FX828 Datasheet, PDF (5/34 Pages) CML Microcircuits – CTCSS/DCS/SELCALL Processor

CTCSS/DCS/SELCALL Processor
FX828
1.3 Signal List (continued)
Package
D2/D5/P4
Signal
Pin No.
Name
8
COMPOUT
9
COMPIN
10
A/D CAP 1
11
A/D CAP 2
12
Vss
13
V_BIAS
14
RX AMP IN
15
RX AMP OUT
16
RX AUDIO OUT
17
TX AUDIO OUT
18
SUM IN
19
SUM OUT
20
MOD1 IN
21
TX SUB AUDIO OUT
22
MOD1
23
MOD2
24
V_DD
Description
Type
O/P The output of the comparator.
I/P The input to the comparator.
O/P An internal reference voltage for the CTCSS A
to D. Decouple to V_SS with an external
capacitor.
O/P
Power
An internal reference voltage for the DCS A to
D. Decouple to V_SS with an external capacitor.
The negative supply rail (ground).
O/P A bias line for the internal circuitry, held at ½
V_DD. This pin must be decoupled by a capacitor
mounted close to the device pins.
I/P The inverting input to the Rx input amplifier.
O/P The output of the Rx input amplifier and the
input to the audio filter section.
O/P Output of the Rx audio filter section.
O/P Output of the selcall tone generator.
I/P Input to the audio summing amplifier.
O/P Output of the audio summing amplifier.
I/P Input to MOD1 audio gain control.
O/P Output of the CTCSS or DCS Tx tone generator.
O/P Output of MOD1 audio gain control.
O/P Output of MOD2 audio gain control.
Power
The positive supply rail. Levels and voltages are
dependent upon this supply. This pin should be
decoupled to V_SS by a capacitor.
Notes: I/P = Input
O/P = Output
© 2009 CML Microsystems Plc
5
D/828/4