LM4872
Electrical Characteristics V
DD
= 2.6V
(Notes 1, 2, 8, 9)
The following specifications apply for V
DD
= 2.6V and 8Ω Load unless otherwise specified. Limits apply for T
A
=
25˚C. (Continued)
LM4872
Symbol
V
OS
P
0
THD+N
PSRR
Parameter
Output Offset Voltage
Output Power ( 8Ω )
Output Power ( 4Ω )
Total Harmonic Distortion+Noise
Power Supply Rejection Ratio
V
IN
= 0V
THD = 0.3% (max); f = 1 kHz THD
= 0.5% (max); f = 1 kHz
P
o
= 0.25 Wrms; A
VD
= 2; 20 Hz
≤
f
≤
20 kHz
V
DD
= 2.5V to 2.7V
Conditions
Typical
5
0.25
0.5
0.25
65
Limit
Units
(Limits)
mV (max)
W
W
%
dB
Note 1:
All voltages are measured with respect to the ground pin, unless otherwise specified.
Note 2:
Absolute Maximum Ratings
indicate limits beyond which damage to the device may occur.
Operating Ratings
indicate conditions for which the device is
functional, but do not guarantee specific performance limits.
Electrical Characteristics
state DC and AC electrical specifications under particular test conditions which
guarantee 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 3:
The maximum power dissipation must be derated at elevated temperatures and is dictated by T
JMAX
,
θ
JA
, and the ambient temperature T
A
. The maximum
allowable power dissipation is P
DMAX
= (T
JMAX
–T
A
)/θ
JA
or the number given in Absolute Maximum Ratings, whichever is lower. For the LM4872, T
JMAX
= 150˚C.
The typical junction-to-ambient thermal resistance is 150˚C/W.
Note 4:
Human body model, 100 pF discharged through a 1.5 kΩ resistor.
Note 5:
Machine Model, 220 pF–240 pF discharged through all pins.
Note 6:
Typicals are measured at 25˚C and represent the parametric norm.
Note 7:
Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).
Note 8:
Low Voltage Circuit - See Fig. 4
Note 9:
Shutdown current is measured in a Normal Room Environment. Exposure to direct sunlight will increase I
SD
by a maximum of 2µA.
External Components Description
1)
Components
1.
2.
R
i
C
i
Functional Description
Inverting input resistance which sets the closed-loop gain in conjunction with R
f
. This resistor also forms a
high pass filter with C
i
at f
C
= 1/(2π R
i
C
i
).
Input coupling capacitor which blocks the DC voltage at the amplifiers input terminals. Also creates a
highpass filter with R
i
at f
c
= 1/(2π R
i
C
i
). Refer to the section,
Proper Selection of External Components,
for an explanation of how to determine the value of C
i
.
Feedback resistance which sets the closed-loop gain in conjunction with R
i
.
Supply bypass capacitor which provides power supply filtering. Refer to the
Power Supply Bypassing
section for information concerning proper placement and selection of the supply bypass capacitor.
Bypass pin capacitor which provides half-supply filtering. Refer to the section,
Proper Selection of External
Components,
for information concerning proper placement and selection of C
B
.
3.
4.
5.
R
f
C
S
C
B
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