MAX9723BETE 데이터 시트보기 (PDF) - Maxim Integrated
부품명
상세내역
제조사
MAX9723BETE
Maxim Integrated
MAX9723BETE Datasheet PDF : 26 Pages
| |||
MAX9723
Stereo DirectDrive Headphone Amplifier
with BassMax, Volume Control, and I2C
MAX9723
R
R
AUDIO
INPUT
BassMax
ENABLE
OUT_
CA
RA
BB_
RB
Figure 12. Using BassMax to Increase MAX9723’s Maximum
Gain
Table 12. BassMax Gain Examples
(R1 = 47kΩ)
R2 (kΩ)
39
33
27
22
15
10
AV GAIN (dB)
20.6
15.1
11.3
8.8
5.7
3.7
Table 13. BassMax Pole and Zero
Examples for a Gain Boost of 8.8dB
(R1 = 47kΩ, R2 = 22kΩ)
C3 (nF)
100
82
68
56
47
22
10
fPOLE (Hz)
38
47
56
68
81
174
384
fZERO (Hz)
106
130
156
190
230
490
1060
FREQUENCY RESPONSE OF FIGURE 12
10
9
8
7
6
5
4
MAX9723A
3
CMD REGISTER
CODE = 0xFF
2
RA = 47kΩ
1
RB = 22kΩ
CA = 0.33mF
0
0.1
1
10 100 1k 10k
FREQUENCY (Hz)
Figure 13. Increasing the Maximum Gain Using BassMax
CA =
1
2 π fPOLE × (RA − RB )
Figure 13 shows the frequency response of the circuit in
Figure 12. With RA = 47kΩ, RB = 22kΩ, and CA = 0.33μF,
the passband gain is set to 8.8dB.
Layout and Grounding
Proper layout and grounding are essential for optimum
performance. Connect PGND and SGND together at a
single point on the PC board. Connect PVSS to SVSS
and bypass with a 1μF capacitor to PGND. Bypass VDD
to PGND with a 1μF capacitor. Place the power-supply
bypass capacitor and the charge-pump capacitors as
close to the MAX9723 as possible. Route PGND and all
traces that carry switching transients away from SGND
and the audio signal path. Route digital signal traces
away from the audio signal path. Make traces perpen-
dicular to each other when routing digital signals over or
under audio signals.
The thin QFN package features an exposed paddle that
improves thermal efficiency. Ensure that the exposed
paddle is electrically isolated from PGND, SGND, and
VDD. Connect the exposed paddle to SVSS when the
board layout dictates that the exposed paddle cannot
be left floating.
www.maximintegrated.com
Maxim Integrated │ 19
Share Link: 