mc34216adwf Freescale Semiconductor, Inc, mc34216adwf Datasheet - Page 8

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

Concept
mode power supply, a telephone set with listening–in function
and ringing via loudspeaker can be built as shown in
Figure 1.
line current flows through transistor T2 and supplies the
application at the supply point V CC which is stabilized by the
MC34216A. The V line , I line characteristic is programmed by
the microcontroller and adjusted by the external components
Z0, Z1, Z21 and R1 which are in a regulator loop, acting on
transistor T2. The ac impedance is generated in a similar way.
Handset and loudspeaker can be connected directly to the
8
With the MC34216A, a microcontroller and a switched
In off–hook position, the application is in speech mode. The
A/B
Pin
21
22
23
24
25
26
27
28
Hookswitch
Loudspeaker
Symbol
RXO1
RXO2
V CC
AGC
Gnd
LPO
RXI
LPI
Figure 1. Telephone Concept with MC34216A
PIN FUNCTION DESCRIPTION (continued)
Handset
CIRCUIT DESCRIPTION
MC34216A
Z1
Supply Voltage
Large Signal Ground
Loudspeaker Amplifier Output
Loudspeaker Amplifier Input
Receive Amplifier Input
Receive Amplifier Output
Receive Amplifier Output
Loudspeaker AGC Timing
MC34216A
Z21
R1
MC34216A to perform handset and listening–in operation.
Via the bus, the microcontroller programs the MC34216A to
perform the DTMF/pulse–dialing and supervise the device.
The user keyboard has to be connected to the microcontroller.
presence of a ringing signal. The microcontroller programs
the MC34216A and a ringing melody can be generated via
the loudspeaker.
shows the basic blocks of the device plus the essential
external components.
In on–hook position, the SMPS supplies the application in
The block diagram of the MC34216A (see Figure 2),
Z0
MOTOROLA ANALOG IC DEVICE DATA
Description
T2
V CC
Gnd
Micro
SMPS