mc34216adwf Freescale Semiconductor, Inc, mc34216adwf Datasheet - Page 18

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

integrated filters. The DTMF pairs can be selected by the
microcontroller via the MF bits. In this way, the whole DTMF
range for a 4x4 keyboard is available which fulfills the CCITT
requirements. The DTMF level on the line can be adjusted
by external components and it can also be programmed via
the MF bits.
switched on and the anti–howling circuitry has to be
activated. The loudspeaker is switched on by making the
G2G1G0 bits high. They also set the volume. The
anti–howling circuit is activated by making bit HPI low. By
making bit M th high, the microphone threshold feature is
enabled which further reduces the effect of howling.
programmed. This automatically disables the earpiece by
muting the RXO2 output, and it enables the AHO1 input as a
speakerphone signal input. By making the MicP bit low, the
handset microphone is no longer powered and is thus muted.
This ensures that only the signal from the base microphone is
transmitted to the line.
programmed. The ringing melody is programmed via the
microcontroller and generated by the MC34216A. The
volume can be programmed via the 3 loudspeaker gain bits
G2G1G0. The ring melody is enabled by making the ring
tone switch R T high. The melody can be tested during
normal speech mode by activating the ring tone switch R T
while R/S is low.
R/S bit high. This enables the microphone, earphone and
loudspeaker amplifiers while the set is on–hook. This makes
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The MC34216A incorporates a DTMF generator with
For listening–in operation, the loudspeaker has to be
By making the SP bit high, the speakerphone mode is
By making the R/S bit high, the ringing mode is
The answering machine mode is entered by making the
MC34216A
it possible to record a message with the handset microphone
and to playback messages via the earpiece or loudspeaker.
Other blocks of the circuit are not activated. During off–hook
operation, the incoming messages can be recorded and the
outgoing message can be played in the normal way. More
details about the answering machine application can be
found in the user manual.
Support Material
Device Specification:
User Manual MC34216A: Extended description of the circuit
Demonstration Board:
Adjustment Software:
Register Display Board:
MOTOROLA ANALOG IC DEVICE DATA
Brief description of the MC34216A,
block diagram, device data, bus
specification, test diagram, typical
application
and its concept, description of the
programmability, adjustment
procedure, application hints and
proposals
Performance of the MC34216A is
shown in an application with the
TCA3385 switched mode power
supply and a MC68HC705
microcontroller
A QBASIC program which helps
the customer to find the right
component values for fulfilling the
requirements
Visualizes the register contents
which are transmitted on the
demonstration board by means of
LEDs