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LM4873 Datasheet, PDF (4/19 Pages) National Semiconductor (TI) – Dual 2.1W Audio Amplifier Plus Stereo Headphone Function
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Electrical Characteristics for Bridged-Mode Operation (Notes 3, 4) (Continued)
The following specifications apply for VDD= 5V unless otherwise specified. Limits apply for TA= 25˚C.
Symbol
Parameter
Conditions
LM4873
Typical Limit
(Note
17)
(Note
18)
THD+N Total Harmonic Distortion+Noise 20 Hz ≤ f ≤ 20 kHz, AVD = 2
0.3
LM4873MTE-1, RL = 4Ω, PO = 2W
LM4873, RL = 8Ω, PO = 1W
0.3
PSRR Power Supply Rejection Ratio
VDD = 5V, VRIPPLE = 200 mVRMS, RL = 8Ω,
67
CB = 1.0 µF
XTALK
Channel Separation
f = 1 kHz, CB = 1.0 µF
80
SNR
Signal To Noise Ratio
VDD = 5V, PO = 1.1W, RL = 8Ω
97
Units
(Limits)
%
dB
dB
dB
Electrical Characteristics for Single-Ended Operation (Notes 3, 4)
The following specifications apply for VDD= 5V unless otherwise specified. Limits apply for TA= 25˚C.
Symbol
Parameter
Conditions
LM4873
Typical Limit
Units
(Limits)
(Note
17)
(Note
18)
VOS
PO
THD+N
PSRR
Output Offset Voltage
Output Power
Total Harmonic Distortion+Noise
Power Supply Rejection Ratio
VIN = 0V
THD = 0.5%, f = 1 kHz, RL = 32Ω
THD+N = 1%, f = 1 kHz, RL = 8Ω
THD+N = 10%, f = 1 kHz, RL = 8Ω
AV = −1, PO = 75 mW, 20 Hz ≤ f ≤ 20 kHz,
RL = 32Ω
CB = 1.0 µF, VRIPPLE = 200 mV RMS,
f = 1 kHz
5
50
mV (max)
85
75
mW (min)
340
mW
440
mW
0.2
%
52
dB
XTALK Channel Separation
f = 1 kHz, CB = 1.0 µF
60
dB
SNR
Signal To Noise Ratio
VDD = 5V, PO = 340mW, RL = 8Ω
94
dB
Note 3: All voltages are measured with respect to the ground pins, 2, 7, and 15, unless otherwise specified.
Note 4: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is func-
tional, but do not guarantee specific performance limits. Electrical Characteristics state DC and AC electrical specifications under particular test conditions which guar-
antee specific performance limits. This assumes that the device is within the Operating Ratings. Specifications are not guaranteed for parameters where no limit is
given, however, the typical value is a good indication of device performance.
Note 5: The θJA given is for an MXA20A package whose exposed-DAP is soldered to an exposed 2in2 piece of 1 ounce printed circuit board copper.
Note 6: The θJA given is for an MXA20A package whose exposed-DAP is soldered to an exposed 1in2 piece of 1 ounce printed circuit board copper.
Note 7: The θJA given is for an MXA20A package whose exposed-DAP is not soldered to any copper.
Note 8: The θJA given is for an MXA28A package whose exposed-DAP is soldered to an exposed 2in2 piece of 1 ounce printed circuit board copper.
Note 9: The θJA given is for an MXA28A package whose exposed-DAP is soldered to an exposed 1in2 piece of 1 ounce printed circuit board copper.
Note 10: The θJA given is for an MXA28A package whose exposed-DAP is not soldered to any copper.
Note 11: When driving 3Ω loads from a 5V supply, the LM4873MTE or LM4873MTE-1 must be mounted to the circuit board and forced-air cooled (450 linear-feet
per minute).
Note 12: When driving 4Ω loads from a 5V supply, the LM4873MTE or LM4873MTE-1 must be mounted to the circuit board.
Note 13: Output power is measured at the device terminals.
Note 14: The maximum power dissipation must be derated at elevated temperatures and is dictated by TJMAX, θ JA, and the ambient temperature TA. The maximum
allowable power dissipation is PDMAX = (TJMAX − T A)/θJA. For the LM4873, TJMAX = 150˚C. For the θJAs for different packages, please see the Application Informa-
tion section or the Absolute Maximum Ratings section.
Note 15: Human body model, 100 pF discharged through a 1.5 kΩ resistor.
Note 16: Machine model, 220 pF–240 pF discharged through all pins.
Note 17: Typicals are measured at 25˚C and represent the parametric norm.
Note 18: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).
Note 19: The quiescent power supply current depends on the offset voltage when a practical load is connected to the amplifier.
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