mc34216adwf Freescale Semiconductor, Inc, mc34216adwf Datasheet - Page 10

• Manufacturer Part Number: mc34216adwf
• Description: Programmable Telephone Line Interface Circuit With Loudspeaker Amplifier
• Manufacturer: Freescale Semiconductor, Inc

ILK, which is calculated:
takes place for line currents of 30 mA to 40 mA depending
on the components settings. With the Startup and Low
Voltage mask, the transfer lies outside the normal operating
range with line currents of 90 mA or more. In most
applications, the transfer from Region 1 to 2 takes place for
line currents below 10 mA.
overload condition. In this mode, the power consumption in
the telephone set is limited. In order to detect an overload
condition, the voltage between the Pins LAI and SAO is
monitored. When the voltage difference is larger than the
threshold V clamp1 , the protection is made active. The relation
for the line voltage VLP at this point is given as:
Line +
Line –
10
The transfer from Region 2 to 3 occurs at the point VLK,
When the French or U.K. mask is selected, this transfer
With proper settings, Region 4 is only entered during an
VLK
ILK
With : I2CD
and 2V
+
VLP
+
Z21
BE
Z0
Z1 x I2CD
Z1
+
[
HYN
x Z1 x I2CD
+
Z21
I2
Z0
1.4 V, V
I2C
+
x V
)
)
2
clamp1
G
O2
I2D
CM
2V
R1
C16
BE
)
[
, and V
Figure 4. DC Part of the Block Diagram of the MC34216A
2V
1.1 V
)
)
NDC
BE
C12
V
V
CD
CD
IMP
CD
)
)
)
+
+
2.4 V
SAI
RX
V
V
V
O2
CD
V
O2
C
)
2V
2
+
BE
MC34216A
V
+
D
V O1
1.4 V
,
+
SAO
reduced to a lower value ILP of:
overload condition is gone and the MC34216A will leave
Region 4.
supply the MC34216A and peripheral circuits. The surplus of
current is sunk away by the voltage stabilizer at Pin V CC
where a reservoir capacitor is connected. The reference for
the circuit is Pin Gnd.
circuit. During the startup, the internal registers of the
MC34216A are reset, and the reset Pin R S goes high. This
signals is meant to indicate to the microcontroller that the
programming of the MC34216A can start.
Pin D/HS goes high. This serves as the information for the
microcontroller that the set is off–hook. When the line current
is no longer present, the pin goes low again. Because the line
current is monitored, and not the line voltage, an interrupt of
the exchange can be recognized.
When the protection mode is entered, the line current is
When the line voltage becomes smaller than VLP, the
The current drawn from the line by the dc part is used to
Startup of the application is ensured by an internal startup
When the line current flows, the hook status output
MC34216A
Z21
ILP
Z0
+
LAI
MOTOROLA ANALOG IC DEVICE DATA
V
clamp2
V
O2
+
+
R1
)
R1
LAO
Gnd
V
O1
– V
T2
T3
O2
R5
+
C7
V
CC