Owner manual

MAX9712
500mW, Low EMI, Filterless,
Class D Audio Amplifier
_______________________________________________________________________________________ 5
0
30
20
10
50
40
90
80
70
60
100
2.5 3.0 3.5 4.0 4.5 5.0 5.5
EFFICIENCY vs. SUPPLY VOLTAGE
MAX9712TOC13
SUPPLY VOLTAGE (V)
EFFICIENCY (%)
R
L
= 8Ω
f = 1kHz
R
L
= 6Ω R
L
= 16Ω
0
30
20
10
50
40
90
80
70
60
100
800 1000 1200 1400 18001600 2000
EFFICIENCY
vs. SYNC INPUT FREQUENCY
MAX9712TOC14
SYNC FREQUENCY (kHz)
EFFICIENCY (%)
R
L
= 8Ω
V
DD
= 3.3V
f = 1kHz
P
OUT
= 300mW
0
500
400
200
100
300
700
600
900
800
1000
2.5 3.1 3.7 4.3 4.9 5.5
OUTPUT POWER
vs. SUPPLY VOLTAGE
MAX9712TOC15
SUPPLY VOLTAGE (V)
OUTPUT POWER (mW)
f = 1kHz
R
L
= 6Ω
R
L
= 8Ω
R
L
= 16Ω
0
300
200
100
500
400
900
800
700
600
1000
01020 4030 80706050 10090
OUTPUT POWER
vs. LOAD RESISTANCE
MAX9712TOC16
LOAD RESISTANCE (Ω)
OUTPUT POWER (mW)
V
DD
= 5V
V
DD
= 3.3V
f = 1kHz
THD+N = 1%
0
-100
10 100 1k 10k 100k
COMMON-MODE REJECTION RATIO
vs. FREQUENCY
-80
MAX1972TOC17
FREQUENCY (Hz)
CMRR (dB)
-60
-40
-20
-30
-50
-70
-90
-10
INPUT REFERRED
V
IN
= 200mV
P-P
0
-100
10 100 1k 10k 100k
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
-80
MAX1972TOC18
FREQUENCY (Hz)
PSRR (dB)
-60
-40
-20
-30
-50
-70
-90
-10
OUTPUT REFERRED
INPUTS AC GROUNDED
V
DD
= 3.3V
GSM POWER-SUPPLY REJECTION
MAX9712TOC19
MAX9712
OUTPUT
V
DD
100µV/div
500mV/div
2ms/div
f = 217Hz
INPUT LOW = 3V
INPUT HIGH = 3.5V
DUTY CYCLE = 88%
R
L
= 8Ω
-140
-100
-120
-60
-80
-20
-40
0
OUTPUT FREQUENCY SPECTRUM
MAX9712TOC20
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dBV)
0 5k 10k 15k 20k
FFM MODE
V
OUT
= -60dBV
f = 1kHz
R
L
= 8Ω
UNWEIGHTED
Typical Operating Characteristics (continued)
(V
DD
= 3.3V, V
SYNC
= GND, T
A
= +25°C, unless otherwise noted.)