AMSCO AS2533P

Data Sheet
AS2533...6
Multi-Standard CMOS Single Chip
Telephone IC with Dual Soft Clipping
®
Austria Mikro Systeme International AG
General Description
Key Features
The AS253x is a CMOS integrated circuit that contains
all the functions needed to form a high performance
electronic telephone.
❑ Line/speech circuit, LD/MF repertory dialler and
tone ringer on one 28 pin CMOS chip
❑ Operating range from 13 to 100 mA (down to 5 mA
with reduced performance)
❑ Soft clipping to avoid harsh distortion
❑ Volume control of receive signal
❑ Line loss compensation selectable by pin option
❑ Low noise (max. - 72 dBmp)
❑ Real or complex impedance
❑ NET 4 compatible
❑ LD/MF switchable dialling
❑ Pacifier tone during programming
❑ 31 digit last number redial
❑ Repertory memories (not AS2534), 4 direct/10
indirect (AS2533/6), 12 direct (AS2535)
❑ Repeat dialling by busy or engaged (not AS2535)
❑ Sliding cursor protocol with comparison
❑ Pause key for access pause or wait function
❑ 3 flash keys, 100 ms, 280 ms and 375/600 ms
❑ On chip MF filter (CEPT CS 203 compatible)
❑ Ring frequency discrimination
❑ 3-tone melody generator
The device incorporates LD/MF repertory dialling, melody
generation, ring frequency discrimination and a high
quality line/speech circuit.
A RAM is on chip for a 31 digit last number redial and
memories (not AS2534) each containing up to 21 digits/
data. The sliding cursor procedure makes the LNR
function easy to use under various PABX systems. Also
centrex keys (not AS2535) are provided.
The device incorporate a volume control for the earpiece.
The volume can be controlled by the VOL key (+ 5.4 dB)
or by the –/+ keys (+8.1 dB/-5.4 dB in 5 steps).
The versatility of the circuit is provided by pin options
and a few external components. This allows easy
adaptation to different PTT requirements.
Package
Available in 28 pin SOIC or DIP.
Block Diagramme
La
Z2
ZBAL
Z1
Lb
LI
CI
RI
LS
STB
LED
AGND
RO
CS
LINE ADAPTATION
POWER EXTRACTION
DC MASK
LINE
CURRENT
SENSE
SOFT CLIP
AGC
VDD
VDD
M2
M1
Vss
MO
AS253x
MELODY
SEQUENCER
R4
MUTE
TONE
GENERATOR
RAM
R3
DIALLER
FCI
RING
FREQUENCY
DISCRIMINATION
CONTROL
LOGIC
HS/DP
R2
R1
OSC
LLC
OSC
MFL
MODE
C1
C2
C3
C4
3.58
MHz
LLC Hi
LLC Lo
LLC Off
AGND
Rev. 7
1
KEY
PAD
July 1998
Data Sheet
AS2533...6
Pin Description
Pin #
Symbol
Function
23
24
M1
M2
Microphone Inputs
Differential inputs for the microphone (electret).
3
RO
Receive Output
This is the output for driving a dynamic earpiece with an impedance of 140 to 300 Ω.
5
AGND
Analogue Ground
This is the analogue ground for the amplifiers.
28
RI
6
STB
1
LS
Line Current Sense Input
This is the input for sensing the line current.
27
LI
Line Input
This input is used for power extraction and line current sensing.
25
CS
Current Shunt Control Output
This N-channel open drain output controls the external high power shunt transistor for the
modulation of the line voltage and for shorting the line during make period of pulse dialling.
4
VDD
Positive Voltage Supply
This is the supply pin for the circuit.
26
VSS
Negative Power Supply
8
MO
Melody Output
PDM output of the melody generator for tone ringing. Hi-Z when not active.
21
FCI
Frequency Comparator Input
This is a Schmitt trigger input for ring frequency discrimination. Disabled during off-hook.
10
HS/DP
Hook Switch Input and Dial Pulse Output
This is an I/O that is pulled high by the hook switch when off-hook and an open drain pulls
it low during break periods of pulse dialling and flash.
11
OSC
Oscillator Input
Pin for ceramic resonator (3.58 MHz). Recommended: Murata CSA 3.58MG312AM.
9
LLC
Line Loss Compensation
Select pin for line loss compensation (see also figure 4 to 7).
LLC = AGND: 20 - 50 mA
LLC = VDD: 45 - 75 mA
LLC = VSS: none.
22
LED
LED Output Driver
Output for driving an LED that will be flashing when in Programme/Mute state.
Receive Input
This is the input for the receive signal.
Side Tone Balance Input
This is the input for side tone cancellation.
Continues…
Rev. 7
2
July 1998
Data Sheet
AS2533...6
Pin Description cont´d
Pin #
Symbol
12
MODE
Function
Signalling Mode Select Input
Mode pin
Open
Function
Dialling inhibited
Row 1
Row 2
LD mode, 10 pps, 33/66 ms
LD mode, 10 pps, 40/60 ms
Row 3
Row 4
LD mode, 20 pps, 33/66 ms
LD mode, 20 pps, 40/60 ms
Row 5
Row 6
LD mode, 10 pps, 33/66 ms, Temp. MF with tone on first * key entry
MF only, 82/82 ms
Row 7
MF only, 82/160 ms
During temporary MF: 82/160 ms
20
19
18
17
R1
R2
R3
R4
Keyboard Rows
(see key arrangement in figure 2)
16
15
14
13
C1
C2
C3
C4
Keyboard Columns
(see key arrangement in figure 2)
7
CI
Complex Impedance Pin
For complex impedance a capacitor should be connected to this pin.
2
MFL
MF Level Setting
A voltage divider connected from this pin to AGND and VSS can be used to set the DTMF
level.
Selection Overview
Function
Direct memories (one-key)
Indirect memories (two-key)
Repeat dialling
LNR key
Pause insertion by LNR key
Pause (PS) key
P/M or MT key
Tone/Pulse (T/P) key
Temperary MF by * key
Centrex (A - D) keys
Volume (VOL, –/+) keys
Volume reset by off-hook
Programming of tone ringer
R3 Flash duration
Rev. 7
AS2533
4
10
yes
yes
yes
yes
P/M
yes
yes
yes
yes
yes
yes
600 ms
AS2534B
0
0
yes
yes
yes
yes
P/M
yes
yes
yes
yes
no
yes
600 ms
3
AS2534E
0
0
yes
yes
yes
yes
MT
yes
yes
yes
yes
no
no
375 ms
AS2535
12
0
no
yes
yes
no
P/M
no
yes
no
yes
yes
yes
600 ms
AS2536
4
10
yes
yes
yes
yes
P/M
yes
yes
yes
yes
no
yes
600 ms
July 1998
Data Sheet
AS2533...6
(Either VOL or +/– keys)
Keyboard Connections
Key closure, RON max. = 1 kohm
Key open, ROFF min. = 1 Mohm
C1
C2
C3
C4
R1
P/M
1
2
3
R2
4
5
6
7
R3
8
9
0
*
R4
#
R1
R2
R3
LNR
VOL
+
–
A
B
C
D
RP
PS
T/P
M1
M2
M3
M4
MR
Figure 2a (AS2533/6)
C1
C2
C3
C4
R1
P/M
1
2
3
R2
4
5
6
7
R3
8
9
0
*
R4
#
R1
R2
R3
LNR
VOL
+
–
A
B
C
D
RP
PS
T/P
For AS2534E
P/M is MT key.
Figure 2b (AS2534)
Rev. 7
4
July 1998
Data Sheet
AS2533...6
Keyboard Connections Continued
(Either VOL or +/– keys)
C1
C2
C3
C4
R1
P/M
1
2
3
R2
4
5
6
7
R3
8
9
0
*
R4
#
R1
R2
R3
LNR
VOL
+
–
M1
M2
M3
M4
M5
M6
M7
M8
M9
M10
M11
M12
Figure 2c (AS2535)
the device not operating is in a power down mode to
save current. The CS pin is pulled to VSS in order to turn
the external shunt transistor on to keep a low voltage
drop at the LS pin during make periods.
Power On Reset
The on chip power on reset circuit monitors the supply
voltage (VDD) during off-hook. When VDD rises above
approx. 1.2V, a power on reset occurs which clears the
RAM.
AC Impedance
The ac impedance of the circuit is set by external
components. The impedance can be real or complex.
The ac impedance is determined as follows:
DC Conditions
The normal operating range is from 13 mA to 100 mA.
Operating range with reduced performance is from 5 mA
to 13 mA (parallel operation). In the operating range all
functions are operational.
ZAC = 33 • Z 1
The dc value of Z1 should be 30 Ω to maintain correct dc
performance.
At line currents below 13 mA the AS253x provides an
additional slope below 4.5V in order to allow parallel
operation (see figure 13).
Return loss and side tone cancellation can be determined
independant of each other.
The dc characteristic (excluding diode bridge) is
determined by the voltage at LI and the resistor R1 at line
currents above 13 mA as follows:
Speech Circuit
The speech circuit consists of a transmit and a receive
path with dual soft clipping, mute, line loss compensation
and sidetone cancellation.
VLS = VLI + ILINE ⋅ R1
The voltage at LI is 4.5V in the normal operating range.
Transmit
The gain of the transmit path is 37 dB for 600 Ω line
termination from M1/M2 to LS (see test circuit figure 10).
During pulse dialling the speech circuit and other part of
Rev. 7
5
July 1998
Data Sheet
AS2533...6
The microphone input is differential with an input
impedance of 20 kΩ.
Line Loss Compensation
The line loss compensation is a pin option. When it is
activated, the transmit and receive gains are decreased
by 6 dB at line currents from 20 to 50 mA when LLC = AGND
and 45 to 75 mA when LLC = high (@ R1 = 30 Ω). The
line loss compensation is disabled when LLC = low (see
figure 4 and 5).
The soft clip circuit limits the output voltage at LI to 2VPEAK
(see figure 12). The attack time is 30 µs/6 dB and the
decay time is 20 ms/6 dB. When mute is active, during
dialling or after pressing the P/M key, the gain is
reduced by > 60 dB.
Dialling Functions
Receive
The gain of the receive path is 3 dB for 600 Ω line
termination (test circuit figure 10). The receive input is
the differential signal of RI and STB. When mute is active
during dialling the gain is reduced by > 60 dB. During
DTMF dialling a MF comfort tone is applied to the
receiver. The comfort tone is the DTMF signal with a
level that is -30 dB relative to the line signal.
Valid Keys
The key scanning is enabled when HS/DPN is pulled
high and VDD is above VREF. A valid key is detected from the
keyboard by connecting the appropriate row to the
column (RON < 1 kΩ). This can be done using an n x m
keyboard matrix with single contacts. Four diodes are
used to extend the number of rows (see keyboard
arrangement fig. 2). It is also possible to connect a
µcontroller to the rows and columns (see application
note AN3010).
The receive gain can be changed by pressing the
volume keys. The VOL key gives a +5.4 dB boost and
has a toggle function, i.e. repressing the key resets the
gain to default. As an alternative the +/– keys can be
used. The + key increases the gain by 8.1 dB in 3 steps
and the – key decreases the gain by 5.4 dB in 2 steps
(total range 13.5 dB). On AS2533/5 the volume is reset
to default by next off-hook and on AS2534/6 the volume
setting will remain at last setting. A POR will always reset
the volume to default.
P/M and MT Key
The P/M key (not AS2534E) is used to enter the
Programme/Mute state and the MT key for muting
(AS2534E only). Depressing the P/M key mutes the
speech circuit and the device is in programme state.
Repressing the P/M key deactivates the mute and
programme state (toggle function).The MT key works in
a similar way, but has no programme function.
The soft clip circuit limits the voltage at the receive
output (RO) to 1VPEAK (see figure 11). It prevents harsh
distortion and acoustic shock.
When programme/mute is activated, the LED indication
is turned on (flashing: 80 ms 'on' and 1 sec 'off').
Sidetone
A good sidetone cancellation is achieved by using the
following equation:
Dial Mode Selection
The default mode (LD or MF) can be selected by the
mode pin. When default LD mode is selected, a temporary
change to MF can be invoked by pressing T/P key (not
AS2535) or the * key (when mode pin = row 5, the MF
tone is generated with the first * key entry). The circuit
will revert to LD by repression the T/P key (not AS2535)
or by pressing the R (R1, R2 or R3) key or by next onhook.
ZBAL Z 2
=
ZLINE Z 1
The sidetone cancellation signal is applied to the STB
input.
When MF mode is selected by the mode pin, the circuit
can not be changed temporary to LD but will remain in
MF mode.
Z1
ZLINE
ZBAL
Centrex Keys (not AS2535)
The alphameric keys accommodate easy use of centrex
services. The A, B, C and D keys are only valid in MF
mode (including temporary MF) and are not storable.
Pressing one of these keys will invoke the appropriate
MF tones to be transmitted.
Z2
Figure 3
Side Tone Balance
Rev. 7
6
July 1998
Data Sheet
AS2533...6
The centrex keys are not stored in the RAM, and
subsequently entered digits are buffered in FIFO.
Last Number Redial
LNR is a facility that allows resignalling of the last
manually dialled number without keying in all the digits
again. The LNR is repeatable after each off-hook.
Memory Keys (not AS2534)
The keys M1 to M12 are direct memory access keys and
the MR key (AS2533/6 only) is used for abbreviated
dialling.
Memory arrangement
Storable numbers
Direct memory keys
Indirect memories
The current content of the RAM is overwritten by new
entries.
A manually entered number is automatically stored in
the LNR RAM. The capacity of the RAM is 31 digits. If a
number greater than 31 digits is entered, the LNR facility
will be inhibited (until new entries < 32 digits) and further
entries will be buffered in FIFO.
In the on chip RAM, numbers can be stored. Each
number can contain up to 21 digits (including pauses).
During programming multiple pauses can be inserted by
pressing the PS (not AS2535) or the LNR key. Each
pause inserted within the first 5 entries will automatically
be terminated after 2 seconds whereas pauses inserted
after location 5 in a digit string will halt dialling and can
be terminated manually by pressing the PS (not AS2535)
or the LNR key. The halt function allows in-dialling to an
extention on a PABX.
Pauses can be inserted by pressing the PS key (not
AS2535).
Post dialled digits, i.e. digits manually entered after LNR
has been invoked, are not stored in RAM but buffered in
FIFO.
Example (45678–123 is stored in M1, where – is a
pause/wait and 123 the extention number):
Repeat Dialling (not AS2535)
The last manually dialled number can be repeated
without going on-hook by pressing the RP key. If a
called number is engaged, pressing the RP key will
break the line for 1.6 second (to get a new dial tone) and
after a pause the number will be repeated.
off-hook, wait for dial tone
press M1 (45678 is dialled out)
await dial tone from called PABX
press PS or LNR (123 is dialled out).
The repeat function is enabled when prior to pressing
the RP key, a number has been dialled, and it can be
invoked an unlimited number of times until next on-hook.
During the 1.6 second break the device is in power down
mode to save current.
Memory dialling is cascadable. However, the content of
one memory must be dialled out before a new can be
invoked.
Sliding Cursor Procedure
To accommodate easy and uncomplicated redialling
(LNR) behind a PABX, a sliding cursor protocol is
implemented. If new entries match the previous RAM
contents, pressing the LNR key will dial out the remaining
digits.
Recall Function
A recall (R1, R2 or R3 key) activation will invoke a flash
(timed loop break), however, the R1 flash is never
executed in LD mode. R2 and R3 will be executed
independent of the mode.
If there is an error in matching, the LNR will be inhibited
until next on-hook, and the RAM will contain the new
number.
If recall is the first entry in a digit string, it will be stored
in LNR RAM when digit(s) are entered after the recall.
If the recall key is depressed after a digit string has been
entered or dialled out, the recall will not be stored but
buffered in the FIFO together with subsequently entered
digit.
Example (LNR content 912345, where 9 is access
code):
off-hook, wait for PABX dial tone
press 9 and wait for external dial tone
press LNR (12345 will be dialled out).
If pressing the recall key is not followed by digit entries,
the LNR RAM remains intact.
Tone Generator
The tone generator incorporates the DTMF tones, 3
basic frequencies for the tone ringer and pacifier tones.
After a recall a 270 ms pause will automatically be
executed.
Rev. 7
AS2533/6 AS2534 AS2535
14
0
12
4
0
12
10
0
0
7
July 1998
Data Sheet
AS2533...6
DTMF
The DTMF generator provides 8 frequencies, namely:
Low group
Digit 1-2-3-A
Digit 4-5-6-B
Digit 7-8-9-C
Digit * -0-# -D
697 Hz
770 Hz
852 Hz
941 Hz
High group
Digit 1-4-7- *
Digit 2-5-8-0
Digit 3-6-9-#
Digit A-B-C-D
1209 Hz
1336 Hz
1477 Hz
1633 Hz (not AS2535)
The procedure is ended by repressing the P/M key.
The default setting is digit 6, i.e. after a power on reset
the device will start up with repetition rate 4 and maximum
volume. If digit 0 is programmed, the tone ringer will be
turned off until next off-hook where it will turn back to the
last setting before 0. The programmed settings are
stored in the on chip RAM.
Repetition rate means that a sequence of 6 frequencies
is repeated 1, 4 or 10 times within 1 second.
The sequence of the frequencies is controlled by the
sequence register as follows:
The MF output level can be set with an external voltage
divider on pin MFL.
Voltage at pin MFL (2)
1.50 V (AGND)
1.27 V
1.15 V
1.03 V
0.90 V
0.70 V
0.54 V
0.42 V
0.30 V
0.18 V
0.00 V (VSS)
(ZLINE = 600 ohm)
Sequence
DTMF Level (Low Group)
-4.0 dBm
-5.2 dBm
-6.4 dBm
-7.6 dBm
-8.8 dBm
-10.0 dBm
-11.2 dBm
-12.4 dBm
-13.6 dBm
-14.8 dBm
-16.0 dBm
The AS2534E is fixed to default settings and can not be
programmed to other settings.
Pacifier Tone
By MF dialling the DTMF tones are provided to the
earpiece as comfort tone.
During programming a key entry is acknowledged by a
pacifier tone of 1477 Hz. The level of the pacifier tone is
approximately 60 mV at the RO output. The duration is
40 ms after every key entry in programme mode.
When terminating the programme mode with the P/M
key an acknowledge tone of 140 ms is provided. An
invalid key entry, however, will cause a termination of
the programme mode indicated by a rejection tone of 4
times 40 ms with 28 ms pauses between the tone bursts.
The preemphasis is 2.6 dB.
The MF tones are according to CEPT recommendations.
Tone Ringer (Melody/Volume)
The three basic frequencies of the melodies are:
Ring Frequency Discrimination
The ring frequency discriminator assures that only signals
with a frequency between 13Hz and 70 Hz are regarded
as valid ring signals. The time for recognising a valid ring
signal is 1/f seconds, where 'f' is the ring frequency.
F1 = 800 Hz, F2 = 1067 Hz, and F3 = 1333 Hz (± 5%).
The repetition rate and the volume of the tone ringer
melodies can be programmed by pressing P/M and #
followed by a digit as follows (not AS2534E):
Digit
1
2
3
4
5
6
7
8
9
0
Rev. 7
Repetition Rate
1 time (50 ms pause)
1 time (50 ms pause)
1 time (50 ms pause)
4 time s
4 times
4 times (default)
10 times
10 times
10 times
None
F1 F2 F3 F1 F2 F3 …
When a valid ring signal is present for 73 ms continuously,
the melody generator is activated and remains active as
long as the ring signal is present.
Volume
- 16 dB
- 7 dB
0 dB (max.)
- 16 dB
- 7 dB
0 dB (max.)
- 16 dB
- 7 dB
0 dB (max.)
Off
Once the melody generator has been started, the ring
signal is continuously monitored and the melody
generator is instantly turned on or off according to the
momentary presence of a valid or unvalid ring signal
respectively (until next POR or off-hook).
8
July 1998
Data Sheet
AS2533...6
Typical Characteristics of Line Loss Compensation
Fig. 4
(dB)
35
34
33
32
31
30
29
Tx Gain
LLC = AGND
LLC = VDD
LLC = VSS
f = 800 Hz
ZLINE = 600Ω
VLS = -10 dBm
20
DC Line
Current
30
40
50
60
70
80
(mA)
Fig. 5
(dB)
+4
+3
+2
+1
0
-1
-2
Rx Gain
LLC = AGND
LLC = VSS
f = 800 Hz
ZLINE = 600Ω
VLS = -10 dBm
VOL = 0 dB (neutral)
20
Rev. 7
LLC = VDD
30
DC Line
Current
40
50
9
60
70
80
(mA)
July 1998
–
26dB
+
–
10dB
+
+
–
0 dB
ZBAL
(10 x ZLINE)
RO
Data Sheet
SC
COMFORT
TONES
AC Model of Speech Circuit
Figure 8
Rev. 7
LLC &
VOLUME
Z LINE
80 k
STB
8k
DTMF
RI
10
300Ω
ZREF
30Ω
LI
LLC & SC
+
20 k
ZSYN
(970Ω)
CS
–
12dB
+
PRIVACY
MUTE
CI
–
23dB
+
20 k
M1
M2
32.3 x ZREF
AS2533...6
July 1998
AS2533...6
100 µF
Data Sheet
(see fig. 2)
KEY
PAD
C2
C1
100 k
MODE
56 k
LLC Hi
LLC Lo
LLC off
3.58
MHz
MFL
OSC
LLC
OSC
TONE
GENERATOR
HS/DP
AGND
CONTROL
LOGIC
10 n
FCI
RING
FREQUENCY
DISCRIMINATION
MELODY
SEQUENCER
MO
VDD
Vss
470 µF
220 k
Rev. 7
10 µF
330 k
4148
BC547
0.68 µF
5M1
2k2
100 k
18V
5V1
1M
470 k
2N5551
220 k
220 k
47 k
10 k
10V
2SA1209
BC327
R1
30 Ω
CS
For further application
information please refer to
application note AN2201.
VDD
LI
CI
LINE ADAPTATION
POWER EXTRACTION
DC MASK
SOFT CLIP
AGC
LINE
CURRENT
SENSE
RI
15 n
LS
10 µ
DIALLER
MUTE
RAM
AS253x
STB
1µ
100 µ
7k5
10 n
1k8
R5
Since the AS253x is a
component and not a complete
system, it can not be approved
as a stand alone part by the
standard bodies. Hence, full
conformance to any standards
is depending on the application
in which the AS253x is being
used, and therefore, approvals
by the standard bodies are the
responsibility of the customer
and Austria Mikro Systeme will
not have tested the product to
meet specific standards.
300Ω
The external components
might change to comply
with various national PTT
regulations and to interface
to different transducers.
AGND
LED
C3
C4
R2
R4
M1
R1
10 n
10 n
M2
RO
10 µF
300Ω
Only the components
necessary for
presenting the
complete functions of
the AS253X are
included.
1k8
1k8
2k2
Complex Impedance
(270 Ω + 750 Ω // 150 nF)
Figure 9
R3
Typical Application
11
July 1998
Data Sheet
AS2533...6
Operating Procedures
Procedure Principles
The procedures for utilizing the features of the AS253x are optimized out of consideration for the human factor in
order to:
- meet the user´s expectations
- be easy to learn and relearn
- not invoke any automatic functions which the user doesn´t expect
- protect the user from committing critial errors, e.g. dialling wrong numbers, deleting stored numbers, etc.
- be consistent, simple and usable.
The following pages describe the operating procedures for the provided features. Pressing an unvalid key or key
combination during programming will cause the device to abort the programme state. Pressing any key
combination or sequence which is not described or defined may cause the device to enter a state or mode that
does not comply with the expectation of the user. In such cases, any undesired state can be terminated at any time
by going on-hook / off-hook which will generate a functional reset.
Symbols
STATES
ENTRIES
Going off-hook
Idle (on-hook,
no ringing)
PROCESSING
X
sec
Time out (x sec.)
or
Dialling
(LD or MF)
Going on-hook
Speech mode
KEY
Pressing a key
Storing (writing
into RAM)
Privacy mute
Entering a
number
Programming
False programme
entry
TEXT
Entry according
to text
TEXT
Processing
according to text
reading from
memory
Invalid entry
TEXT
Rev. 7
State according
to text
12
July 1998
Data Sheet
AS2533...6
Programming Tone Ringer
(not AS2534E)
P/M
Programme State
Speech circuit muted
LED flashing
MR
Storing
Numbers
Digit
1
2
3
4
5
6
7
8
9
0
Repetition Rate
1 time (slow)
1 time (slow)
1 time (slow)
4 times
4 times
4 times (default)
10 times (fast)
10 times (fast)
10 times (fast)
None
#
M1-12
Any invalid key
entry will abort
programme
state
Storing
Numbers
Volume
- 16 dB
- 7 dB
0 dB (max.)
- 16 dB
- 7 dB
0 dB (max.)
- 16 dB
- 7 dB
0 dB (max.)
Off *
P/M
*) When digit 0 (tone ringer off) has been programmed,
the device will automatically return to the previous
setting (different from 0) by next off-hook.
Rev. 7
13
July 1998
Data Sheet
AS2533...6
Temporary MF
MODE pin connected
to row 1, 2, 3, 4 or 5
When MODE pin = row 5, pressing the * key
also transmits the tone by MF select.
The T/P key (not AS2535) can be used
alternatively to
the * key.
RAM
FIFO
Pressing any other
key does not
change the state.
T/P
*
D
FIFO
R
T/P
R
FIFO
T/P
*
EXIT FIFO
Rev. 7
14
July 1998
Data Sheet
AS2533...6
Storing Numbers (not AS2534)
Key entries different to the procedure will be ignored.
Exit programme mode from each state with on-hook
or with the P/M key.
P/M
Programme State
Speech circuit muted
LED flashing
#
M1-12
MR
Any invalid key
entry will abort
programme
state
Programming
Tone Ringer
Melodies
0-9
Entries (0-9, *, #, PS or LNR, R1, R2,
R3) will be written directly into the
selected memory location
P/M
Rev. 7
15
July 1998
Data Sheet
AS2533...6
Automatic Dialling
MR
M1-12
LNR
0-9
or
Postdialled digits are not stored
but buffered in FIFO
Rev. 7
16
July 1998
Data Sheet
AS2533...6
Timing Diagrammes
LD Dialling
MUTE
MASK
HS/DPN
tIDP
tB
tPDP
tB
tM
tIDP
tM
tB
t PDP
tM
LD Dialling With Access Pause
MUTE
MASK
HS/DPN
t IDP
tB
t PDP
tB
tM
t AP
tIDP
tM
tB
t PDP
tM
MF Dialling
MUTE
MASK
HS/DPN
TONE
tTD
tITP
tTD
tITP
tAP
t TD
tITP
Continues....
Rev. 7
17
July 1998
Data Sheet
AS2533...6
Flash
MUTE
MASK
HS/DPN
tM
tFD
tM
tPFP
tM
tFD
tM
Repeat Dialling (not AS2535)
Number
engaged
New
connection
RP key
MUTE
DIALLING
HS/DPN
Power
Down
tRP
Rev. 7
18
t AP
July 1998
Data Sheet
AS2533...6
Electrical Characteristics
Absolute Maximum Ratings
Positive Supply Voltage .................................................................................................................. -0.3V ≤ VDD ≤ 7V
Input Current ............................................................................................................................................... ± 25 mA
Input Voltage (LS) ......................................................................................................................... -0.3V ≤ VIN ≤ 10V
Input Voltage (LI, CS) ...................................................................................................................... -0.3V ≤ VIN ≤ 8V
Input Voltage (STB, RI) ......................................................................................................... -2V ≤ VIN ≤ VDD + 0.3V
Input Voltage (MO) ...................................................................................................................... -0.3V ≤ VIN ≤ +35V
Digital Input Voltage ............................................................................................................-0.3V ≤ VIN ≤ VDD + 0.3V
Electrostatic Discharge ................................................................................................................................ ± 1000V
Storage Temperature ..................................................................................................................... -65°C to +125°C
Recommended Operating Conditions
Supply Voltage * (Speech Mode) ....................................................................................................... 4V ≤ VDD ≤ 5V
Oscillator Frequency (Resonator: Murata CSA 3.58M G312AM) .............................................................. 3.58 MHz
Operating Temperature ................................................................................................................... - 25°C to +70°C
* This voltage is generated internally
DC Characteristics (ILINE = 15 mA unless otherwise specified)
Symbol
Parameter
Conditions
IDD
Operating Current
IDD0
Retention Current
Min
Typ
Max
Units
Speech mode
3
5
mA
MF dialling
4
mA
LD dialling, VDD = 2.5V
200
µA
Ring mode, VDD = 2.5V
300
µA
Idle mode, VDD = 2V
0.05
µA
TAMB = 25°C
VLI
Line Voltage (default)
13 mA ≤ ILINE ≤100 mA
4.5
V
IOL
Output Current, Sink
VOL = 0.4V
1.5
mA
4
mA
CS, HS/DP, MO
IOL
Output Current, Sink; LED
VOL = 0.4V
VIL
Input Low Voltage
HS/DPN; FCI
VSS
0.3 VDD
V
0.7 VDD
VDD
V
TAMB = 25°C
VIH
Input High Voltage
HS/DPN; FCI
TAMB = 25°C
Rev. 7
19
July 1998
Data Sheet
AS2533...6
AC Characteristics (ILINE = 15 mA; f = 800 Hz unless otherwise specified)
Symbol
Parameter
Conditions
Tx
Transmit
Test Circuit Fig. 10
ATX
Gain, Transmit
M1/M2 to LI
∆ATX/F
Variation with Frequency
f = 500 Hz to 3.4 kHz
THD
Distortion
VLI ≤ 0.25VRMS
VAGC
Soft Clip Level
VLI =
ASCO
Min
Typ
Max
Units
35.1
36.6
38.1
dB
±0.8
dB
2
%
2
VPEAK
Soft Clip Overdrive
20
dB
tATTACK
Attack Time
30
µs/6 dB
tDECAY
Decay Time
20
ms/6dB
ZIN
Input Impedance (M1/M2)
20
kΩ
AMUTE
Mute Attenuation
Mute activated
VNO
Noise Output Voltage
TAMB = 25°C
VIN Max
Input Voltage Range
Differential
(M1/M2)
Single Ended
60
dB
-72
dBmp
±1
VPEAK
±0.5
VPEAK
BJT
Output Driver
VIN MAX
Input Voltage Range (LI)
±2
VPEAK
VTX
Dynamic Range
±2
VPEAK
RL
Return Loss
∆ZAC/TEMP
Temperature Variation
Rx
Receive
ARX
Receive Gain (Vol. default) LI to RO
AVOL
Volume Gain
VOL key
+5.4
dBr
AVOL
Volume Gain
–/+ keys
-5.4/+8.1
dBr
∆ARX/F
Variation with Frequency
f = 500 Hz to 3.4 kHz
±0.8
dB
THD
Distortion
VRI ≤ 0.25VRMS
VAGC
Soft Clip Level
VRO =
ASCO
Soft Clip Overdrive
tATTACT
Attact Time
tDECAY
Decay Time
VNO
Noise Output Voltage
TAMB = 25°C
-72
dBmp
VUFC
Unwanted F. Components
50 Hz....20 kHz
-60
dBm
ZIN
Input Impedance (RI)
8
kΩ
VIN RI
Input Voltage Range (RI)
±2
VPEAK
AST
Sidetone Cancellation
VIN ST
Input Voltage Range (STB)
±2
VPEAK
ZIN
Input Impedance (STB)
80
kΩ
Rev. 7
ZRL=1000Ω; TAMB = 25°C
18
dB
Ω/°C
0.5
Test Circuit Fig. 10
1.5
3
4.5
2
VRI > 0.8VRMS
VRI ≤ 0.25VRMS
%
1
VPEAK
10
dB
30
µs/6 dB
20
ms/6dB
26
20
dB
dB
July 1998
Data Sheet
AS2533...6
AC Characteristics (cont´d) (ILINE = 15 mA; f = 800 Hz unless otherwise specified)
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Keyboard
tD
Key Debounce Time
15
ms
HS/DPN Input
tHS-L
Low to High Debounce
Going off-hook
15
ms
tHS-H
High to Low Debounce
Not LD dialling
210
ms
During LD dialling
270
ms
DTMF
F
Frequency deviation
Note 5
VMF
MF Tone Level (Low group) MFL = AGND
MFL = VSS
1.2
%
- 2.5
-4
- 5.5
dB
- 14.5
- 16
- 17.5
dB
1.8
2.4
3.0
dB
∆VL-H
Preemphasis Low to High
VUFC
Unwanted F. Componets
300 Hz...5 kHz
-40
dBm
Note 3; MFL = VSS
5 kHz...14 kHz
-50
dBm
14 kHz...28.5 kHz
-70
dBm
28.5 kHz...40 kHz
-80
dBm
tTD
Tone Duration
Note 1&6; Mode=row 6 or 7
80
82.3
85
ms
tITP
Inter Tone Pause
Note1; Mode=row 6
80
82.3
85
ms
tITP
Inter Tone Pause
Note 1 & 6; Mode=row 7
150
165
170
ms
tTR
Tone Rise Time
Note 2
5
ms
tTF
Tone Fall Time
Note 2
5
ms
LD
tDR
Dial Rate
Mode = row 1, 2 or 5
9.53
10
10.5
pps
Mode = row 3 or 4
19.05
20
21
pps
t/B
Break Period
Mode = row 2
57
61.2
63
ms
t/B
Break Period
Mode = row 4
28.5
30.6
31.5
ms
t/B
Break Period
Mode = row 1 or 5
63
66
69
ms
t/B
Break Period
Mode = row 3
31.5
33
34.5
ms
tM/
Make Period
Mode = row 2
38
40.8
42
ms
tM/
Make Period
Mode = row 4
19
20.4
21
ms
tM/
Make Period
Mode = row 1 or 5
31.5
33
34.5
ms
tM/
Make Period
Mode = row 3
15.7
16.5
17.3
ms
tPDP
Pre-Digit Pause
tIDP
Inter Digit Pause
Mode = row 1, 2, 3, 4 or 5
tHS-H
High to Low Debounce
During LD dialling
tMO
Mute Overhang
Rev. 7
35
800
840
270
ms
880
ms
ms
tM
21
July 1998
Data Sheet
AS2533...6
Symbol
Parameter
Conditions
Min
tFD
Flash Duration 1
R1 key
Flash Duration 2
Flash Duration 3
tPFP
Post Flash Pause
tAP
Access Pause
tRP
Repeat Break Time
Typ
Max
Units
100
102
ms
R2 key
270
300
ms
R3 key (AS2533/4B/5/6)
600
650
ms
R3 key (AS2534E only)
312
450
ms
375
274
Note 8
2.0
2.05
ms
2.12
1.6
sec
sec
Tone Ringer
VMO
Melody Output
PDM
tMD
Melody Delay
F1
Frequency 1
800
Hz
F2
Frequency 2
1067
Hz
F3
Frequency 3
1333
Hz
tDT
Detection Time
1/f + 73ms
s
tTO
Detection Time-out
note 4
ms
fMIN
Min. Detection Frequency
13
Hz
fMAX
Max. Detection Frequency
70
Hz
1477
Hz
10
Initial
ms
Pacifier Tone
Programme Mode Only
fPT
Frequency
P/M mode, key entry
VRT
Level (RO)
Key entry
60
mV
tRTD-E
Duration, Key Entry
Valid key entry, prog.
40
ms
tRTD-A
Duration, Acknowledge
Terminate with P/M key
140
ms
tRTD-R
Duration, Reject
Invalid key entry, note 7
4x40
ms
LED Output
tLED-ON
"on-time"
P/M state
80
ms
tLED-OFF
Interval
P/M state
1
sec
-30
dBr
Comfort Tone (DTMF)
VCT
Level (RO)
Relative to LS
Note 1: The values are valid during automatic dialling and are minimum values during manual dialling, i.e. the tones will
continue as long as the key is depressed.
Note 2: The rise time is the time from 10% of final value till the tone amplitude has reached 90 % of its final value.
Note 3: Relative to high group.
Note 4: The FCI circuit is reset by POR and HS/DPN pulled high (off-hook). After a reset the FCI circuit is in a standby state. A
positive edge on FCI will start a 73 ms timer and the frequency discrimination is initiated. Whenever a period of the ring
signal is missing, the timer is reset. When a valid ring signal is present for 73 ms, the melody generator is started and is
directly controlled by the ring signal. This condition will remain until a new reset.
Note 5: This does not include the frequency deviation of the ceramic resonator.
Note 6: During temporary MF mode.
Note 7: An invalid key entry in programme mode will invoke a tone sequence with 4 tone bursts of 40 ms and pauses between
bursts of 28 ms and abort the programme mode.
Note 8: Pauses inserted within the first 5 entries of a digit string will be automatically terminated after 2 seconds. Pauses
inserted after location 5 can only be terminated manually by pressing the PS or LNR key.
Rev. 7
22
July 1998
Rev. 7
ILINE
B
10V
BC 327
10 n
30 Ω
300 Ω
10 µ
6k
3.58 MHz
1µ
23
9
7
11
10
2
26
25
27
6
28
1
LLC
CI
OSC
HS/DP
MFL
Vss
CS
LI
STB
RI
LS
FCI
AS253x
UL
600 Ω
100 µ
A
21
VDD
MO
MODE
R4
R3
R2
R1
C4
C3
C2
C1
AGND
LED
RO
M2
M1
4
8
12
17
18
19
20
13
14
15
16
5
22
3
24
23
5V6
22 µ
100 µ
150 Ω
100 µ
Data Sheet
AS2533...6
Test Circuit
MULTI-STANDARD
SINGLE CHIP TELEPHONE
Figure 10
July 1998
Data Sheet
AS2533...6
Characteristic Curves (Typical)
Fig. 11 Receive Soft Clipping and Distortion
12
1,2
soft clipping
(Vp)
2,5
11
(%)
VRO
1,0
10
(%)
9
soft clipping
(Vp)
10
VLS
2,0
8
0,6
8
7
6
5
0,4
4
THD
3
2
0,2
7
Line Current: 20 mA
Frequency
Tamb: 25°C
Typically
1,5
6
5
1,0
Distortion
Line Current: 20 mA
Frequency: 800 Hz
Tamb: 25°C
Typically
0,8
Line Output Voltage (LS)
9
Distortion
Receive Output Voltage (RO)
Fig. 12 Transmit Soft Clipping and Distortion
4
THD
0,5
3
2
1
0,0
0,00
1
0
0,25
0,50 0,75 1,00 1,25 1,50
Line Input Voltage (LS)
1,75 2,00
(Vp)
0,0
0
25
50
75
100
0
125 (mVp) 150
Microphone Input Voltage (M1/M2)
Fig. 13 DC Mask
(V)
8
VLS
7
6
VLI
5
4
Typically
No ac signals
Tamb: 25°C
3
2
1
0
0
Rev. 7
10
20
30
40
Line 50
Current 60
24
70
80
90 (mA) 100
July 1998
Data Sheet
AS2533...6
28 Pin DIP (suffix P)
28 Pin SOIC (suffix T)
1
2
28
27
3
4
5
26
25
24
STB
CI
6
7
8
MO
LLC
HS/DP
OSC
MODE
C4
C3
9
10
11
12
AS253x
LS
MFL
RO
VDD
AGND
13
14
LS
MFL
RO
VDD
AGND
STB
CI
MO
LLC
HS/DP
OSC
MODE
C4
C3
RI
LI
VSS
CS
M2
23
22
21
M1
LED
FCI
20
19
18
17
R1
R2
16
15
C1
C2
R3
R4
1
28
2
27
3
26
4
25
5
24
6
7
8
9
10
AS253x
Pin Configuration
23
22
21
20
19
11
18
12
17
13
16
14
15
RI
LI
VSS
CS
M2
M1
LED
FCI
R1
R2
R3
R4
C1
C2
Ordering Information
Device
AS2533 T
AS2533 P
AS2534B T
AS2534B P
AS2534E P
AS2534E T
AS2535 T
AS2535 P
AS2536 T
AS2536 P
Package
28 pin SOIC
28 pin DIP
28 pin SOIC
28 pin DIP
28 pin DIP
28 pin SOIC
28 pin SOIC
28 pin DIP
28 pin SOIC
28 pin DIP
Memories
4 direct/10 indirect
4 direct/10 indirect
none
none
none
none
12 direct
12 direct
4 direct/10 indirect
4 direct/10 indirect
Volume
yes, note 1
yes, note 1
yes, note 2
yes, note 2
yes, note 2
yes, note 2
yes, note 1
yes, note 1
yes, note 2
yes, note 2
Centrex
ABCD
ABCD
ABCD
ABCD
ABCD
ABCD
no
no
ABCD
ABCD
Special keys
P/M, LNR, R1-3, MR, RP, PS, T/P
P/M, LNR, R1-3, MR, RP, PS, T/P
P/M, LNR, R1-3, RP, PS, T/P
P/M, LNR, R1-3, RP, PS, T/P
MT, LNR, R1-3, RP, PS, T/P
MT, LNR, R1-3, RP, PS, T/P
P/M, LNR, R1-3
P/M, LNR, R1-3
P/M, LNR, R1-3, MR, RP, PS, T/P
P/M, LNR, R1-3, MR, RP, PS, T/P
Conditions for delivery as dice see also data sheet AS2533/4B/5/6-CX.
Note 1: volume is reset to default by on-/off-hook and by POR
Note 2: volume is reset by POR only.
Application:
For application support contact your local sales offices.
Devices sold by Austria Mikro Systeme/Thesys are covered by the warranty and patent idemnification provisions appearing in its Term of Sale. Austria Mikro Systeme/Thesys makes no warranty,
express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the decribed devices from patent infringement. Austria Mikro Systeme reserves
the right to change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with Austria Mikro Systeme for current
information. This product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability
applications, such as military, medical life-support or life-sustaining equiment are specifically not recommended without additional processing by Austria Mikro Systeme/Thesys for each application.
Copyright © 1995-8, Austria Mikro Systeme International AG, Schloss Premstätten, 8141 Unterpremstätten, Austria. Trademarks Registered ®. All rights reserved. The material herein may not be
reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner.
The information furnished here by Austria Mikro Systeme/Thesys is believed to be correct and accurate. However, Austria Mikro Systeme/Thesys shall not be liable to recipient or any third party
for any damages, including but not limited to personal injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or consequential damages, of any
kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of Austria Mikro
Systeme/Thesys‘ rendering of technical or other services.
Rev. 7
25
July 1998