MAX9723
Stereo DirectDrive Headphone Amplifier
with BassMax, Volume Control, and I2C
8
_______________________________________________________________________________________
Typical Operating Characteristics (continued)
(VDD = SHDN = 3V, PGND = SGND = 0V, C1 = C2 = 1F, BB_ = 0V, gain = 0dB, maximum volume, BassMax disabled. Load con-
nected between OUT_ and SGND where specified. Outputs in phase, both channels loaded. TA = +25°C, unless otherwise noted.)
(See Functional Diagram/Typical Operating Circuit)
OUTPUT POWER vs. CHARGE-PUMP
CAPACITANCE AND LOAD RESISTANCE
MAX9723
toc22
LOAD RESISTANCE (
Ω)
OUTPUT
POWER
(mW)
40
30
20
40
45
50
55
60
65
70
75
35
10
50
C1 = C2 = 2.2
μF
C1 = C2 = 0.68
μF
C1 = C2 = 1
μF
VDD = 3V
fIN = 1kHz
THD+N = 1%
POWER-UP/POWER-DOWN
WAVEFORM
MAX9723 toc23
20ms/div
VDD
2V/div
VOUT
10mV/div
EXITING SHUTDOWN
MAX9723 toc24
40
μs/div
VOUT_
200mV/div
VSHDN
2V/div
ENTERING SHUTDOWN
MAX9723 toc25
20
μs/div
VOUT_
200mV/div
VSHDN
2V/div
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX9723
toc26
SUPPLY VOLTAGE (V)
SUPPLY
CURRENT
(mA)
3.4
3.2
3.0
2.8
2.6
2.4
2.2
2.0
2.5
3.0
3.5
4.0
4.5
2.0
1.8
3.6
NO LOAD
INPUTS GROUNDED
SHUTDOWN CURRENT
vs. SUPPLY VOLTAGE
SHUTDOWN
CURRENT
(μ
A)
1
2
3
4
5
6
7
8
0
MAX9723
toc27
SUPPLY VOLTAGE (V)
3.4
3.2
3.0
2.8
2.6
2.4
2.2
2.0
1.8
3.6
NO LOAD
INPUTS GROUNDED