ne567f NXP Semiconductors, ne567f Datasheet - Page 9

• Manufacturer Part Number: ne567f
• Description: Tone Decoder/phase-locked Loop
• Manufacturer: NXP Semiconductors

Philips Semiconductors Linear Products
In cases where turn-off time can be sacrificed to achieve fast
turn-on, the optional sensitivity adjustment circuit can be used to
move the quiescent C
voltage). However, sensitivity to beat frequencies, noise and
extraneous signals will be increased.
OPTIONAL CONTROLS
The 567 has been designed so that, for most applications, no
external adjustments are required. Certain applications, however,
will be greatly facilitated if full advantage is taken of the added
control possibilities available through the use of additional external
components. In the diagrams given, typical
values are suggested where applicable. For best results the
resistors used, except where noted, should have the same
temperature coefficient. Ideally, silicon diodes would be
low-resistivity types, such as forward-biased transistor base-emitter
junctions. However, ordinary low-voltage diodes should be adequate
for most applications.
April 15, 1992
Tone decoder/phase-locked loop
C
C
2
3
+
+
130
260
f
f
O
O
NOTE:
130
f
Adjust control for symmetry of detection band edges
about f
250
200
150
100
O
50
PIN 2
567
0
m F
m F
0
10k )
0.5k 0.9k 1.4k 1.9k
O
.
R
Figure 6. BW Reduction
2
3
voltage lower (closer to the threshold
DETECTION BAND — % OF f
R
50k
R
4
C
A
2
t
C 2 t
6
V+
(Figure 3)
8
R
R
OPTIONAL SILICON
DIODES FOR
TEMPERATURE
COMPENSATION
1300
2.5k 3.2k 4.0k
f
B
C
R + R
O
10
10k )
A
12
R
100k
)
10k
O
20k
R
R
14
R B )
R B R
16
C
R
C
411
SENSITIVITY ADJUSTMENT
When operated as a very narrow-band detector (less than 8
percent), both C
noise and out-band signal rejection. This will inevitably slow the
response time. If, however, the output stage is biased closer to the
threshold level, the turn-on time can be
improved. This is accomplished by drawing additional current to
terminal 1. Under this condition, the 567 will also give an output for
lower-level signals (10mV or lower).
By adding current to terminal 1, the output stage is biased further
away from the threshold voltage. This is most useful when, to obtain
maximum operating speed, C
Normally, frequencies just outside the detection band could cause
false outputs under this condition. By desensitizing the output stage,
the out-band beat notes do not feed through to the output stage.
Since the input level must
NOTE:
C
A
prevents latch-up when power supply is turned on.
UNLATCH
2
UNLATCH
and C
Figure 7. Output Latching
10k
R
3
A
V+
are made quite large in order to improve
V+
C
2
A
and C
567 8
1
567 8
1
C
3
C
3
(Figure 3)
are made very small.
3
R
20k
f
R
20k
f
V+
V+
R
R
L
NE/SE567
L
Product specification