TEA1062AN-D16-T UTC [Unisonic Technologies], TEA1062AN-D16-T Datasheet - Page 7

• Manufacturer Part Number: TEA1062AN-D16-T
• Description: LOW VOLTAGE TELEPHONE TRANSMISSION CIRCUIT WITH DIALLER INTERFACE
• Manufacturer: UTC [Unisonic Technologies]

TEA1062N/TEA1062AN
Supply: V
The IC supply voltage is derived from the line via a dropping resistor and regulated by the UTC
TEA1062N/TEA1062AN. The supply voltage Vcc may also be used to supply external circuits e.g. dialling and
control circuits. Decoupling of the supply voltage is performed by a capacitor between Vcc and V
voltage regulator is decoupled by a capacitor between REG and V
accordance with varying values of the exchange voltage (Vexch), the feeding bridge resistance (Rexch) and the DC
resistance of the telephone line (R
at a level determined by a 3.6kΩ resistor connected between STAB and V
is more than 0.5mA greater than the sum of the IC supply current (Icc) and the current drawn by the peripheral
circuitry connected to V
terminal(V
where: Vref is an internally generated temperature compensated reference voltage of 3.7V and R9 is an external
resistor connected between SLPE and V
will also affect microphone gain, DTMF gain, gain control characteristics, side tone level, maximum output swing on
LN and the DC characteristics (especially at the lower voltages). Under normal conditions, when I
I
the audio frequency range the dynamic impedance is largely determined by R1. Fig.3 shows the equivalent
impedance of the circuit.
at 1mA) This means that more sets can be operated in parallel with DC line voltages (excluding the polarity guard)
down to an absolute minimum voltage of 1.6V. With line currents below 9mA the circuit has limited sending and
receiving levels. The internal reference voltage can be adjusted by means of an external resistor(R
when connected between LN and REG will decrease the internal reference voltage and when connected between
REG and SLPE will increase the internal reference voltage. Current(I
depends on the external components used. Fig.9 shows this current for V
(TEA1062AN is HIGH) when the receiving amplifier is driven the available current is further reduced. Current
availability can be increased by connecting the supply IC(1081) in parallel with R1, as shown in Fig.16, or, by
increasing the DC line voltage by means of an external resistor(R
MICROPHONE INPUTS(MIC+ AND MIC-) AND GAIN PINS (GAS1 AND GAS2)
gain is typically 52 dB (when R7=68kΩ. see Fig.13). Dynamic, magnetic, piezoelectric or electret (with built-in FET
source followers) can be used. Microphone arrangements are illustrated in Fig.10. The gain of the microphone
amplifier can be adjusted between 44dB and 52dB to suit the sensitivity of the transducer in use. The gain is
proportional to the value of R7 which is connected between GAS1 and GAS2. Stability is ensured by the external
capacitors, C6 connected between GAS1 and SLPE and C8 connected between GAS1 and V
100pF but this may be increased to obtain a first-order low-pass filter. The value of C8 is 10 times the value of C6.
The cut-off frequency corresponds to the time constant R7*C6.
MUTE INPUT (MUTE/MUTE)
microphone inputs and the receiving amplifier inputs; a HIGH (UTC TEA1062N is LOW) level or an open circuit does
the reverse. Switching the mute input will cause negligible clicks at the telephone outputs and on the line. In case the
line current drops below 6mA (parallal opration of more sets) the circuit is always in speech condition independant of
the DC level applied to the MUTE/MUTE input.
DUAL-TONE MULTI-FREQUENCY INPUT (DTMF)
typically 25.5dB(when R7=68kΩ) and varies with R7 in the same way as the microphone gain. The signalling tones
can be heard in the earpiece at a low level (confidence tone).
P
, the static behavior of the circuit is that of a 3.7V regulator diode with an internal resistance equal to that of R9. In
Power for the UTC TEA1062N/TEA1062AN and its peripheral circuits is usually obtained from the telephone line.
The UTC TEA1062N/TEA1062AN has symmetrical inputs. Its input impedance is 64kΩ (2*32kΩ) and its voltage
A LOW (UTC TEA1062N is HIGH) level at UTC TEA1062AN MUTE enables DTMF input and inhibited the
When the DTMF input is enabled dialling tones may be sent onto the line. The voltage gain from DTMF to LN is
At line currents below 9mA the internal reference voltage is automatically adjusted to a lower value(typically 1.6V
FUNCTIONAL DESCRIPTION
V
V
LN
CC
LN
LN
) can be calculated as:
=Vref+I
=Vref+[( I
UNISONIC TECHNOLOGIES CO., LTD
, LN, SLPE, REG and STAB
www.unisonic.com.tw
SLPE
LINE
*R9 or;
CC
– I
(lp) the excess current is shunted to V
CC
- 0.5*10 - 3 A)－I
LINE
). The UTC TEA1062N/TEA1062AN has an internal current stabilizer operating
EE
. In normal use the value of R9 would be 20Ω. Changing the value of R9
P
]*R9
EE
VA
. The DC current drawn by the device will vary in
P
) connected between REG and SLPE.
EE
) available from V
LINEAR INTEGRATED CIRCUIT
via LN. The regulated voltage on the line
CC
EE
> 2.2V. If MUTE of TEA1062N is LOW
(see Fig.8). When the line current(I
CC
for peripheral circuits
EE
. The value of C6 is
EE
SLPE
VA
while the internal
). This resistor
≧I
CC
QW-R108-011.C
+0.5mA +
7 of 13
LINE
)