Philips Semiconductors
One-chip telephone ICs with speech,
dialler and ringer functions
Product specification
UBA2050(A); UBA2051(A;C)
FEATURES
Speech/transmission part
• Low DC line voltage; operates down to 1.45 V
(excluding voltage drop over external polarity guard)
• Line voltage regulator with adjustable DC voltage
• Regulated 3.3 V supply (VDD) for the dialler part and
peripherals compatible with:
– Speech mode
– Ringer mode
– Trickle mode.
• Unregulated supply (VCC) for the transmission part and
peripherals
• Transmit stage with:
– Microphone amplifier with symmetrical
high-impedance inputs
– DTMF input with confidence tone on receive output.
• Receive stage with:
– Receive amplifier with asymmetrical output
– Earpiece amplifier with adjustable gain (and gain
boost facility) for all types of earpieces.
• AGC: line loss compensation for microphone and
receive amplifiers.
Dialler part
• Last Number Redial (LNR) (32 digits)
• Pulse dialling:
– 10 PPS and 20 PPS (resistor option)
– M/B 2 : 3 and 1 : 2 (resistor option).
• DTMF timing:
– Manual dialling with minimum duration for bursts and
pauses (85/85 ms)
– Calibrated timing during redialling (85/85 ms).
• Pulse or tone mode select at start-up (resistor option)
• Flash function (600, 300, 98 and 80 ms) (resistor
options)
• Access pause time 2.0 and 3.6 s (resistor option);
access pauses in series are possible
• [∗/T] key (for mixed mode dialling) or separate
[P → T] key
• Repertory memory integrity check
• Keytone generation (only UBA2050, UBA2050A and
UBA2051C)
• Dial Mode Output (DMO) function during pulse dialling
and flash function (only UBA2050 and UBA2051)
• LED output for DTMF dialling indication (only
UBA2050A and UBA2051A)
• Function keys:
– [LNR/P], [R] and [P → T]
– [STORE], [MEM], [M1], [M2] and [M3]
(only UBA2051, UBA2051A and UBA2051C).
• Resistor options:
– [∗/T] key definition (MMS)
– Pulse or Tone mode Selection (PTS)
– Flash Time Selection (FTSA and FTSB)
– Make/Break ratio Selection (MBS)
– Pulses Per Second (PPS)
– Access Pause Time (APT).
• 13 repertory numbers (only UBA2051, UBA2051A and
UBA2051C):
– 3 direct memories (21 digits)
– 10 indirect memories (21 digits).
• Supply and temperature independent tone output
• On-chip DTMF filtering for low output distortion
(“CEPT CS 203” compatible)
• On-chip oscillator suitable for low-cost 3.579545 MHz
quartz crystal or ceramic resonator
• Uses standard single-contact keyboard
• Keyboard entries fully debounced.
Ringer part
• Ringer input frequency discrimination
• 3-tone ringer with 4 programmable melodies (selectable
via keyboard by keys [1] to [4])
• 4-level volume control (selectable via keyboard by
keys [5] to [8]).
2000 May 19
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