinA, CinB, Cinbeep 3 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted NS Package Number LQA028A for Exposed-DAP LLP LLP Package Order Number LM4841LQ 29 www.national.com ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted (Continued) TSSOP Package Order Number LM4841MT NS Package Number MTC28 for TSSOP 30 ...
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... National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. inches (millimeters) unless otherwise noted (Continued) Exposed-DAP TSSOP Package Order Number LM4841MH 2. A critical component is any component of a life support device or system whose failure to perform ...