Owner's manual
MAX9791/MAX9792
Windows Vista-Compliant Class D Speaker
Amplifiers with DirectDrive Headphone Amplifiers
_______________________________________________________________________________________ 5
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
COM Input Range V
COM
Inferred from CMRR test -300 +300 mV
Common-Mode Rejection Ratio CMRR -300mV < V
COM
< +300mV 60 dB
Slew Rate SR 0.38 V/µs
Charge-Pump Frequency f
OSC
530 kHz
BEEP INPUT (LDO_EN = 1)
Beep Signal Minimum Frequency f
BEEP
Four-cycle count 215 Hz
Amplifier Turn-On Time t
ONBEEP
400 µs
Amplifier Hold Time t
HOLDBEEP
221 246 271 ms
LOW-DROPOUT LINEAR REGULATOR
Regulator Input Voltage Range V
AVDD
Inferred from line regulation,
V
LDO_OUT
= 4.75V
4.5 5.5 V
LDO Ground Current I
LDO
0.25 0.4 mA
Output Current I
OUT
Inferred from load regulation 120 mA
Current Limit I
LIM
300 mA
Crosstalk
Speaker to LDO, V
LDO_OUT
= 4.75V,
f =1kHz, I
LDO_OUT
= 10mA, speaker P
OUT
= 1.2W, R
L
= 8Ω
-80 dB
V
LDO_OUT
= 4.75V ±1.5
Output-Voltage Accuracy
V
LDO_OUT
= 3.3V ±1.5
%
I
OUT
= 50mA 46
Dropout Voltage V
DO
V
LDO_OUT
= 4.75V,
T
A
= +25°C (Note 7)
I
OUT
= 120mA 106
mV
Startup Time 30 µs
V
LDO_OUT
= 4.75V -4.8 1.5 +4.8
Line Regulation
V
AVDD
= 4.5V to
5.5V,
I
LDO_OUT
= 1mA
V
LDO_OUT
= 3.3V -4 0.2 +4
mV/V
Load Regulation
V
LDO_OUT
= 4.75V, 1mA < I
LDO_OUT
<
120mA
0.22 mV/mA
f = 1kHz 56
Ripple Rejection
V
RIPPLE
= 200mV
P-P
,
V
LDO_OUT
= 4.75V
I
LDO_OUT
= 10mA
f = 10kHz 40
dB
Output-Voltage Noise
20Hz to 20kHz, C
LDO_OUT
= 2 x 1µF,
I
LDO_OUT
= 120mA
130 µV
RMS
DIGITAL INPUTS (SPKR_EN, HP_EN, LDO_EN, BEEP)
Input-Voltage High V
INH
2V
Input-Voltage Low V
INL
0.4 V
Input Bias Current -1 +1 µA
ELECTRICAL CHARACTERISTICS (continued)
(V
AVDD
= V
PVDD
= V
HPVDD
= 5V, V
GND
= V
PGND
= V
CPGND
= 0, I
LDO_OUT
= 0, C
LDO
= 2µF, C1 = C2 = 1µF. R
L
= ∞, unless other-
wise specified. R
IN1
= 20kΩ (A
VSPKR
= 12dB), R
IN2
= 40.2kΩ (A
VHP
= 0dB), C
IN1
= 470nF, C
IN2
= C
COM
= 1µF, T
A
= T
MIN
to T
MAX
,
unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 3)










