Chapter 2: ADC-6880 Analog to AES/EBU Digital Audio Converter
Configuration
24
6800/7000 Series - Audio and Video Multi/Demultiplexing Products Installation and Operation Manual
Reset Button
The
SW1
momentary push button located at the front edge of the
ADC-6880 initiates a reset and an internal calibration of the A-to-D
converter input circuitry (
see
“LED Indicators”, on page 25)
.
The
internal calibration is also performed each time power is applied to the
ADC-6880. The
SW1
button is a momentary push button that, when
pressed and released, initiates the
Reset
mode of the A-to-D converter
IC. It also mutes the digital data at the output of the ADC-6880. During
this reset time (approximately 1 second), the analog audio input signal is
disconnected, and the inputs are shorted to ground. This is
accomplished via relays RL1 and RL2.
Inputs are not shorted to ground.
The reset procedure removes any DC offsets present on the ADC-6880
input circuit and any DC offset in the A-to-D converter IC’s internal
input stage.
Figure 2-5.
Location of Reset (Calibration) Button
SW3
SW2
INT
AUTO
EXT
48
KHz
44.1
KHz
PWR
48KHz
44.1KHz
REF ERR
EXT REF
SW1
CAL
1
J1
16dB
u
J1
2
1
6dB
u
J2
18dB
u
J1
3
1
8dB
u
J3
20dB
u
J1
4
2
0dB
u
J1
5 2
2dB
u
J5
24dB
u
J1
6 2
4dB
u
J6
26dB
u
J1
7
2
6dB
u
J7
28dB
u
J1
8
2
8dB
u
J8
30dB
u
J1
9
3
0dB
u
J10 J9
AC
DC
J21
J20
J21
ADC-6880
SER.
NO.
SER.
NO.
J4
22dB
u
R15
R21
R113
R125
R15
AC
DC
AC
DC
AC
DC
SW1
CAL