Application Information
V
DD
C
5
V
SS
Q3
DATA OUTPUTS
A HEX Code
Output representing
the decoded tone
frequency
See Table 1
1
2
3
4
V
DD
16
15
14
DATA CHANGE
CS
IRQ
P U R S
HOLD
V
SS
XTAL/CLOCK
R
1
C
1
Q2
Q1
Q0
FX623P
13
12
11
10
9
5
6
7
COMPOSITE SIGNAL IN
SIGNAL IN
C
2
XTAL
8
X
1
C
3
V
SS
R
2
C
4
Fig.2 Recommended External Components
Hex
Output Code
Character Q3 Q2 Q1 Q0
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Band Edges (Hz) Nominal
Lower
Upper
Centre
Edge
Edge
Freq.
364
488
520
580
386
412
436
463
900
1273
1350
1750
2062
386
520
580
618
412
436
463
487
1008
1325
1455
1855
2140
Component
R
1
R
2
C
1
C
2
C
3
C
4
C
5
X
1
Value
1.0MΩ
1.0MΩ
47.0nF
4.7nF
33.0pF
33.0pF
1.0µF
3.579545MHz
375
500
550
600
400
425
450
475
950
1300
1400
1800
2100
Tolerances R = ±10%
C = ±20%
frequency not guaranteed
frequency not guaranteed
N
OTONE
Table 1 Tone Decode Frequencies
Timing Information
With CS Low - Figure 3.
After initial power-up and the Hold input inactive
(High), as frequencies are input, with the Data Change
output as an active (High) indicator, the data is
presented at the Data Outputs.
If/when the Hold input is placed active (Low), the
data at the Data Outputs is frozen and the Data
Change output held High at its next active excursion -
until the Hold input is returned High.
3
With the Hold input held High - Figure 4.
As frequencies are input a correct decode will
produce an active (Low) interrupt level.
This interrupt (IRQ) is serviced and reset by an
active (Low) CS input.
Note the ‘valid data’ period at the Data Outputs.
CMLMICRO [ CML MICROCIRCUITS ]
