TK10651MTL TOKO, TK10651MTL Datasheet - Page 9

• Manufacturer Part Number: TK10651MTL
• Description: LOW VOLTAGE COMPANDOR
• Manufacturer: TOKO

COMPRESSOR
By placing the data input pin following the compressor
circuit, a data signal can be transmitted without being
compressed. Audio from the microphone can be connected
directly to the IC, because it passes through the built-in
microphone amplifier (the gain is adjustable). Since there is
a built-in limiter to prevent overmodulation, it is not neces-
sary to add an external Instantaneous Deviation Control
(IDC) circuit; furthermore, a Low Pass Filter (LPF) up to the
third order can be constructed using the buffer amplifier.
When a data signal is being transmitted, the unneeded
audio can be cut by engaging the mute switch.
EXPANDER
A wide range of applications are made possible because all
of the input amplifier pins are accessible. A LPF of up to the
third order can be constructed at the input, and with an
external resistor, it can be used as an amplifier. If the data
out pin is used for the output, a data signal can be extracted
without passing through the expander. During data trans-
mission, the audio signal system can be inhibited by using
the mute switch.
January 2000 TOKO, Inc.
APPLICATION INFORMATION
COMPRESSOR MICROPHONE AMPLIFIER
The input pin connects to the reference voltage through a
100 k bias resistor, therefore external bias is not neces-
sary. The microphone amplifier gain can be adjusted by
connecting an external resistor to NF pin 7. The gain is
highest when no resistor is added, and the standard input
level is 3 mV. When an external resistor of 9.1 k is added,
the standard input level is about a 10 mV; when the external
resistor value is 68 k , the standard input level is 30 mV.
The input can accommodate a variety of microphones by
adjusting the gain to match the microphone's output volt-
age.
The user should set the gain and input level so that the
output level at pin 3 is normally 300 mV (standard level).
~10 mV
~3 mV
9.1 k
COMP NF
COMP IN
COMP NF
COMP IN
8
7
7
7
8
3.3 k
3.3 k
100 k
100 k
+
-
+
-
51 k
51 k
TK10651
V
V
REF
REF
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