MAX9726
DirectDrive, Headphone Amplifier with
BassMax, I
2
C, Volume and Gain Control
4
_______________________________________________________________________________________
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
f = 1kHz, 100mV
P-P
ripple 85
Power-Supply Rejection Ratio
(Note 2)
PSRR
f = 20kHz, 100mV
P-P
ripple 73
dB
BW = 22Hz to 22kHz 101
Signal-to-Noise Ratio SNR
R
L
= 32Ω,
V
OUT
= 1.5V
RMS A-weighted 104
dB
Into shutdown 62
Click-and-Pop Level K
CP
Peak voltage,
A-weighted, 32
samples per
second
(Notes 2, 4)
Out of shutdown 67
dBV
ELECTRICAL CHARACTERISTICS (3.3V Supply) (continued)
(V
DD
= SHDN = 3.3V, PGND = SGND = 0V, C1 = C2 = 1µF, C
PREG
= C
NREG
= 1µF, BM_ = 0V, R
IN
= 10kΩ, R
F
= 10kΩ, maximum
volume (overall gain = 0dB), BassMax disabled. Load connected between OUT_ and PGND where specified. T
A
= T
MIN
to T
MAX
,
unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Serial Clock Frequency f
SCL
0 400 kHz
Bus Free Time Between a STOP and a
START Condition
t
BUF
1.3 µs
Hold Time Repeated for a START
Condition
t
HD:STA
0.6 µs
Low Period of the SCL Clock t
LOW
1.3 µs
High Period of the SCL Clock t
HIGH
0.6 µs
Setup Time for a Repeated START
Condition
t
SU:STA
0.6 µs
Data Hold Time t
HD:DAT
0 0.9 µs
Data Setup Time t
SU:DAT
100 ns
Rise Time of Both SDA and SCL Signals t
r
300 ns
Fall Time of Both SDA and SCL Signals t
f
300 ns
Setup Time for STOP Condition t
SU:STO
0.6 µs
Pulse Width of Suppressed Spike t
SP
50 ns
Capacitive Load for Each Bus Line C
L_BUS
400 pF
TIMING CHARACTERISTICS
(V
DD
= SHDN = 5V, PGND = SGND = 0V, C1 = C2 = 1µF, C
PREG
= C
NREG
= 1µF, BM_ = 0V, R
IN
= 10kΩ, R
F
= 10kΩ, maximum vol-
ume (overall gain = 0dB), BassMax disabled. Load connected between OUT_ and PGND where specified. T
A
= T
MIN
to T
MAX
, unless
otherwise noted. Typical values are at T
A
= +25°C.) (Notes 1, 3)
Note 1: All specifications are 100% tested at T
A
= +25°C. Temperature limits are guaranteed by design.
Note 2: Inputs AC-coupled to SGND.
Note 3: Guaranteed by design.
Note 4: Headphone testing performed with a 32Ω resistive load connected to PGND. Mode transitions are controlled by SHDN. K
CP
level is calculated as 20log[(peak voltage during mode transition, no input signal)/1V
RMS
]. Units are expressed in dBV.
