ams AS2525B Single-chip handsfree phone cmos integrated circuit Datasheet

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austriamicrosystems
Single-Chip Handsfree Phone
CMOS Integrated Circuit
AS2525
DATA SHEET
Key Features
-
Package
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The AS2525 is a CMOS mixed-mode integrated circuit for
use in feature phones, answering machines and fax
machines. It contains an analogue line interface and
speech circuit for a/b terminals, loudhearing, handsfree,
enhanced LD/MF dialler, tone ringer with dc/dc converter
and serial interface to EEPROM and LCD-driver (AS2591),
all in a 44 pin package. The circuit is fully line powered.
lv
-
Line/speech handsfree circuit, LD/MF repertory dialler,
and tone ringer on one 44 pin CMOS chip
Operating range from 15 to 100 mA line current (down
to 5 mA with slightly reduced performance)
All significant parameters programmable with external
EEPROM
Volume control of receiver signal
Handsfree function with enhanced voice switching
Low noise (max. -72 dBmp)
Unique EMC performance
LD/MF switchable dialing with temporary MF mode
Repertory dialing with last number redial and memory
dialing (8 x 2 direct and 12 indirect)
Call restriction with PIN code
Serial interface for EEPROM and LCD driver
2-tone/3-tone ringer with ring frequency detection
The AS2525 uses an external EEPROM for a 32 digit last
number redial storage and memories for 28 numbers each
containing up to 24 digits/data.
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General Description
The device provides a volume control for the earpiece and
the loudspeaker. The volume can be controlled by pressing
the [V-]/[V+] keys.
The versatility of the circuit is provided by programming all
parameters through an external EEPROM. This allows easy
adaptation to various PTT requirements worldwide.
Available in 44 pin TQFP.
Block Diagram
LS
30 Ω
LI
AS2525
VDD
FT2
AGND
VDD
LINE
SENSE
CBN
FT1
M1
AGND
VREF
SUPPLY
NOISE
DET.
+
VDD
M2
CS
+
M3
ca
–
–
SS
VPP
AGND
PEAK
DET.
–
VSS
+
VOICE
SWITCHING
VPP
CI
PEAK
DET.
300 Ω
ch
RI
STB
Te
ZBAL
LO2
+
VSSA
RECI
RECV
DTMF
MELODY
DEBOUNCE
DM/HM
RO
FCI
DPN
CPU
DIALLER
KEYSCANNING
LED
DI DO CLK
Revision 2.1
LO1
–
HS
HF
VDD
M4
VPP
ni
VSS
+
CS1 CS2
KEYBOARD (C1-4/R1-3)
OSCILLATOR
3.58
MHz
DC/DC
CONVERTER
CM
Page 1 of 27
austriamicrosystems
Datasheet AS2525
Pin Description
Pin #
Symbol
Type
1
CS2
DO
Description
C hip S elect 2
Chip select signal for external LCD driver circuit or 2 mA LED
If signal is not activated, a pull down resistor (100 kΩ) is inserted.
DPn
DO
D ial P ulse Output
al
id
2
Digital output that holds the line during off-hook operation or pulls low during break periods
of pulse dialing and flash.
3
HF
DI
H ands F ree Switch Input
4
HS
DI
H and S et Switch Input
lv
This is a Schmitt-trigger input that is pulled high to enable handsfree operation.
This is a Schmitt-trigger input that is pulled high by the hook switch to enable handset or
headset operation.
FT1
6
FT2
7
M4
AI
Analogue input pin for connecting a capacitor for offset cancellation.
AI
Analogue input pin for connecting a capacitor for offset cancellation.
AI
M icrophone Input 4
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5
Differential input for the handsfree microphone (electret).
8
M2
AI
M icrophone Input 2
Differential input for the handset microphone (electret).
9
M3
AI
M icrophone Input 3
Differential input for the handsfree microphone (electret).
10
M1
AI
M icrophone Input 1
Differential input for the handset microphone (electret).
11
STB
AI
S ide T one B alance Input
Analogue input for side tone cancellation network.
12
CS
AO
C urrent S hunt Control Output
13
V SS
ca
N-channel open drain output to control the external high power shunt transistor for
synthesizing ac- and dc-impedance, modulation of line voltage and shorting the line during
make periods of pulse dialing.
Supply
V oltage S ource S ource
Negative Power Supply.
LI
AI
L ine I nput
ni
14
Analogue input used for power extraction and line current sensing.
RI
ch
15
Te
16
17
18
SS
LS
AI
R eceive I nput
Analogue input for ac-separated receive signal.
AO
S upply S ource Control Output
N-channel open drain output to control the external high power source transistor for
supplying (Vpp) the loudspeaker amplifier in off-hook loudspeaking/handsfree mode.
AI
L ine Current S ense Input
Analogue input for sensing the line current.
CI
AI
C omplex I mpedance Input
Analogue input pin for the capacitor to program a complex impedance.
Revision 2.1
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Datasheet AS2525
Pin #
Symbol
Type
19
RECI
AI
Description
REC eive I nput
Analogue input for the handsfree receive path. Should be connected to RO via a coupling
capacitor.
20
RECV
AI
REC eive V oice Switching Input
Analogue input for receive voice switching path.
21
RO
AO
R eceive O utput to H andset
22
V DD
Supply
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Output for driving a dynamic earpiece with an impedance from 150 Ω to 300 Ω .
V oltage D rain D rain
Positive Power Supply.
A GND
Supply
A nalogue G rou nd
Special ground for the internal amplifiers.
lv
23
24
CBN
AI
Analogue input pin for connecting a capacitor for background noise monitoring.
25
CM
DO
C onverter M ake Output
26
V PP
27
28
LO1
LO2
29
V SSA
30
DM/HM
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This is an output for controlling the external switching converter. During ringing it converts
the ring signal into a 4V supply voltage.
Supply
AO
Loudspeaker Power Supply
High power supply for the output driver stage.
L oudspeaker O utputs 1/2
Output pins for a 32 Ω ( 25 to 50 Ω ) loudspeaker.
Supply
DI
Power supply pin for LO1-LO2 output amplifier.
D ial M ode/ H eadset M ode Switch Input
Digital input for choosing between LD and MF dialing or choosing handset and headset
mode. See “Table 3: Parameter settings” for further details. This pin is scanned after manual
off-hook only.
31
FCI
DI
F requency C omparator I nput
This is a Schmitt-trigger input for ring frequency discrimination. Disabled during off-hook.
32
LED
DO
LED Output
Digital output for connecting 2 mA LED to indicate handsfree mode.
OSC
Osc illator Input
ca
33
Input for ceramic resonator 3.58 MHz.
Te
41
42
DI/O
Keyboard
R ows
(see Figure 1: Keyboard Layout).
C1
C2
C3
C4
DI/O
CLK
DO
ch
37
38
39
40
R1
R2
R3
ni
34
35
36
Keyboard
C olumns
(see Figure 1: Keyboard Layout).
Cl oc k
Clock output for 3-wire bus.
If signal is not activated, a pull down resistor (100 k Ω ) is inserted.
DI
DI
D ata I nput
Data input of 3-wire bus.
If signal is not activated, a pull down resistor (100 k Ω ) is inserted.
Revision 2.1
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Datasheet AS2525
Pin #
Symbol
Type
43
DO
DO
Description
D ata O utput
Data output of 3-wire bus.
A 100 k Ω resistor connected from this pin to VSS enables key locking.
If signal is not activated, a pull down resistor (100 k Ω ) is inserted.
44
CS1
DO
C hip S elect 1
If signal is not activated, a pull down resistor (100 k Ω ) is inserted.
Digital Input
Digital Output
Digital Input/Output
AI:
AO:
AI/O:
Analogue Input
Analogue Output
Analogue Input/output
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DI:
DO:
DI/O:
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Chip select signal for external EEPROM.
Basic Definitions
Password is set to 0123 and is used to access basic
parameter settings (see Table 3: Parameter settings). The
set-up programming is normally done in the factory during
manufacturing of the telephone sets. The factory settings
can be loaded into the EEPROM (see Figure 3: Memory
allocation for external EEPROM).
PIN code is default set to 1111 and is used by the user to
protect certain user settings (see Table 5: User
programming with PIN code). The PIN code can be
changed by the user.
Default settings are shown in bold.
C1
C2
C3
1
2
3
MR
V+
M1
4
5
6
PG
VM2
7
8
9
R/P
MT
M3
M5
M6
M7
C4
∗
0
#
FL
SH
R1
R2
R3
M4
M8
Figure 1: Keyboard Layout
Maximum R ON for key closure: 1 k Ω
Minimum R OFF for open key: 1 M Ω
See “Table 1: Key definitions” for description of key
functions
Te
ch
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Program procedures are entered with the [PG] key.
Pressing any invalid key or going on-hook during
programming will abort the program mode and no changes
will be stored. Ending a program procedure by pressing the
[PG] key will store the changes and exit the program mode.
Keyboard Layout
Revision 2.1
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Datasheet AS2525
Key Definitions and Procedures
Table 1: Key definitions
Key
Condition
Function
Remark
Off-hook
Digits
Function depending on mode
[∗]
LD mode
Temporary MF select
Providing mixed mode dialing (default LD selected)
Speech mode
Enter program state
To enter the program state
Program mode
Exit program state
To terminate/exit program state
Speech mode
Enter mute state
To enter mute state
Mute state
Exit mute state
To terminate/exit mute state
Program mode
Enter blank
To enter blank digit during programming
Redial/Pause
Allows re-signaling of the last dialed number and
insertion of pauses
[R/P]
Program state
[FL]
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[MT]
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[PG]
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[0] - [9],
[#], [∗]
Pause
Each key pressure inserts a pause
Flash function
Invokes a timed loop break
[V+]
Speech mode
Volume control
To increase the receive gain
[V-]
Speech mode
Volume control
To increase or decrease the receive gain
Memory redial key
To access memory by key codes
Memory dial
Access keys to memories 1 to 8 and 9 to 16
Second function (shift)
To access second function of keys
[MR]
[M1] - [M8]
[SH]
Table 2: Digits
Digit Key
DTMF Mode
(f LOW + f HIGH )
Pulse Mode
[0]
941 + 1336 Hz
10 pulses
[1]
697 + 1209 Hz
1 pulse
[2]
697 + 1336 Hz
[3]
[4]
Programming Mode
([PG] + Digit)
Memory Location
([MR] + Digit)
Memory 17
Memory 18
2 pulses
Select flash duration
Memory 19
697 + 1477 Hz
3 pulses
Select dialing mode
Memory 20
770 + 1209 Hz
4 pulses
Select pause duration
Memory 21
770 + 1336 Hz
Key lock toggle
Memory 22
5 pulses
[6]
ni
ca
To enter PIN protected programming
770 + 1477 Hz
6 pulses
Ringer volume
Memory 23
[7]
852 + 1209 Hz
7 pulses
Ringer melody
Memory 24
[8]
852 + 1336 Hz
8 pulses
LCD contrast
Memory 25
[9]
852 + 1477 Hz
9 pulses
Ringer on/off
Memory 26
[∗]
941 + 1209 Hz
Temporary MF select
-
[#]
941 + 1477 Hz
-
-
Te
ch
[5]
Revision 2.1
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Datasheet AS2525
Table 3: Parameter settings
Procedure:
[PG] + [0] + (Password) +
Inter-Digit Pause (LD)
IDP
[∗] + [1] + [HEX code]
840 ms
1.72 ms … 7.03 sec. (see Table 4)
MF Tone Duration
TD
[∗] + [2] + [HEX code]
82 ms
1.72 ms … 7.03 sec. (see Table 4)
MF Inter-Tone Pause
ITP
[∗] + [3] + [HEX code]
82 ms
1.72 ms … 7.03 sec. (see Table 4)
Flash 1 Duration
FL1
[∗] + [4] + [HEX code]
101 ms
1.72 ms … 7.03 sec. (see Table 4)
Flash 2 Duration
FL2
[∗] + [5] + [HEX code]
285 ms
1.72 ms … 7.03 sec. (see Table 4)
Pause 1 Duration
P1
[∗] + [6] + [HEX code]
1 second
1.72 ms … 7.03 sec. (see Table 4)
Pause 2 Duration
P2
[∗] + [7] + [HEX code]
3 seconds
1.72 ms … 7.03 sec. (see Table 4)
Pre-Digit Pause (LD)
PDP
[∗] + [8] + [HEX code]
33 ms
1.72 ms … 7.03 sec. (see Table 4)
Post Flash Pause
PFP
[∗] + [9] + [HEX code]
274 ms
1.72 ms … 7.03 sec. (see Table 4)
Tx Gain, Handset
Default
Options
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Parameter
A TX-HS
[0] + [1] + [HEX code]
37 dB
30 to 45 dB (see Table 8)
A RX-HS
[0] + [2] + [HEX code]
1 dB
-6 to 9 dB (see Table 12)
A TX-HF
[0] + [3] + [HEX code]
46 dB
39 to 54 dB (see Table 10)
Rx Gain, Loudspeaker
A RX-HS
[0] + [4] + [HEX code]
29 dB
22 to 37 dB (see Table 14)
Line Loss Compensation
LLC
[0] + [5] +
[0] = off
[1] = range 1: I LINE = 20 - 50 mA
[2] = range 2: I LINE = 45 - 75 mA
DTMF Level (Low Group)
V MF
[0] + [6] + [HEX code]
-6 dBm
-18 to -6 dBm in 1 dB steps
(see Table 24)
Tx Gain, Headset
A TX-HEAD
[0] + [7] + [HEX code]
37 dB
30 to 45 dB (see Table 20)
A RX-HEAD
[0] + [8] + [HEX code]
1 dB
-6 to 9 dB (see Table 21)
V MF-CT/RO
[0] + [9] + [HEX code]
-30 dBr
-36 to -18 dBr in 6 dB steps
(see Table 30)
V MF-CT/LO
[0] + [0] + [HEX code]
-9 dBr
-15 to 3 dBr in 6 dB steps
(see Table 30)
Rx Gain, Handset
Tx Gain, Handsfree
Rx Gain, Headset
MF Comfort Tone, RO
ca
MF Comfort Tone, LO1/2
M/B
[#] + [1] +
[1] = 2 : 3
[0] = 1 : 2
Dial Rate (LD)
DR
[#] + [2] +
[0] = 10 pps
[1] = 20 pps
[#] + [3] +
[1] = 4.5 Volt
[0] = 3.5 Volt
Tx Soft Clip (Handset)
[#] + [4] +
[1] = on
(2 V PEAK )
[0] = off
Rx Soft Clip (Handset)
[#] + [5] +
[1] = on
(1 V PEAK )
[0] = off
Noise Monitoring (HF)
[#] + [6] +
[1] = on
[0] = off
Loudhearing Mode
[#] + [7] +
[1] = HF only
[0] = LH and HF modes available
Ringer Melody
[#] + [8] +
[1] = 3-Tone
[0] = 2-Tone
[#] + [9] +
[1] = on
[0] = off
[#] + [0] +
[1] = 1111
Selected by user
ni
Make/Break Ratio (LD)
V LI
Te
ch
DC Mask (LI Voltage)
Key-in Tone (Beep)
Reset PIN Code
Revision 2.1
KT
Page 6 of 27
austriamicrosystems
Datasheet AS2525
Parameter
Symbol
Procedure:
[PG] + [0] + (Password) +
Default
Options
[#] + [∗] +
[1] = on
[0] = off
Flash 2 During LD
[#] + [#] +
[0] = off
[1] = on
Extended LCD Symbols
[9] + [1] +
[0] = off
[1] = on
Tx Soft Clip, Handsfree
[9] + [2] +
[1] = on
[0] = off
Rx Soft Clip, Handsfree
[9] + [3] +
[1] = on
[0] = off
Voice Switching, Speed
[9] + [4] +
[1] = x 2
[0]=x1 (slow); [2]=x4; [3]=x8 (fast)
Handset/Headset Volume
[9] + [5] +
[1] = reset by
on/off-hook
[0] = setting is maintained
LCD Test
[9] + [6]
Turns on all segments, pressing any further key turns
on all digits “1” and all symbols off.
Temporary MF by * with
tone
[9] + [7] +
[0] = off
Key Lock Function
[9] + [8] +
[1] =
available
[0] = not available
[9] + [9] +
[1] = MF/LD
[0] = Handset/Headset
[9] + [0] +
[1] =
available
[0] = not available
[9] + [∗] +
Any key pressure turns the LED on
[9] + [#] +
[1] = enabled
Ringer Off Function
Key Test
Volume Control on
Handset
DM/HM
The above parameters are programmable using a password
(0123) through external EEPROM. All procedures must be
terminated by pressing the [PG] key. Software for factory
settings is available on request.
4
5
6
7
8
9
Te
3
0
A (M1) B (M2) C (M3) D (M4)
E (M5) F (M6)
lv
[0] = disabled
Data = 4096 - (f OSC / (512 * 12) * T
(T = Time; f OSC = 3.58 MHz)
Table 4: Timing selection by HEX code
Parameter
Default
HEX
Binary Data
Inter-digit pause
840 ms
E17
1111 0001 0111
Tone duration
82 ms
FD0
1111 1101 0000
R1
Inter-tone pause
82 ms
FD0
1111 1101 0000
R2
Flash 1
101 ms
FC4
1111 1100 0100
R3
Flash 2
285 ms
F5A
1111 0101 1010
Pause 1
1 sec
DB9
1101 1011 1001
Pause 2
3 sec
92C
1001 0010 1100
Pre-digit pause
33 ms
FED
1111 1110 1101
Post-flash pause
274
F60
1111 0110 0000
C4
ni
C3
ch
1
2
C2
ca
The programming of timings is done by using a HEX data
code as follows:
C1
[1] = on
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Pin Select “DM/HM”
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Flash 1 During LD
Figure 2: Keys for HEX-code entry
Revision 2.1
Page 7 of 27
austriamicrosystems
Datasheet AS2525
Table 5: User programming with PIN code
Function
Symbol
Procedure
Options
CR1
[PG] + [1] + (PIN) + [∗] + [1] +
Key in two digits, use [MT] for blank
Call Restriction 2
CR2
[PG] + [1] + (PIN) + [∗] + [2] +
Key in two digits, use [MT] for blank
Key Lock
[PG] + [1] + (PIN) + [#] + [6] +
[0] = unlocked and [1] = locked
Clear All Memories
[PG] + [1] + (PIN) + [#] + [7] +
Press [1] to clear
Reset To Factory
Settings
[PG] + [1] + (PIN) + [#] + [8] +
Press [1] to reset
[PG] + [1] + (PIN) + [0] +
Key in new PIN + new PIN
Change PIN Code
PIN
Table 6: Mode programming
Select Flash
Select Dialing Mode 1
Select Pause Time
Easy Key Lock 2
Ringer Volume
Ringer Melody
LCD Contrast
Bell On/Off
Symbol
Procedure
Options
FL
[PG] + [2] +
[0] = Flash 1 and [1] = Flash 2
DM
[PG] + [3] +
[0] = LD (pulse) and [1] = MF (DTMF)
P
[PG] + [4] +
[0] = Pause 1 and [1] = Pause 2
[PG] + [5] + [3] + [9]
Toggles between locked and unlocked
[PG] + [6] +
[1] = -16 dB, [2] = -7 dB, and [3] = 0 dB (maximum)
[PG] + [7] +
[0], [1], [2], [3], or [4]
[PG] + [8] +
[1], [2], or [3] (see also AS2591 data sheet)
[PG] + [9] +
[0] = Off and [1] = On
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Function
lv
Press [PG] to store setting and terminate procedure
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Call Restriction 1
V 33
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Press [PG] to store setting and terminate procedure
1
2
Only when DM/HM pin is set to HM
Also selectable with jumper (see application note AN525)
Revision 2.1
Page 8 of 27
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Datasheet AS2525
Memory Allocation
The EEPROM memory consists of three areas:
A = factory settings; B = user settings; C = stored numbers
EEPROM
programmed in factory
"reset to factory settings"
B) user settings
User-code programming
C) stored numbers
lv
…write/read by AS2525
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Figure 3: Memory allocation for external EEPROM
The AS2525 is writing and reading to and from area B and
C during normal operation and user-code programming.
Area A is protected during normal operation and contains a
back-up copy of the factory settings. This back-up copy
can be loaded into area B by the user with the user-code
programming procedure "reset to factory settings". The
only way to change the factory settings in area A is by setup programming using password. After changing area A by
set-up programming, the AS2525 automatically performs a
"reset to factory settings" to load this changes also into
area B.
Functional Description
DC Conditions
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Set-up programming
A) factory settings
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The normal operating mode is from 15 mA to 100 mA. An
operating mode with reduced performance is from 5 mA to
15 mA. In the line-hold range from 0 mA to 5 mA the device
is in a power down mode.
The dc characteristic is determined by the voltage at LI pin
ch
and a 30 Ω resistor between pin LI and LS. It can be
calculated by the following equation:
V LS = V LI + I LINE * 30 Ω
Te
VLI can be programmed to be 3.5 V or 4.5 V.
VLine
8
(V)
VLS
6
4
VLI
2
0
0
20
40
ILine
60
80
(mA)
100
Figure 4: DC characteristic with low dc mask
2/4 Wire Conversion
AS2525 has a built-in dual Wheatstone bridge with one
common ground. This provides a maximum of
independence of ac impedance and side-tone from each
other. One can adapt side-tone without changing the ac
impedance.
AC Impedance
The ac impedance of AS2525 is set to 1000 Ω . A complex
impedance can be adjusted by connecting an external
capacitor to the CI pin. With an external resistor of
approximately 1.5 k Ω connected to the LS pin, it can be
programmed to 600 Ω .
Z AC(syn) = 33 ∗ 30 Ω
Table 7: DC mask selection
[PG] + [0] + (Password) + [#] + [3] + (digit) + [PG]
Digit
[0]
[1]
Revision 2.1
DC Mask (dc voltage at pin LI)
Low dc mask, VLI = 3.5 Volt
High dc mask, VLI = 4.5 Volt
Page 9 of 27
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Datasheet AS2525
Table 10: Handsfree Tx gain setting
A good side-tone cancellation can be achieved by using
the following equation:
Z BAL /Z LINE = 10
This is assuming that the side-tone reference resistor, R2
(between LI and STB) is 300 Ω and R1 is 30 Ω .
R1 = 30 ohm
ZLINE
[PG] + [0] + (Password) + [0] + [3] + (x) + [PG]
Key
(x)
Tx Gain (dB)
M3/4 to LS
Key
(x)
Tx Gain (dB)
M3/4 to LS
[0]
[1]
[2]
[3]
[4]
[5]
[6]
[7]
39
40
41
42
43
44
45
46
[8]
[9]
[M1]
[M2]
[M3]
[M4]
[M5]
[M6]
47
48
49
50
51
52
53
54
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Side-Tone
The input is differential with an impedance of 10 k Ω .
ZBAL
lv
R2 = 300 ohm
The soft clip circuit limits the output voltage swing at pin
Figure 5: Side-tone balance
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Transmit Path
LS to 2 V PEAK when activated .
Table 11: Handsfree Tx soft clipping selection
The gain of the M1/M2 —> LS path is default set to 37 dB.
This gain can be changed from 30 dB to 45 dB in 1 dB
steps by set-up programming.
Table 8: Handset Tx gain setting
[PG] + [0] + (Password) + [0] + [1] + (x) + [PG]
Tx Gain (dB)
M1/2 to LS
Key
(x)
Tx Gain (dB)
M1/2 to LS
[0]
[1]
[2)
[3]
[4]
[5]
[6]
[7]
30
31
32
33
34
35
36
37
[8]
[9]
[M1]
[M2]
[M3]
[M4]
[M5]
[M6]
38
39
40
41
42
43
44
45
ca
Key
(x)
ni
The input is differential with an impedance of 10 k Ω . The
soft clip circuit limits the output voltage swing at pin LS to
2 V PEAK when activated.
Table 9: Handset Tx soft clipping selection
ch
[PG] + [0] + (Password) + [#] + [4] + (digit) + [PG]
Digit
Handset Tx Soft Clipping
Disabled
Enabled (2 V PEAK )
Te
[0]
[1]
There is optional LLC for this path.
The gain of the M3/M4 —> LS path is default set to 46 dB.
This gain can be changed from 39 dB to 54 dB in 1 dB
steps by set-up programming.
Revision 2.1
[PG] + [0] + (Password) + [9] + [2] + (digit) + [PG]
Digit
[0]
[1]
Handsfree Tx Soft Clipping
Disabled
Enabled (2 V PEAK )
There is no LLC option for this path.
Receive Path
The gain of the LS —> RO receive path is default set to 1
dB. This gain can be changed from -6 dB to 9 dB in 1 dB
steps by set-up programming.
Table 12: Handset Rx gain setting
[PG] + [0] + (Password) + [0] + [2] + (x) + [PG]
Key
(x)
Rx Gain (dB)
LS to RO
Key
(x)
Rx Gain (dB)
LS to RO
[0]
[1]
[2]
[3]
[4]
[5]
[6]
[7]
-6
-5
-4
-3
-2
-1
0
1
[8]
[9]
[M1]
[M2]
[M3]
[M4]
[M5]
[M6]
2
3
4
5
6
7
8
9
When the handset volume control is enabled (see Table 3:
Parameter settings), the user can also change the gain
within this range in 4 dB steps via the [V+]/[V-] keys. The
default receive gain in handset and headset mode must lie
between position 5 and 9 for correct operation of the
volume control. The receive input is the differential signal
of RI and STB. The soft clip circuit limits the output voltage
at RO to 1 V PEAK . It prevents harsh distortion and acoustic
shock.
Page 10 of 27
austriamicrosystems
Datasheet AS2525
Table 13: Handset Rx soft clipping selection
Table 16: Line loss compensation selection
[PG] + [0] + (Password) + [#] + [5] + (digit) + [PG]
Digit
[0]
[1]
Handset Rx Soft Clipping (Earpiece)
[PG] + [0] + (Password) + [0] + [5] + (digit) + [PG]
Digit
[0]
[1]
[2]
Disabled
Enabled
There is LLC option for this path.
LLC Range
No LLC (gain independent of line current)
-1 dB/5 mA from 20 to 50 mA
-1 dB/5 mA from 45 to 75 mA
When it is activated, the transmit and receive gains for
both channels are decreased by 6 dB at line currents from
20 mA to 50 mA or from 45 mA to 75 mA depending on
selected range.
This gain can be changed by set-up programming from 22
dB to -37 dB in 1 dB steps.
Handsfree
[PG] + [0] + (Password) + [0] + [4] + (x) + [PG]
Rx Gain (dB)
LS to LO1/2
Key
(x)
Rx Gain (dB)
LS to LO1/2
[0]
[1]
[2]
[3]
[4]
[5]
[6]
[7]
22
23
24
25
26
27
28
29
[8]
[9]
[M1]
[M2]
[M3]
[M4]
[M5]
[M6]
30
31
32
33
34
35
36
37
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Key
(x)
The handsfree function allows voice communication without
using the handset (full 2-way speaker phone). Two voice
controlled attenuators prevent acoustic coupling between
the loudspeaker and the handsfree microphone.
lv
Table 14: Loudspeaker gain setting
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The gain of the LS —> LO1/LO2 receive path is set to 29
dB.
The user can also change the gain using the [V+]/[V-] keys
(see section "Handsfree"). The volume range is 20 dB (8
steps, each 2.5 dB).
The voice switching circuit has three states, namely idle,
transmit or receive. In receive mode the attenuation of the
receive path and the transmit path can be controlled by the
volume keys between 0 dB and -20 dB. The following table
(Table 18: Handsfree attenuation scheme) shows how
voice switching is controlled.
voice switching circuit
TX_atten
RX
Voice
switching
speech
Backgnd
noise
monitor
The receive input is the differential signal of RI and STB.
The soft clip circuit limits the output voltage swing at
LO1/LO2 to 1 V PEAK .
ca
Table 15: Loudspeaker soft clipping selection
Figure 6: Handsfree voice switching
[PG] + [0] + (Password) + [9] + [3] + (digit) + [PG ]
[0]
[1]
Handsfree Rx Soft Clipping (Loudspeaker)
A background monitoring circuit is incorporated. This
Disabled
Enabled
circuit can be enabled/disabled as required .
ni
Digit
ch
There is optional LLC for this path.
Line Loss Compensation (LLC)
Te
The line loss compensation is set-up programmable and
effects only the handset mode.
Revision 2.1
Table 17: Background noise monitoring selection
[PG] + [0] + (Password) + [#] + [6] + (digit) + [PG]
Digit
[0]
[1]
Background Noise Monitoring
Disabled
Enabled
Page 11 of 27
austriamicrosystems
Datasheet AS2525
Gmax = +9dB
Gmin = -21dB … -40dB (VOL)
LINE
+23dB
+14dB
+8dB
+3dB
Offset
comp
Compress
Peak
detector
speech
Voice
switching
FT2
CTXoffset
Peak
detector
Compress
RO
Offset
comp
FT1
Peak
detector
CBckgnd
RECI
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Compress
Gmax = -4dB … +16dB (VOL)
Gmin = -33dB
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Figure 7: Signal path of handsfree circuit
+12dB
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RECV
Offset
comp
Cmicoffset
CBN
Table 18: Handsfree attenuation scheme
RX > TX_atten
TX_atten > RX
TX_atten > RX
Speech
Mode
RX-gain
TX-gain
Remark
X
Receive
0 dB to -20 dB
-50 dB to -30 dB
adjustable with [V+]/[V-] keys in 8 steps
No
Idle
-25 dB
-25 dB
middle position
Yes
Transmit
-50 dB
0 dB
independent of [V+]/[V-] keys
IDLE-mode
RX-mode
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0dB
Vol default
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Vol max
-10dB
TX-mode
TX-gain
-20dB
Vol min
-25dB
-30dB
-40dB
RX-gain
-50dB
Figure 8: Gain transition of voice switching
Revision 2.1
Page 12 of 27
austriamicrosystems
Datasheet AS2525
Loudhearing
A loudhearing mode can be enabled/disabled through the
set-up programming.
Table 19: Loudhearing mode selection
[PG] + [0] + (Password) + [#] + [7] + (digit) + [PG ]
[0]
[1]
Loudhearing
Ring Frequency Detection
Enabled (LH + HF provided)
Disabled (only HF is provided)
The ring frequency detector assures that only signals with
a frequency between 13 Hz and 70 Hz are regarded as
valid ring signals.
Headset mode
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Digit
If this mode is entered both hook inputs HS and HF act as
electronic off-hook for handset operation. The gain in
transmit and receive can be programmed by service code
programming. The pin "HEAD" is only scanned once after
off-hook and any change on this pin during one session will
be ignored.
When a valid ring signal is present for 100 ms
continuously, the melody generator is activated and
remains active as long as the ring signal is present.
Table 20: Headset Tx gain setting
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 invalid ring signal respectively (until
next POR or off-hook).
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Head set mode is selected by connecting pin "HEAD" to
VDD and enabling the head function by service code
programming (see also Table 3: Parameter settings).
[PG] + [0] + (Password) + [0] + [7] + (x) + [PG]
Key
(x)
Tx Gain (dB)
M1/2 to LS
Key
(x)
Tx Gain (dB)
M1/2 to LS
[0]
[1]
[2]
[3]
[4]
[5]
[6]
[7]
30
31
32
33
34
35
36
37
[8]
[9]
[M1]
[M2]
[M3]
[M4]
[M5]
[M6]
38
39
40
41
42
43
44
45
DC/DC converter
When a valid ring signal is detected, the dc/dc converter is
started.
Table 21: Headset Rx gain setting
[PG] + [0] + (Password) + [0] + [8] + (x) + [PG]
Rx Gain (dB)
LS to RO
Key
(x)
Rx Gain (dB)
LS to RO
[0]
[1]
[2]
[3]
[4]
[5]
[6]
[7]
-6
-5
-4
-3
-2
-1
0
1
[8]
[9]
[M1]
[M2]
[M3]
[M4]
[M5]
[M6]
2
3
4
5
6
7
8
9
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Key
(x)
Revision 2.1
Page 13 of 27
austriamicrosystems
Datasheet AS2525
Dialing and Control Functions
Example 1:
Prohibit all calls with numbers starting with 0.
Valid Keys
The key scanning is enabled in off-hook mode with V DD
above V REF . A valid key is detected from the keyboard by
connecting the appropriate row to the column (R ON < 1
kΩ). This can be done using an n x m keyboard matrix with
single contacts. Three diodes and a resistor are used to
extend the number of rows (see Figure 1: Keyboard
Layout).
Activate: [PG] + [1] + (PIN) + [1] + [0] + [PG]
Deactivate: [PG] + [1] + (PIN) + [1] + [MT] + [PG]
Example 2:
A PIN code is available for protecting various user
settings. The default PIN code is set to 1111 and can be
change as follows:
Activate: [PG] + [1] + (PIN) + [1] + [0] + [PG] + [PG] + [2] +
(PIN) + [1] + [9] + [PG]
Deactivate: [PG] + [1] + (PIN) + [1] + [MT] + [PG] + [PG] +
[2] + (PIN) + [1] + [MT] + [PG]
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2. Press [1] + (PIN) + [0]
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1. Press [PG] to enter program mode
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PIN Code
Prohibit all calls with numbers starting with 09 (numbers
starting with 00…, 01…, etc. will be allowed; pauses will be
ignored, i.e. numbers starting with 0 PS 9 … will be
prohibited).
3. Key in new PIN code (valid digits: 0 - 9, #)
4. Key in new PIN code again
5. Press [PG] (= store and exit) or go on-hook to
abort
It is also possible to reset the PIN code through set-up
programming:
1. Press [PG] to enter program mode
2. Press [0] + (Password) + [#] + [0]
Pressing the [MT] key in place of the digit during
programming will cancel said call restriction. The first and
second digit can be stored, changed or deleted
independent of each other.
Key Lock
A key lock function is provided to allow the user to protect
the telephone from any misuse. When this function is
available through the set-up programming, it is possible to
enable/disable the key lock using the user PIN code.
3. Press [1] to reset
4. Press [PG] (= store and exit) or go on-hook to
abort
1. Press [PG] to enter program mode
2. Press [1] +(PIN) + [#] + [6]
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Call Restriction
Enabling/disabling key lock:
ch
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A call restriction function is accommodated. This function
can be activated using the PIN code. One or two digits can
be programmed to inhibit dialing starting with said digit(s).
If first digit(s) of a manual entered number or a number
retrieved from a memory matches the content of the call
restriction memory, dialing will be inhibited.
Storing digits for call restriction:
Te
1. Press [PG] to enter program mode
2. Press [1] + (PIN) + [∗]
3. Press [1] for entering first digit of call restriction
or [2] for entering second digit
3. Press [1] for enable or [0] for disable
4. Press [PG] (= store and exit) or go on-hook to
abort
Also an easy key lock function is provided. This function
can be activated/deactivated when the key lock function is
available through set-up programming and the previous
mentioned key lock through PIN code is disabled.
Clear Memory Procedure
It is possible to clear all stored numbers by using the PIN
code as follows:
1. Press [PG] to enter program mode
4. Key in digit for call restriction
2. Press [1] + (PIN) + [#] + [7]
5. Press [PG] (= store and exit) or go on-hook to
abort.
3. Press [1] for clear
Revision 2.1
Page 14 of 27
austriamicrosystems
Datasheet AS2525
Reset to Factory Settings
It is possible to reset all settings to the default factory
settings with following procedure:
1. Press [PG] to enter program mode
2. Press [1] + (PIN) + [#] + [8]
3. Press [1] for reset
4. Press [PG] (= store and exit) or go on-hook to
abort
Flash Function
A flash, [FL] key, activation will invoke a timed loop break.
The flash duration can be programmed through set-up (see
Figure 2: Keys for HEX-code entry and Table 4: Timing
selection by HEX code):
Table 22: Flash duration setting
[PG] + [0] + (Password) + [∗
∗ ] + (digit) + (HEX) + [PG]
Digit
[4]
[5]
Timing
Flash Duration
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4. Press [PG] (= store and exit) or go on-hook to
abort
HEX code
HEX code
Flash 1
Flash 2
One of two pre-programmed can be selected as follows:
1. Press [PG] to enter program mode
The default signaling mode (LD or MF) is selectable
through following procedure:
2. Press [2] to enter flash select mode
3. Press [0] for duration 1 and [1] for duration 2
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1. Press [PG] to enter program mode
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Dial Mode Selection
2. Press [3] to enter dial select mode
3. Press [0] for LD and [1] for MF
4. Press [PG] (= store and exit) or go on-hook to
abort
When default LD mode is selected, a temporary change to
MF can be invoked by pressing the [∗
∗ ] key. Temporary MF
select with tone on first key pressure can be selected as
option (see also Table 3: Parameter settings). The circuit
will revert to LD by pressing the [FL] key or by next onhook.
Re-Dialing (Last Number Redial)
ca
Re-dialing is a facility that allows re-signaling of the last
dialed number without keying in all the digits again.
Numbers dialed out from any memory will also be stored in
the LNR memory. The re-dialing works in following manner:
Any digit (including Flash, Pause, and MF select) being
dialed is storable in the LNR memory up to a total of 31
digits.
-
If more than 31 digits are entered, re-dialing will be
inhibited.
ch
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-
Pressing the [R/P] key as first entry after off-hook
(LNR cursor at first digit) will invoke dialing the content
of the LNR memory.
Te
-
-
If the [R/P] key is pressed after entering one or more
digits, the key will function as a pause key and each
pressure will insert a pause.
Pauses can also be inserted by pressing the [R/P] key in
program mode.
Revision 2.1
4. Press [PG] (= store and exit) or go on-hook to
abort
A flash entered will be stored in the LNR memory together
with entered digits. After a recall a 270 ms pause will
automatically be executed.
Pauses
Pauses can be inserted if the [R/P] key is pressed after
entering one or more digits. Also during programming,
pauses can be inserted by pressing the [R/P] key. Default
pause duration is 1 second (P1) and an alternative pause
of 3 second (P2) can be selected. These pauses can be
changed through the set-up programming (see Table 3:
Parameter settings)
Memory Keys
The keys [M1] to [M8] are direct memory access keys,
[SH] key is used to access second level of direct
memories, and the [MR] key is used for key-code dialing.
Up to 26 numbers can be stored in the on-chip RAM. Each
number can contain up to 21 digits (including pauses).
During programming multiple pauses can be inserted by
pressing the [RD] key.
Example (45678P123 is stored in M1, where P is a pause
and 123 the extension number):
1. Off-hook, wait for dial tone
2. Press [M1]
45678 is dialed out
- Dialing halts (pauses)
- Dialing is resumed, 123 is dialed out.
-
Memory dialing is cascadable up to a the maximum of 31
digits/data.
Page 15 of 27
austriamicrosystems
Datasheet AS2525
Up to 28 numbers, each with maximum 24 digits, can be
stored into the external EEPROM. The store procedure is
as follows:
1. Press [PG] to enter program mode
2. Enter location (MR + digit 3 ; M1 to 8; or
SH + M1 to 8)
3. Enter number
4. Press [PG] to store and exit or go on-hook to abort
5. Go to 1 for storing further numbers
[R/P]
Digit
Ringer Melody
2-tone
3-tone
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DTMF
The DTMF generator provides 7 frequencies.
Table 23: DTMF frequencies
Digit
Frequency
Rows
1-2-3
4-5-6
7-8-9
Low Group
697 Hz
770 Hz
852 Hz
941 Hz
∗-0-#
Columns
High Group
1209 Hz
1-4-7-∗
2-5-8-0
3-6-9-#
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Digit
[PG] + [0] + (Password) + [0] + [6] + (x) + [PG]
Level (dBm)
Low Group
Key
(x)
Level (dBm)
Low Group
-18
-17
-16
-15
-14
-13
-12
[7]
[8]
[9]
[M1]
[M2]
[M3]
-11
-10
-9
-8
-7
-6
Sequence
Rate
[PG] + [7] +
[0]
F1 F2 F3 F1 F2 F3
1
[1]
F1 F2 F3 F1 F2 F3
2
[2]
F1 F2 F3 F1 F2 F3
4
[3)
F1 F2 F3 F1 F2 F3
6
[4]
F1 F2 F3 F1 F2 F3
10
Press [PG] to store and terminate
The chosen melody will be heard in the loudspeaker during
programming. Pressing the [PG] key will end the procedure
and the last selected melody will be stored.
When 2-tone melody is selected through the set-up
procedure, it is possible to chose the following melodies:
Table 27: 2-tone melody programming
[PG] + [7] +
Table 24: DTMF level settings
ch
Procedure
Procedure
1336 Hz
1477 Hz
The MF output level can be set through set-up programming. The range is from -18 dBm to -6 dBm in 1 dB steps.
Te
[PG] + [0] + (Password) + [#] + [8] + (digit) + [PG]
Table 26: 3-tone melody programming
The tone generator incorporates the DTMF tones, 3
frequencies for the tone ringer and pacifier tones.
3
Table 25: Basic ringer melody selection
The user can chose the following melodies as shown in
below table.
Tone Generator
[0]
[1]
[2]
[3]
[4]
[5]
[6]
The tone ringer incorporates two basic selection, namely 2tone or 3-tone melodies. The default set-up selection is the
3-tone ringer.
[0]
[1]
starts and stops security storing
(LCD-Symbols [ and ])
inserts a pause (LCD-Symbol P)
Key
(x)
Tone Ringer (Melody/Volume)
lv
[Mute]
The pre-emphasis is 2.6 dB. The DTMF tones are
according to CEPT recommendations.
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Memory Storing Procedure
Digit
Sequence
[0]
F1 F2
[1]
F1 F2
[2]
F1 F3
[3)
F1 F3
[4]
F2 F3
Press [PG] to store
F1 F2 F1 F2
F1 F2 F1 F2
F1 F3 F1 F3
F1 F3 F1 F3
F2 F3 F2 F3
and terminate
Rate
2
5
2
5
2
Repetition rate means that a sequence of 6 frequencies is
repeated 1, 2, 4, 5, 6 or 10 times within 1 second.
Pacifier Tone
Any key entry is acknowledged by a pacifier tone (key-in
tone) of 1333 Hz. The pacifier tone can be
enabled/disabled through set-up programming.
Digit includes 0 – 9, ∗ and #
Revision 2.1
Page 16 of 27
austriamicrosystems
Datasheet AS2525
Table 28: Pacifier tone selection
Serial Bus
[0]
[1]
Pacifier Tone (Key-in Tone)
Disabled
Enabled
Table 29: Pacifier tones
Key Entry
Acknowledge
Reject/Terminate
Frequency
Duration
1333 Hz
1333 Hz
40 ms
4 x 40 ms
An invalid key entry will be indicated by a rejection tone of
4 times 40 ms.
[PG] + [0] + (Password) + [0] + (y + x) + [PG]
+
+
+
+
Level (dBr)
Earpiece
[0]
[1]
[2]
[3]
-36
-30
-24
-18
-
reading and writing to the external EEPROM under
following conditions:
Table 31: EEPROM read/write timings
ACTION
After
After
After
After
After
DURATION
off-hook (debounced)
on-hook (debounced)
first rising edge at FCI
PG is terminated
pressing [V+]/[V-]
Key
(y + x)
[0]
[0]
[0]
[0]
+
+
+
+
50 ms
200 ms
10 ms
12…600 ms
20 ms
Level (dBr)
Loudspeaker
[0]
[1]
[2]
[3]
-15
-9
-3
3
LCD Control
The AS2525 is designed to work together with the LCD
driver AS2591 (see also AS2591 data sheet).
Te
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[9]
[9]
[9]
[9]
sending data to the LCD driver (AS2591) when a key is
pressed or a number is dialed out
See also AS2591 data sheet for further information.
Table 30: DTMF comfort tone level setting
Key
(y + x)
-
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By MF dialing the DTMF tones are provided to the earpiece
as comfort tone. The level of the comfort is selected
through the set-up programming.
The AS2525 incorporates a microwire™ compatible serial
bus (DO, DI, and CLK) with two chip select outputs (CS1
and CS2). The serial bus is used to:
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Digit
lv
[PG] + [0] + (Password) + [#] + [9] + (digit) + [PG]
Revision 2.1
Page 17 of 27
austriamicrosystems
Datasheet AS2525
Electrical Characteristics
Absolute maximum ratings
-0.3 ≤ V DD ≤ 7V
Positive Supply Voltage
Input Current
+/- 25 mA
-0.3V ≤ V IN ≤ 12V
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Input Voltage (LS)
-0.3V ≤ V IN ≤ 8V
Input Voltage (LI, CS)
-2V ≤ V IN ≤ V DD +0.3V
Input Voltage (STB, RI)
-0.3V ≤ V IN ≤ V DD + 0.3V
Digital Input Voltage
+/- 1000V
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Electrostatic Discharge
Storage Temperature Range
-65 to +125°C
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Total Power Dissipation
500mW
* Exceeding these figures may cause permanent damage. Functional operation under these conditions is not permitted.
Recommended Operating Range
Symbol
Parameter
Min.
Conditions
V DD
Supply Voltage (internally generated)
T AMB
Ambient Operating Temp. Range
f OSC
Oscillator Frequency
Speech mode
Max.
Units
3.0
5.0
V
-25
+70
°C
Resonator: Murata CSA 3.58M
G312AM
Typ.*
3.58
MHz
* Typical figures are at 25°C and are for design aid only; not guaranteed and not subject to production testing.
DC Characteristics
(I LINE = 15 mA, recommended operating conditions unless otherwise specified)
I DD-EXT
Operating Supply Current
ni
I DD
Typ.
Max.
Units
Speech mode
4
6
mA
Handsfree mode
11
13
mA
LD dialing, V DD = 2.5V
200
µA
Ring mode, V DD = 2.5V
300
µA
Parameter
Conditions
Min.
ca
Symbol
Speech mode or MF dialing
I DD0
Idle Current
Idle mode, V DD = 2 V, T AMB = 25°C
V LI
Line Voltage, LIVolt = 0
13 mA< I LINE < 100 mA
Te
ch
Available Supply Current for
Peripheral Circuits
Line Voltage, LIVolt = 1
2
mA
2
µA
3.2
3.5
3.8
V
4.2
4.5
4.8
V
I OL
Output Current, Sink
Pin CS, SS
V OL = 0.4V
V IL
Input Low Voltage
T AMB = 25°C
V SS
0.3 V DD
V
V IH
Input High Voltage
T AMB = 25°C
0.7 V DD
V DD
V
Revision 2.1
1
mA
Page 18 of 27
austriamicrosystems
Datasheet AS2525
AC Electrical Characteristics
I LINE = 15 mA; f = 800 Hz; ZAC = 1000 Ω ; recommended operating conditions and default settings unless otherwise specified.
Transmit
A TX
Parameter
Transmit Gain, default
Conditions
Min.
Typ.
Max.
Units
M1/M2 to LS
34.3
35.8
37.3
dB
M3/M4 to LS
42.0
44.0
46.0
dB
Variation with Frequency
f = 500 Hz to 3.4 kHz
THD
Distortion
V LS < 0.25 V RMS
V AGC
Soft Clip Level
V LS =
A SCO
Soft Clip Overdrive
t DECAY
Attack Time
t DECAY
Decay Time
100
ms/6dB
Input Impedance; M1/M2
10
kΩ
Input Impedance; M3/M4
10
kΩ
A MUTE
V NO
V IN MAX
Noise Output Voltage
T AMB = 25°C, handset mode
A TX = 37 dB
Input Voltage Range; M1/M2
and M3/M4
Differential
Parameter
Test Conditions
dB
70
µs/6dB
-72
+/- 1
Min.
ca
Dynamic Range; LI
RL
Return Loss
Typ.
Max.
dB
dBmp
V PEAK
Units
+/- 2
V PEAK
+/- 2
V PEAK
18
dB
0.5
Ω/°C
Te
ch
ni
Temperature Variation
Z RL = 1000 Ω ; T AMB = 25°C
V
20
60
Input Voltage Range; LI
V TX
%
lv
Mute activated
Symbol
∆Z AC/TEMP
2
2
Mute Attenuation
Line Driver
V IN MAX
dB
am
lc s
on A
te G
nt
st
il
Z IN
+/- 0.8
al
id
Symbol
Revision 2.1
Page 19 of 27
austriamicrosystems
Datasheet AS2525
Receive
Symbol
A RX
Parameter
Receive Gain, Default
Conditions
Min.
Typ.
Max.
Units
LS to RO; volume reset
-2.0
-0.5
1.0
dB
LS to LO1/LO2; volume max.
25.0
27.0
29.0
dB
Volume Control Range
8 steps through [V-]/[V+] keys
∆A RX
Variation with Frequency
f = 500 Hz to 3.4 kHz
THD
Distortion, RO
V RO = 0.25 V RMS
Distortion, LO1/LO2
V LO1/2 = 0.25 V RMS
V AGC
Soft Clip Level
V RO =
A SCO
Soft Clip Overdrive
t DECAY
Attack Time
t DECAY
Decay Time
V NO
Noise Output Voltage, RO
T AMB = 25°C, A RX = 3 dB
-72
dBmp
V UFC
Unwanted Frequency
Components
50 Hz.........20 kHz
-60
dBmp
Z IN
Input Impedance, RI
V IN-MAX RI
Input Voltage Range, RI
A ST
Side Tone Cancellation
Z IN
Input Impedance, STB
V IN-MAX ST
Input Voltage Range, STB
Symbol
Parameter
Key Debounce Time
t HS-L
Low/High Debounce
t HS-H
High/Low Debounce
ni
ca
td
Flash Duration
ch
t FD
Post Flash Pause
t AP
Access Pause
Te
t PFP
Revision 2.1
dB
+/- 0.8
dB
1
%
5
%
V PEAK
lv
10
2
V RI > 0.8 V RMS
V RI < 0.25 V RMS
Conditions
µs/6dB
100
ms/6dB
8
kΩ
+/- 2
V PEAK
26
Min.
dB
70
am
lc s
on A
te G
nt
st
il
General Timings
15
al
id
A RX-VOL
dB
80
kΩ
+/- 2
V PEAK
Typ.
Max.
Units
15
ms
HS Input (going off-hook)
15
ms
HS Input (going on-hook)
210
ms
FL 1 (default)
100
FL 2 (default)
275
285
102
ms
300
ms
274
P1 (default)
P2 (default)
0.9
1.0
3.0
ms
1.1
sec.
sec.
Page 20 of 27
austriamicrosystems
Datasheet AS2525
DTMF
Conditions
DF
Frequency Deviation
Deviation of ceramic resonator
is not included
V MF
MF Tone Level at LS
(Low Group)
Default
V MF-RANGE
MF Tone Level Range at LS
(Low Group)
13 steps
∆V L_H
Pre-emphasis, Low to High
V UFC
Unwanted Frequency
Components
Min.
-4.5
Typ.
-5.5
-18/-6
2.0
300 Hz....4.3 kHz
4.3 kHz…7 kHz
7 kHz....10 kHz
10 kHz…14 kHz
14 kHz....28.5 kHz
28.5 kHz....40 kHz
2.6
Max.
Units
1.2
%
-6.5
dBm
dBm
al
id
Parameter
3.2
dBr
-40
-46
-52
-58
-70
-80
dBm
dBm
dBm
dBm
dBm
dBm
am
lc s
on A
te G
nt
st
il
lv
Symbol
t TD
Tone Duration, Minimum
Default
80
82.3
85
ms
t ITP
Inter Tone Pause, Min.
Default
80
82.3
85
ms
t TR
Tone Rise Time
From 10% to 90% amplitude
5
ms
t TR
Tone Fall Time
From 90% to 10% amplitude
5
ms
V CT
Comfort Tone Level, RO
Relative to LS, 4 steps
LD Dialing
Symbol
t DR
Parameter
Dialing Rate
Conditions
Default
-36
-18
Min.
Typ.
Max.
Units
9.53
10
10.5
pps
ni
Break Period
Default
20
57
61.2
63
pps
ms
Option
66
ms
Option
33
ms
Make Period
Default
ch
t M/
ca
Option
t /B
dBr
Option
33
ms
Option
16.5
ms
35
ms
Pre-Digit Pause
t IDP
Inter-Digit Pause
Te
t PDP
Revision 2.1
38
800
40.8
42
880
ms
ms
Page 21 of 27
austriamicrosystems
Datasheet AS2525
Tone Ringer
Symbol
Parameter
Conditions
Min.
Typ.
Max.
Units
F1
Frequency 1
770
800
830
Hz
F2
Frequency 2
1025
1067
1110
Hz
F3
Frequency 3
1280
1333
1385
Hz
t DT
Detection Time
f MIN
Min. Detection Frequency
12
13
f MAX
Max. Detection Frequency
68
70
Pacifier Tone
Symbol
Tone Output Level, RO
Conditions
RL = 150
Min.
14
Hz
75
Hz
Typ.
Max.
30
am
lc s
on A
te G
nt
st
il
V PARO
Parameter
ms
al
id
100
lv
Initial
Units
mV P-P
Tone Output Level, LO1/2
RL = 32
300
mV P-P
f PT
Frequency
Key entry
1333
Hz
t TBD
Tone Burst Duration
Key entry
40
ms
Acknowledge, terminate PG
mode
140
ms
4x40
ms
80
ms
Rejection, invalid key entry
Inter-Tone Pause
Te
ch
ni
ca
t ITP
Revision 2.1
Page 22 of 27
austriamicrosystems
Datasheet AS2525
Timing Diagrams
LD dialling
MUTE
MASK
tIDP
tPDP
tB
tM
tB
tM
tIDP
DPN
tIDP
MF dialling
MUTE
MASK
DPN
TONE
tPDP
tITP
tB
tTD
tM
tITP
tB
tAP
tM
Pause
tAP
Pause
tIDP
tTD
tPDP
tB
tM
tITP
Figure 9: Timing diagrams
Te
ch
ni
ca
tTD
tM
am
lc s
on A
te G
nt
st
il
MUTE
MASK
tB
lv
LD dialling with access pause
tPDP
al
id
DPN
Revision 2.1
Page 23 of 27
austriamicrosystems
Datasheet AS2525
Test Circuit
A
CM
CI
17
LS
10 µ
100 µ
15
30 ohm
RI
ILINE
M1
M2
18
15 n
10
15 n
8
600 ohm
11
6k
M3
15 n
9
1µ
10 V
M4
B
14
AGND
23
am
lc s
on A
te G
nt
st
il
LI
15 n
7
1k
lv
300 ohm
UL
STB
1k
al
id
25
12
BC
327
13
16
BC
327
26
10 µ
CS
Vss
OSC
33
3.58 MHz
SS
VPP
LO1
LO2
27
32 ohm
28
22 µ
29
VsSA
RO
CS1
RECI
44
43
42
41
19
DO
DI
ca
ni
ch
Te
CS2
3
4
32
30
31
37
38
39
40
RECV
20
CLK
1
2
21
FT1
HS
FT2
CBN
150 ohm
100 n
100 n
10 µ
DPn
HF
10 µ
10 k
10 k
5
6
10 µ
24
10 µ
LED
DM/HM
VDD
22
22 µ
FCI
C1
34
C2
R1
C3
R2
C4
R3
35
36
Figure 10: Test circuit
Revision 2.1
Page 24 of 27
austriamicrosystems
Datasheet AS2525
Te
ch
ni
ca
am
lc s
on A
te G
nt
st
il
lv
al
id
Typical Application
Figure 11: Typical application
Revision 2.1
Page 25 of 27
austriamicrosystems
Datasheet AS2525
Packaging
Ordering Information
Number
Package
Description
AS2525 Q
TQFP
plastic thin quad flat package –
44 leads (suffix T)
Marking, Pin-out
AS2525 F
DOF
Dice-on-Foil
39
1
28
am
lc s
on A
te G
nt
st
il
6
YYWWAAA
AS2525x
Austria
CS
VSS
LI
RI
SS
LS
CI
RECI
RECV
RO
VDD
17
year of production
calendar week of production
austriamicrosystems AG assembly ID
X
revision
Te
ch
ni
ca
YY
WW
AAA
Revision 2.1
OSC
LED
FCI
DM/HM
VSSA
LO2
LO1
VPP
CM
CBN
AGND
al
id
CS2
DPn
HF
HS
FT1
FT2
M4
M2
M3
M1
STB
Devices sold by austriamicrosystems AG are covered by
the warranty and patent identification provisions appearing
in its Term of Sale. austriamicrosystems AG makes no
warranty, express, statutory, implied, or by description
regarding the information set forth herein or regarding the
freedom of the described devices from patent infringement.
austriamicrosystems AG 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 austriamicrosystems AG 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 equipment
are specifically not recommended without additional
processing by austriamicrosystems AG for each
application.
lv
CS1
DO
DI
CLK
C4
C3
C2
C1
R3
R2
R1
44-in plastic TQFP (suffix Q)
For exact mechanical package dimensions please see
austriamicrosystems AG packaging information.
Copyright
Copyright © 1997-2002, austriamicrosystems AG, Schloss
Premstaetten, 8141 Unterpremstaetten, Austria-Europe.
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 austriamicrosystems AG
is believed to be correct and accurate. However,
austriamicrosystems AG 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
austriamicrosystems AG rendering of technical or other
services.
Page 26 of 27
austriamicrosystems
Datasheet AS2525
Contact
Headquarters
al
id
austriamicrosystems AG
Communications Business Unit
A 8141 Schloss Premstätten, Austria
T. +43 (0) 3136 500 0
F. +43 (0) 3136 525 01
www.austriamicrosystems.com
USA (east)
Germany
austriamicrosystems USA, Inc.
Suite 400, 8601 Six Forks Road
Raleigh, NC 27615, USA
Phone: +1/919/676 5292
Fax: +1/919/676 5305
am
lc s
on A
te G
nt
st
il
austriamicrosystems Germany GmbH
Tegernseer Landstrasse 85
D-81539 München, Germany
Phone: +49/89/693643-0
Fax: +49/89/693643-66
lv
Sales Offices
United Kingdom
France
austriamicrosystems France S.a.r.l.
124, Avenue de Paris
F-94300 Vincennes, France
Phone: +33/1/43 74 00 90
Fax: +33/1/43 74 20 98
austriamicrosystems UK, Ltd.
Coliseum Business Centre, Watchmoor Park
Camberley, Surrey, GU15 3YL, UK
Phone: +44/1276/23 3 99
Fax: +44/1276/29 3 53
Japan
Italy
Switzerland
ca
austriamicrosystems Italy S.r.l.
Via Leone Tolstoi, 64
I-20146 Milano, Italy
Phone: +39/0242/36713
Fax: +39/0242/290889
austriamicrosystems AG
Shin Yokohama Daini, Center Bldg. 10F
3-19-5, Shin Yokohama
Kohoku-ku, Yokohama 222-0033, Japan
Phone: +81/45/474 0962
Fax: +81/45/472 9845
Distributors & Representatives
USA (west)
Spain, Israel, Korea, Hong-Kong, Taiwan, Malaysia,
Singapore, India, Brazil
Te
ch
ni
austriamicrosystems Switzerland AG
Rietstrasse 4
CH-8640 Rapperswil, Switzerland
Phone: +41/55/220 9000
Fax: +41/55/220 9001
austriamicrosystems USA, Inc.
Suite 116, 4030 Moorpark Ave,
San Jose, CA 95117, USA
Phone: +1/408/345 1790
Fax: +1/408/345 1795
Revision 2.1
austriamicrosystems AG is represented by distributors in
the following countries. Please contact your nearest
regional sales office for the distributor address:
Application Support
Please contact your local sales office or your distributor.
Page 27 of 27