MAX9752BETI+ Maxim Integrated Products, MAX9752BETI+ Datasheet - Page 20

• Manufacturer Part Number: MAX9752BETI+
• Description: IC AMP AUDIO PWR 2.2W D 28TQFN
• Manufacturer: Maxim Integrated Products
• Series: DirectDrive™r
• Type: Class Dr

Specifications of MAX9752BETI+

• Output Type: 2-Channel (Stereo) with Stereo Headphones
• Max Output Power X Channels @ Load: 2.2W x 2 @ 4 Ohm; 62mW 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: 28-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2.2W, Low-EMI, Stereo, Class D Power Amplifiers
with DirectDrive Headphone Amplifiers
Figure 9. MAX9752 Volume-Control Circuit
Figure 10a. MAX9752A Volume-Control Transfer Functions
Figure 10b. MAX9752B Volume-Control Transfer Functions
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V
-10
-20
-30
-40
-50
-60
-70
-80
-10
-20
-30
-40
-50
-60
-70
-80
REF
20
10
20
10
DAC
0
0
VOLUME-CONTROL TRANSFER FUNCTION
VOLUME-CONTROL TRANSFER FUNCTION
0
0
0.5
0.5
HEADPHONE MODE
HEADPHONE MODE
1.0
1.0
1.5
1.5
MAX9752A
MAX9752B
V
V
HPV
VOL
VOL
VOL
2.0
2.0
SPEAKER MODE
(V)
(V)
DD
SPEAKER MODE
MAX9752
GAIN1 = GAIN2 = 0
GAIN1 = GAIN2 = 0
2.5
2.5
3.0
3.0
TAPER POT
TAPER POT
AUDIO
AUDIO
3.5
3.5
4.0
4.0
The MAX9752 features an audible alert beep input
(BEEP). BEEP serves as the alert signal detector and the
alert input to the amplifiers. AC-couple the alert output of
a µC to BEEP. The MAX9752 monitors the signal at
BEEP. When a signal exceeding 400mV
quency greater than 300Hz is detected at BEEP, the
MAX9752 connects the signal to the amplifiers after eight
periods of the input signal. In speaker mode, the alert
signal appears at both speaker outputs, mixed with any
audio that may be present. In headphone mode, the alert
signal appears at the headphone outputs, mixed with
any audio that may be present. A signal with less than
eight input periods is ignored. Multiple BEEP signals can
be summed as shown in Figure 11. Adding external
resistors in series with BEEP increase the minimum volt-
age amplitude sensitivity.
The MAX9753 features a 2:1 input multiplexer on each
amplifier, allowing input selection between two stereo
sources. The logic input IN1/2 controls both multiplexers.
A logic-high selects input IN_1 and a logic-low selects
input IN_2. The unselected inputs are high impedance.
The MAX9752/MAX9753/MAX9754 feature an 8µA, low-
power shutdown mode reducing quiescent current con-
sumption and extending battery life. Driving SHDN low
disables the drive amplifiers, bias circuitry, charge
pump, and sets the headphone amplifier output imped-
ance to 1kΩ, and drives BIAS to GND. Connect SHDN to
V
Figure 10c. MAX9752C Volume-Control Transfer Functions
DD
for normal operation.
-10
-20
-30
-40
-50
-60
-70
-80
20
10
0
VOLUME-CONTROL TRANSFER FUNCTION
0
HEADPHONE MODE
0.5
1.0
1.5
MAX9752C
Beep Input (MAX9752)
Input Mux (MAX9753)
V
VOL
2.0
(V)
SPEAKER MODE
2.5
GAIN1 = GAIN2 = 0
3.0
TAPER POT
AUDIO
3.5
P-P
Shutdown
4.0
with a fre-