Pin Number Function
FX806A
J/LG/LS
1
Xtal:
The output of the on-chip clock oscillator. External components are required at this output when
a Xtal circuit is employed. See Figure 2, INSET 2.
2
Xtal/clock:
The input to the on-chip clock oscillator inverter. A Xtal or externally derived clock should
be connected here. See Figure 2, INSET 2. This clock provides timing for on-chip elements, filters etc.
3
Serial Clock:
The “C-BUS,” serial data loading clock input. This clock, produced by the
µController,
is
used for transfer timing of Command Data to the Audio Processor. See Timing diagrams and System
Support Document.
4
Command Data:
The “C-BUS,” serial data input from the
µController.
Command Data is loaded to
this device in 8-bit bytes, MSB (B7) first, and LSB (B0) last, synchronized to the Serial Clock. The
Command/Data instruction is acted upon at the end of loading the whole instruction. Command
information is detailed in Tables 1, 2, 3, 4 and 5. See Timing diagrams and System Support
Document.
5
Chip Select (CS):
The “C-BUS,” data loading control function. This input is provided by the
µController.
Command Data transfer sequences are initiated, completed or aborted by the CS signal.
See Timing diagrams and System Support Document.
6
VOGAD Out:
The output of the relevant VOGAD sensor. This output, with external attack and decay
setting components, should be connected as in Figures 2 and 3, to the VOGAD In pin.
7
Rx Audio In:
The audio input to the FX806A from the radio receiver's demodulator circuits. This
input, which requires to be a.c. coupled with capacitor C
12
, is selected by a Control Command bit.
8
VOGAD In:
The gain control signal from the selected VOGAD sensor (VOGAD Out) to the “Input
Process” Voltage Controlled Amplifier. VOGAD operation is enabled via a Mode Command (Bit5).
Individual sensors, automatically selected, permit gain control from either the Input Process or an
external process. External attack and decay setting components should be applied as recommended
in Figures 2 and 3.
9
V
BIAS
:
The output of the on-chip analogue circuitry bias system, held internally at V
DD
/2. This pin
should be decoupled to V
SS
by a capacitor C
10
, See Figure 2.
10
Mic In (+):
The non-inverting input to the microphone Op-Amp. This input requires external
components for Op-Amp gain/attenuation setting as shown in Figure 2, INSET 1.
11
Mic In (–):
The inverting input to the microphone Op-Amp. This input requires external components
for Op-Amp gain/attenuation setting as shown in Figure 2, INSET 1.
12
V
SS
:
Negative supply rail (GND).
2
CMLMICRO [ CML MICROCIRCUITS ]
