MC33218ADWR2 Freescale Semiconductor, MC33218ADWR2 Datasheet - Page 26

• Manufacturer Part Number: MC33218ADWR2
• Description: IC VOICE SWITCH SPKPHONE 24-SOIC
• Manufacturer: Freescale Semiconductor

Specifications of MC33218ADWR2

• Function: Voice-Switched Speakerphone
• Interface: SPI Serial
• Voltage - Supply: 2.7 V ~ 6.5 V
• Current - Supply: 4.6mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: *
• Includes: Chip Disable
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Power (watts): -
• Number Of Circuits: -
• Other names: MC33218ADWTR

communication signal, usually expressed in dB.
frequencies of a communication system.
the telephone from the CO. The name derives from the fact
that COs have always used batteries, in conjunction with AC
power, to provide this voltage.
evaluates the effects of noise on a typical subscriber’s
system.
office, usually within of a few miles of its subscribers, that
houses switching gear for interconnection within its
exchange area, and to the rest of the telephone system. A
CO can handle up to 10,000 subscriber numbers.
converts the transmit signal to digital, and converts the digital
receive signal to analog.
another power or voltage. It is generally computed as:
600 , or 0.775 Vrms, is defined as 0 dBm. Any other voltage
level is converted to dBm by:
psophometric weighting filter.
power level into 600
measurements, 0 dBrn = – 90 dBm.
C–message weighting filter.
system based on outputting two non–harmonic related
frequencies simultaneously to identify the number dialed.
Eight frequencies have been assigned to the four rows and
four columns of a keypad.
office, which operates on two pairs of wires. One pair is for
the Transmit path, and one pair is for the Receive path.
communication in both directions simultaneously. The
standard handset telephone system is full duplex.
decrease) after passing through an amplifier, or other circuit
stage. Usually expressed in dB, an increase is a positive
number, and a decrease is a negative number.
communication in one direction at a time. CB radios, with
“ p u s h – t o – t a l k ” s w i t c h e s , a n d v o i c e a c t i v a t e d
speakerphones, are half duplex.
connects the telephone circuit to the subscriber loop. The
name derives from old telephones where the switch was
activated by lifting the receiver off and onto a hook on the side
of the phone.
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A t t e n u a t i o n – A d ec r e as e in mag nit u de o f a
Bandwidth – The range of information carrying
Battery – The voltage which provides the loop current to
C–Message Filter – A frequency weighting which
Central Office – Abbreviated CO, it is a main telephone
CO – See Central Office.
CODEC – Coder/Decoder – In the Central Office, it
dB – A power or voltage measurement unit, referred to
for power measurements, and
for voltage measurements.
dBm – An indication of signal power. 1.0 mW across
d B m p – I ndi c at es dB m m ea s ur em en t us i n g a
dBrn – Indicates a dBm measurement relative to 1.0 pW
dBrnC – Indicates a dBrn measurement using a
DTMF – Dual Tone MultiFrequency. It is the “tone dialing”
Four Wire Circuit – The portion of a telephone, or central
Full Duplex – A transmission system which permits
Gain – The change in signal amplitude (increase or
Half Duplex – A transmission system which permits
Hookswitch – A switch, within the telephone, which
10 x log (P 1 /P 2 )
20 x log (V 1 /V 2 )
dBm = 20 x log (Vrms/0.775), or
dBm = [20 x log (Vrms)] + 2.22.
. Generally used for noise
Freescale Semiconductor, Inc.
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MC33218A
DEFINITIONS
transmit and receive signals are absent.
which connects to the subscriber’s phone line. A line card
may hold circuitry for one subscriber, or a number of
subscribers.
circuit to reject longitudinal signals on Tip and Ring.
and Ring) connected to the telephone at one end, and the
central office (or PBX) at the other end. Generally it is a
floating system, not referred to ground, or AC power.
subscriber loop. It is typically provided by the central office or
PBX, and ranges from 20–120 mA.
that it is inaudible. Partial muting is used in some
applications.
connected to the phone system, permitting the loop current to
flow. The central office detects the DC current as an
indication that the phone is busy.
disconnected from the phone system, and no DC loop
current flows. The central office regards an on hook phone as
available for ringing.
miniature central office, it is a customer owned switching
system servicing the phones within a facility, such as an
office building. A portion of the PABX connects to the Bell (or
other local) telephone system.
reject outputting noise, or ripple, which is present on the
power supply lines. PSRR is usually expressed in dB.
blocks or gas discharge tubes, it absorbs the bulk of a
lightning induced transient on the phone line by clamping the
voltages to less than 1500 V.
telephone, it protects the phone circuit from transient surges.
Typically, it must be capable of clamping a 1.5 kV surge of
1.0 ms duration.
is interrupted a number of times in quick succession. The
number of interruptions corresponds to the number dialed,
and the interruption rate is typically 10 per second. The old
rotary phones, and many new pushbutton phones, use pulse
dialing.
from the phone line (Tip and Ring) towards the receiver or
speaker.
impedance, or loading factor, of a telephone bell or ringer
circuit. An REN of 1.0 equals
typically permits a maximum of 5.0 REN (1.6 k ) on an
individual subscriber line. A minimum REN of 0.2 (40 k ) is
required by the Bell system.
Hybrid – A two–to–four wire converter.
Idle Channel Noise – Residual background noise when
Line Card – The pc board, and circuitry, in the CO or PBX
Longitudinal Balance – The ability of the telephone
Longitudinal Signals – Common mode signals.
Loop – The loop formed by the two subscriber wires (Tip
Loop Current – The DC current which flows through the
Mute – Reducing the level of an audio signal, generally so
Off Hook – The condition when the telephone is
On Hook – The condition when the telephone is
PABX – Private Automatic Branch Exchange. In effect, a
Power Supply Rejection Ratio – The ability of a circuit to
Protection, Primary – Usually consisting of carbon
Protection, Secondary – Usually located within the
Pulse Dialing – A dialing system whereby the loop current
Receive Path – Within the telephone it is the speech path
REN – Ringer Equivalence Number. An indication of the
MOTOROLA ANALOG IC DEVICE DATA
8.0 k . The Bell system