Datasheet

TS4990 Application information
Doc ID 9309 Rev 13 19/33
The graph in Figure 60 shows an example of C
in
and C
feed
influence.
Figure 60. Frequency response gain vs. C
in
and C
feed
4.4 Power dissipation and efficiency
Hypotheses:
● Load voltage and current are sinusoidal (V
out
and I
out
).
● Supply voltage is a pure DC source (V
CC
).
The load can be expressed as:
and
and
Therefore, the average current delivered by the supply voltage is:
The power delivered by the supply voltage is:
10 100 1000 10000
-25
-20
-15
-10
-5
0
5
10
Rin = Rfeed = 22kΩ
Tamb = 25°C
Cfeed = 2.2nF
Cfeed = 680pF
Cfeed = 330pF
Cin = 470nF
Cin = 82nF
Cin = 22nF
Gain (dB)
Frequency (Hz)
V
out
= V
PEAK
sinωt (V)
I
out
=
V
out
R
L
-------------
(A)
P
out
=
V
PEAK
2
2R
L
------------------------- (W)
I
CC
AVG
= 2
V
PEAK
πR
L
---------------------- (A)
P
supply
V
CC
I
CC
AVG
(W)⋅=