Rainbow Electronics MAX9890 - Manual (Page 7)

Switches
The MAX9890’s internal switches connect the input to the
output after the coupling capacitors are fully charged.
The MAX9890A holds the switches open for 200ms and is
ideal for coupling capacitors less than 100µF. The
MAX9890B has a longer turn-on time of 330ms and is
ideal with larger coupling capacitors less than 220µF. The
internal switches have a low on-resistance (R
ON = 0.5
Ω)
and on-resistance flatness (R
FLAT(ON)
= 2m Ω) minimizing
total harmonic distortion plus noise (THD+N). The rela-
tionship below shows the contribution to THD+N through
the switch, due to on-resistance and on-resistance flat-
MAX9890
Audio Click-Pop Suppressor
_______________________________________________________________________________________ 7
40ms/div
FFT: 25Hz/div
V OUT
1V/div
V CC /SHDN
2V/div
V HEADPHONE
100mV/div
FFT HEADPHONE
20dB/div
0dB
Figure 1. Startup/Power-Up Sequence Without Click-Pop
Suppression
40ms/div
FFT: 25Hz/div
V OUT
1V/div
V HEADPHONE
50mV/div
FFT HEADPHONE
20dB/div
V
CC
/SHDN
2V/div
0dB
Figure 2. Startup/Power-Up Sequence With Click-Pop
Suppression
100ms/div
FFT: 25Hz/div
V
OUT
1V/div
V HEADPHONE
500mV/div
V
CC
/SHDN
2V/div
FFT HEADPHONE
20dB/div
0dB
Figure 3. Shutdown/Power-Down Sequence Without Click-Pop
Suppression
100ms/div
FFT: 25Hz/div
V OUT
1V/div
V
HEADPHONE
20mV/div
FFT HEADPHONE
20dB/div
V CC /SHDN
2V/div
0dB
Figure 4. Shutdown/Power-Down Sequence With Click-Pop
Suppression