MAX9756ETX+ Maxim Integrated Products, MAX9756ETX+ Datasheet - Page 17
![IC AMP AUDIO PWR 2.3W AB 36TQFN](/photos/6/65/66503/36-tqfn_21-0141i_sml.jpg)
MAX9756ETX+
Manufacturer Part Number
MAX9756ETX+
Description
IC AMP AUDIO PWR 2.3W AB 36TQFN
Manufacturer
Maxim Integrated Products
Series
DirectDrive™r
Type
Class ABr
Datasheet
1.MAX9756ETX.pdf
(31 pages)
Specifications of MAX9756ETX+
Output Type
2-Channel (Stereo) with Stereo Headphones
Max Output Power X Channels @ Load
2.3W x 2 @ 3 Ohm; 130mW x 2 @ 16 Ohm
Voltage - Supply
4.5 V ~ 5.5 V
Features
Depop, Short-Circuit and Thermal Protection, Shutdown, Volume Control
Mounting Type
Surface Mount
Package / Case
36-TQFN Exposed Pad
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
The MAX9756/MAX9757/MAX9758 feature an analog
volume control that varies the gain of the device in 31
discrete steps based upon the DC voltage applied to
VOL (see
(full volume) to HPV
sizes shown in Table 3. Connect the reference of the
device driving VOL (Figure 7) to HPV
to GND (full volume) if volume control is not used.
Table 4. Volume Levels
*Based on HPV
X = Don’t care.
M U L TIPLIE R
Headphone Amplifiers with Automatic Level Control
V
VOL
0.07
0.16
0.18
0.21
0.23
0.25
0.28
0.30
0.32
0.35
0.37
0.39
0.42
0.44
0.46
0.49
0.51
0.54
0.56
0.58
0.61
0.63
0.65
0.68
0.70
0.72
0.75
0.77
0.79
0.82
0.84
0.93
(V) = MULTIPLIER x
HPV
2.3W Stereo Speaker Amplifiers and DirectDrive
Table 4). The input range of VOL is from 0
(MIN)
V
0.00
0.49
0.57
0.64
0.72
0.80
0.88
0.95
1.03
1.11
1.19
1.26
1.34
1.42
1.50
1.57
1.65
1.73
1.80
1.88
1.96
2.04
2.11
2.19
2.27
2.35
2.42
2.50
2.58
2.66
2.73
2.81
DD
VOL
DD
*
= 3.3V.
Analog Volume Control (VOL)
______________________________________________________________________________________
(MAX)
V
0.49
0.57
0.64
0.72
0.80
0.88
0.95
1.03
1.11
1.19
1.26
1.34
1.42
1.50
1.57
1.65
1.73
1.80
1.88
1.96
2.04
2.11
2.19
2.27
2.35
2.42
2.50
2.58
2.66
2.73
2.81
3.30
VOL
DD
*
(full mute), with example step
GA I N 3 = 0
GA I N 2 = 0
GA I N 1 = 0
MUTE
-10
-12
-14
-16
-18
-20
-22
-24
-26
-28
-32
-36
-40
-44
-48
-52
-56
15
14
13
12
10
-2
-4
-6
-8
8
6
4
2
0
GA I N 3 = 0
GA I N 2 = 0
GA I N 1 = 1
MUTE
16.5
-10
-12
-14
-16
-18
-20
-22
-24
-26
-28
-32
-36
-40
-44
-48
16
15
14
13
12
10
-2
-4
-6
-8
8
6
4
2
0
DD
. Connect VOL
GA I N 3 = 0
GA I N 2 = 1
GA I N 1 = 0
MUTE
17.5
16.5
-10
-12
-14
-16
-18
-20
-22
-24
-26
-28
-32
-36
18
17
16
15
14
13
12
10
-2
-4
-6
-8
8
6
4
2
0
GA I N 3 = 0
GA I N 2 = 1
GA I N 1 = 1
SPEAKER MODE
MUTE
19.5
18.5
17.5
16.5
-10
-12
-14
-16
-18
-20
-22
-24
-26
19
18
17
16
15
14
13
12
10
-2
-4
-6
-8
8
6
4
2
0
GAIN (dB)
Figure 7. Volume Control Circuit
GA I N 3 = 1
GA I N 2 = 0
GA I N 1 = 0
MUTE
-10
-12
-14
-16
-18
-20
-22
-26
-30
-34
-38
-42
-46
-50
21
20
19
18
16
14
12
10
-2
-4
-6
-8
8
6
4
2
0
GA I N 3 = 1
GA I N 2 = 0
GA I N 1 = 1
MUTE
V
22.5
-10
-12
-14
-16
-18
-20
-22
-26
-30
-34
-38
-42
22
21
20
19
18
16
14
12
10
REF
-2
-4
-6
-8
DAC
8
6
4
2
0
GA I N 3 = 1
GA I N 2 = 1
GA I N 1 = 0
MUTE
23.5
22.5
-10
-12
-14
-16
-18
-20
-22
-26
-30
24
23
22
21
20
19
18
16
14
12
10
-2
-4
-6
-8
8
6
4
2
0
HPV
VOL
GA I N 3 = 1
GA I N 2 = 1
GA I N 1 = 1
MUTE
DD
25.5
24.5
23.5
22.5
-10
-12
-14
-15
-18
-20
25
24
23
22
21
20
19
18
16
14
12
10
-2
-4
-6
-8
MAX9756
8
6
4
2
0
GA I N 3 = X
GA I N 1 = X
GA I N 2 = 0
HEADPHONE MODE
MUTE
-11
-13
-15
-17
-19
-21
-23
-25
-27
-29
-31
-33
-35
-37
-39
-41
-43
-47
-51
-55
-59
-63
-67
-71
-1
-2
-3
-5
-7
-9
0
GAIN (dB)
GA I N 3 = X
GA I N 2 = 1
GA I N 1 = X
MUTE
2.5
1.5
-11
-13
-15
-17
-19
-21
-23
-25
-27
-29
-31
-33
-35
-37
-39
-41
-43
-47
-51
-1
-2
-3
-5
-7
-9
3
2
1
0
17