LM1036N National Semiconductor, LM1036N Datasheet - Page 6

• Manufacturer Part Number: LM1036N
• Description: Audio Power Amplifier IC
• Manufacturer: National Semiconductor

Specifications of LM1036N

• No. Of Channels: 2
• Amplifier Case Style: DIP
• No. Of Pins: 20
• Peak Reflow Compatible (260 C): No
• Leaded Process Compatible: No
• Mounting Type: Through Hole
• Package / Case: 20-DIP
• No. Of Amplifiers: 2
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

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Applications Information
Figure 4 shows the effect of changing C
site direction to C
ranges. The various results corresponding to the different C
and C
lar emphasis to, for example, the bass control. The particular
case with C
Restriction of Tone Control Action at High or Low
Frequencies
It may be desired in some applications to level off the tone
responses above or below certain frequencies for example
to reduce high frequence noise.
This may be achieved for the treble response by including a
resistor in series with C
dB less than the standard circuit when R = X
A similar effect may be obtained for the bass response by re-
ducing the value of the AC bypass capacitors on pins 5
(channel 1) and 16 (channel 2). The internal resistance at
these pins is 1.3 k
mately 3 dB less with X
modified response curves is shown in Figure 6 . The input
coupling capacitors may also modify the low frequency re-
sponse.
It will be seen from Figure 2 and Figure 3 that modifying C
and C
ing the tone control extremes and this may be utilized, with
or without additional modification as outlined above, for the
most suitable tone control range and response shape.
Other Advantages of DC Controls
The DC controls make the addition of other features easy to
arrange. For example, the negative-going peaks of the out-
put amplifiers may be detected below a certain level, and
used to bias back the bass control from a high boost condi-
tion, to prevent overloading the speaker with low frequency
components.
LOUDNESS CONTROL
The loudness control is achieved through control of the tone
sections by the voltage applied to pin 7; therefore, the tone
and loudness functions are not independent. There is nor-
mally 1 dB more bass than treble boost (40 Hz–16 kHz) with
loudness control in the standard circuit. If a greater differ-
ence is desired, it is necessary to introduce an offset by
means of C
ranges.
Figure 7 shows the typical loudness curves obtained in the
standard application circuit at various volume levels
(C
b
= 0.39 µF).
b
b
values may be mixed if it is required to give a particu-
for greater control range also has the effect of flatten-
t
b
or C
/2, C
b
t
/2, 2C
t
or by changing the nominal control voltage
is illustrated in Figure 5 .
and the bass boost/cut will be approxi-
b
t
C
. The treble boost and cut will be 3
respectively giving reduced control
at this value. An example of such
t
and C
(Continued)
C
.
b
in the oppo-
t
t
6
Figure 8 and Figure 9 illustrate the loudness characteristics
obtained with C
FIGURE 4. Tone Characteristic (Gain vs Frequency)
FIGURE 5. Tone Characteristic (Gain vs Frequency)
FIGURE 6. Tone Characteristic (Gain vs Frequency)
FIGURE 7. Loudness Compensated Volume
b
changed to C
Characteristic
b
/2 and C
DS005142-10
DS005142-9
b
/4 respectively, C
DS005142-7
DS005142-8
t