AMSCO AS2590N

Data Sheet
AS2590

LC DISPLAY DRIVER WITH 18 DIGITS,
6 SYMBOLS AND CLOCK/TIMER
Austria Mikro Systeme International
Key Features
General Description
❑ Very low operating current, typ. 30 µA @ 3V
❑ Low power oscillator using 32.768 kHz Xtal
The AS2590 is an integrated CMOS device for driving a
liquid crystal display intended for use in telephones. The
❑ 2-wire interface compatible to AS2574B
❑ 18 digits by 7 segments
2-wire serial interface is compatible to the dialler
AS2574B.
❑ 6 symbols
❑ 24 hour clock showing hours and minutes
The extreme low operating current allows the circuit to
❑ Timer automatically showing elapsed time in
minutes and seconds after each telephone
be operational also during on-hook which is necessary
in order to the use of the clock function. In on-hook
conversation
❑ 33 LCD segment outputs and 4 LCD backplane
condition the circuit can be supplied by a small leakage
current from the telephone line or from a small 3V
outputs
❑ 4 times multiplex mode with a cycle time of 128 Hz
battery.
❑ Mode select pin for selecting clock function
Whether the oscillator shall continue operating or be
stopped during on-hook is determined by the mode pin,
MS.
Package
Available in 48 pin DIP and 52 pin PLCC.
SPEECH CIRCUIT
VDD
VDD
V13
AS2574A/B
VLCD
SDA
32.768kHz
X1
X2
BIAS
SCL
Vss
Rev. 1
AS2590
DIALLER
CONTROLLER
KEYBOARD
MS
V23
Vss
1
Dec. 1993
Data Sheet
AS2590
Pin Description
DIL
PLCC
Symbol
1
2
1
2
BP1
BP0
3
4
5
6
7
8
9
10
11
12
3
4
5
6
8
9
10
11
12
13
S0
S1
S2
S3
S4
S5
S6
S7
S8
S9
13
14
V1/3
1/3 of VDD pin for external voltage divider
14
15
16
17
18
19
20
21
22
23
15
16
17
18
19
21
22
23
24
25
S10
S11
S12
S13
S14
S15
S16
S17
S18
S19
Segment outputs
24
26
VSS
Negative supply pin
25
26
27
28
BP3
BP2
Back plane outputs
27
29
V2/3
2/3 of VDD pin for external voltage divider
28
29
30
31
32
33
34
35
36
37
38
39
40
30
31
32
34
35
36
37
38
39
40
41
42
43
S32
S31
S30
S29
S28
S27
S26
S25
S24
S23
S22
S21
S20
Segment outputs
41
44
VLCD
Negative supply pin for LC display
Rev. 1
Function
Blackplanes
Segment outputs
2
Dec. 1993
Data Sheet
AS2590
Pin Description Continued
DIL
PLCC
Symbol
42
43
45
47
SDA
SCL
Serial data line input to dialler/controller
Clock line input of serial data link
44
48
VBIAS
Oscillator bias input, recommended bias resistor 2.2 MΩ
45
46
49
50
XTAL1
XTAL2
47
51
MS
Mode select input:
48
52
VDD
Positive supply pin
LCD Layout
SB3
Function
Oscillator pins for 32.768 kHz crystal, a resistor and two capacitors
SB1
D D D D D D
0 1 2 3 4 5
SB0
MS = VSS › clock/timer disabled
MS = VDD › clock/timer enabled
SB2
SB4
SB5
D D D D D D D D D D D D
6 7 8 9 10 11 12 13 14 15 16 17
Figure 1
SB0 = loudspeaker on (blinking with 1 Hz)
Table 1 Segments Digits
Digit Description
SB1 = microphone muted (blinking with 1 Hz)
0
1
2
3
4
5
6
7
8
9
a
b
c
d
_
*
#
P/T
r
SB2 = 2nd key function enabled
SB3 = number stored
SB4 = number buffered in FIFO, not stored
SB5 = colon for clock and timer (blinking when clock is
shown)
A
F
G
E
B
C
D
Figure 2
Rev. 1
3
numbers
0…9
letter A
letter B
letter C
Letter D
underscore
asterisk
hash
pause
temp. MF
recall
Segment
C D E
on on on
on
on on
on on
on
on on
on on on
on
on on on
on
on on on
on on on
on on
on on on on
on
on on
on
on
on on on
A B
on on
on
on on
on on
on
on
on
on on
on on
on on
on
on
on
F
on
G
on
on
on on
on on
on on
on on
on on
on
on on
on
on
on
on
on
on
on
Dec. 1993
Data Sheet
AS2590
Description
- Power up; enables subsequent start timer commands.
Operating Modes
The following two operating modes are pin selectable:
- BLANK ALL; clears the whole display (including special
symbols) and displays the timer contents for 6 seconds
(if clock/timer function is enabled) or until a new
START TIMER/FIFO command is received. Then it
returns to normal display mode.
Mode 0:
Clock and timer are disabled and the oscillator is stopped
when going on-hook (command BLANK ALL).
- if any command or data is received by the serial
interface within the time out period after a BLANK ALL
command, the timer display will be blanked or replaced
by the clock display.
Mode 1:
Clock and timer functions are enabled, clock is displayed
both during off- and on-hook (assuming that clock is set).
When going from off-hook to on-hook, the timer content
(elepsed time) is displayed for 6 seconds (assuming that
a start timer command was received).
The timer is displayed in the format mm:ss with the
leading zero of the minutes suppressed and symbol 5 (:)
turned on.
Clock
After a power up reset the clock is disabled. The clock
will not be displayed until a valid set clock procedure has
been performed (mode 1 only). The format of the clock
is hh:mm and the leading zero of the hours is suppressed
and symbol 5 (:) is blinking with a frequency of 1 Hz. The
timer is running when off-hook and displayed for 6
seconds when going on-hook. The content of the timer
(elapsed time) is shown in stead of the clock in the format
mm:ss.
LCD Outputs
The 33 segment outputs and 4 backplane outputs can
drive a customized liquid crystal display in 1:4 multiplex
mode. Two reference voltages V1/3 and V2/3 are
provided by an external voltage divider.
Digits and Special Symbols
The display consists of 18 seven segment digits and 6
special symbols (see figure 1):
- D0…D17; D0 is the most left seven segment digit, the
possible numbers displayed by one digit are shown in
figure 2. The symbol (_) is only displayed at D13, D14,
D16 and D17 when setting the clock.
If a SET CLOCK command is received the display is
blanked, four underscore symbols are displayed where
the 4 digits of the clock will be entered (the 4 most right
digits) and symbol 5 is turned on (_ _ : _ _). The next 4
data words are interpreted as the time (hh mm). The
fourth digit terminates the SET CLOCK and starts the
clock with the seconds set to zero.
- SB0…SB5; 6 special symbols (one segment for each
symbol only), see figure 1 for reference. If SB0
(loudspeaker on) or SB1 (microphone muted) are
turned on, they blink with a frequency of 1 Hz.
If less than 4 data words (digits) are received the first
command (normally a BLANK DIGITS or a BLANK ALL)
will terminate the SET CLOCK. But as the procedure
was incomplete, it is regarded as invalid and further
clock display is disabled. The next valid SET CLOCK
command will enable the clock again. The SET CLOCK
command does not effect the timer.
Multiplex Mode
A total of 132 segments are addressable. One output
drives 4 segments in a time multiplex mode. The 4
backplane outputs determine the currently addressed
segment (see figure 3).
Figure 3 gives the correlation between segment outputs
and addressed segments.
The time-out condition (approx. 15 seconds) when setting
clock is recognized by the dialler/controller (e.g. AS2574).
If a time-out condition occours the dialler sends a
BLANK ALL command to terminated the SET CLOCK.
Data and Commands
32 different words may be received via the serial interface.
19 words are interpreted as display data for one of the
18 seven segment digits. Table 2 gives the translation
from received code to displayed symbol.
Timer
The following commands effect the timer:
- START TIMER and START FIFO; they start the timer.
If the timer is already running, it cannot be restarted
by one of these commands before stopping the timer
with the BLANK ALL command.
Rev. 1
13 words are valid commands codes. The function of
each command is described in table 2, and table 4 lists
the 5 bit codes for all possible commands.
4
Dec. 1993
Data Sheet
AS2590
Table 2 Command Summary
NO
MNEMONIC
FUNCTION
1
2
SET LS
CLEAR LS
Turns on special symbol SB0 (loudspeaker on, blinking)
Turns off special symbol SB0
3
4
SET MUTE
CLEAR MUTE
Turns on special symbol SB1 (microphone muted, blinking)
Turns off special symbol SB1
5
6
SET 2ND
CLEAR 2ND
Turns on special symbol SB2 (2nd function on keyboard)
Turns off special symbol SB2
7
8
SET CLOCK
START
Initiates clock setting; SB5 is turned on
Blanks all digits, SB3 and SB4; accepts data, timer not started
9
START COPY
Blanks all digits and SB4; turns on SB3, accepts data, timer not started (if not
already running)
10
START FIFO
Blanks all digits and SB3; turns on SB4, accepts data, timer started (if not
already running)
11
START TIMER
Blanks all digits, turns off SB3 and SB4, accepts data, timer started (if not
already running)
12
BLANK ALL
Blanks all digits and all special symbols (except D13, D14, D16, D17 and SB5
when clock is running)
13
TEST MODE
Turns circuit into test mode
Table 3 Segment Mapping
SEGMENT
OUTPUT
S0
S1
BP0
SB0
D0/F
BACKPLANE
BP1
BP2
SB1
SB4
D0/G
D0/E
BP3
SB2
D0/D
SEGMENT
OUTPUT
S17
S18
BP0
D9/F
D9/A
BACKPLANE
BP1
BP2
D9/G
D9/E
D9/B
D10/G
BP3
D9/C
D10/E
S2
S3
D0/A
D1/F
D0/B
D1/G
D0/C
D1/E
D1/D
D1/C
S19
S20
D10/A
D11/A
D10/F
D11/F
D10/B
D11/E
D10/C
D10/D
S4
S5
D1/A
D2/A
D1/B
D2/F
D2/G
D2/B
D2/E
D2/C
S21
S22
D11/B
D12/F
D11/G
D12/G
D11/C
D12/E
D11/D
D12/D
S6
S7
D3/A
D3/B
D3/F
D3/G
D2/E
D3/C
D2/D
D3/D
S23
S24
D12/A
D13/F
D12/B
D13/G
D12/C
D13/E
D13/D
D13/C
S8
S9
D4/F
D4/A
D4/G
D4/B
D4/E
D4/C
D4/D
D5/D
S25
S26
D13/A
D14/A
D13/B
D14/F
D14/G
D14/B
D14/E
D14/C
S10
S11
D5/F
D5/A
D5/G
D5/B
D5/E
D6/G
D5/C
D6/E
S27
S28
D15/A
D15/B
D15/F
D15/G
D15/E
SB5
D14/D
D15/D
S12
S13
D6/A
D7/A
D6/F
D7/F
D6/B
D7/E
D6/C
D6/D
S29
S30
D16/F
D16/A
D16/G
D16/B
D16/E
D16/C
D16/D
D17/D
S14
S15
D7/B
D8/F
D7/G
D8/G
D7/C
D8/E
D7/D
D8/D
S31
S32
D17/F
D17/A
D17/G
D17/B
D17/E
D15/C
D17/C
SB3
S16
D8/A
D8/B
D8/C
D9/D
Dn/m = segment m of digit n
SBn = special symbol n
Rev. 1
5
Dec. 1993
Data Sheet
BP0
AS2590
to high transition of the data line while the clock line is
high followed by a negative clock pulse indicates a stop
condition (see figure 4).
Active Backplane
BP1
BP2
BP3
VDD
V2/3
V1/3
Vss
BP0
Table 4 Codes for Serial Interface
VDD
V2/3
V1/3
Vss
BP1
NO SYMBOL MSB
1 SB0-on
0
2 SB0-off
0
VDD
V2/3
V1/3
Vss
BP2
VDD
V2/3
V1/3
Vss
BP3
off
VDD
V2/3
V1/3
Vss
on
VDD
V2/3
V1/3
Vss
S0
on
off
off
S1
off
on
on
Figure 3 LCD driver outputs
Serial Interface
The serial interface is a one way, two line link between
the dialler (AS2574) and the display driver. The two lines
are the serial data line (SDA) and the serial clock line
(SCL). The display driver can only receive data.
Word Transfer:
Data are transferred as 5 bit words with start and stop bit.
the least significant bit is sent first after the start bit. As
long as there is no data transfer, both data and clock
lines have to remain high. Also between two words both
lines have to stay high for a specified time. Figure 4
shows the timing of the serial interface.
Start and Stop Conditions:
A start condition is detected when the data line goes
from high to low while the clock line is held high. A low
B3
0
0
B2
1
0
B1
0
1
LSB HEX
1
05
1
03
3
4
SB1-on
SB1-off
1
0
0
1
0
0
0
0
1
1
11
09
5
6
SB2-on
SB2-off
0
1
0
1
1
1
1
1
1
1
07
1F
7
8
SET CLOCK
START
0
0
1
1
0
1
1
0
1
1
0B
0D
9
10
COPY
FIFO
0
1
1
0
1
0
1
1
1
1
0F
13
11
12
TIMER
BLANK
1
1
0
1
1
1
0
0
1
1
15
1D
13
14
TEST
0
1
1
0
1
1
1
1
0
1
0
17
1C
15
16
1
2
0
0
0
0
0
1
0
0
0
0
00
04
17
18
3
4
0
1
0
0
0
0
1
0
0
0
02
10
19
20
5
6
1
1
0
0
1
0
0
1
0
0
14
12
21
22
7
8
0
0
1
1
0
1
0
0
0
0
08
0C
23
24
9
a
0
0
1
0
0
1
1
1
0
0
0A
06
25
26
b
c
1
0
0
1
1
1
1
1
0
0
16
0E
27
28
d
*
1
1
1
1
1
0
1
0
0
0
1E
18
29
30
#
–
1
1
1
1
0
0
1
1
0
1
1A
1B
31
32
P/T
r
1
0
1
0
0
0
0
0
1
1
19
01
SDA
SCL
START
#1
LSB
B0
B1
B2
B3
MSB
B4
STOP
#1
WORD START
GAP
#2
Figure 4 Interface Timing
Rev. 1
6
Dec. 1993
Data Sheet
AS2590
Electrical Characteristics
Absolute Maximum Ratings
Positive Supply Voltage ...................................................................................................................-0.3V ≤ VDD ≤ 7V
Input Current ................................................................................................................................................± 25 mA
Digital Input Voltage .....................................................................................................VSS - 0.3V ≤ VIN ≤ VDD + 0.3V
Electrostatic Discharge (HBM) ........................................................................................................................±500V
Storage Temperature ......................................................................................................................-65°C to +125°C
Recommended Operating Conditions
Supply Voltage ..............................................................................................................................2.5V ≤ VDD ≤ 5.5V
Oscillator Frequency ...............................................................................................................................32.768 kHz
Operating Temperature ....................................................................................................................- 25°C to +70°C
DC Characteristics (Default conditions: recommended operating conditions; outputs unloaded; VDD = 3.0V)
Symbol
Parameter
Conditions
Min
Typ
Max
Units
1.5
µA
50
µA
Test circuit fig. 5
IDD0
Standby Current
no clock running
IDD
Operating Current
TAMB = 5 to 55 °C
30
Note 1, note 2
VIL
Input Voltage, Low
VSS
0.2 VDD
V
VIH
Line Voltage, High
0.8 VDD
VDD
V
VLCD
Output Voltage, Sink
0.4
V
RBIAS
Oscillator Bias Resistor
ILCD = 4.8 mA
2.2
MΩ
Note 1: Segment and backplane outputs loaded with maximum 30 pF, power consumption of external voltage divider not
included, RBIAS = 2.2 MΩ ± 10%.
Note 2: Xtal parameters:
Rev. 1
Rimax = 60 kΩ (Rityp = 30 kΩ)
Qmin = 35 000
Co = 1.5 pF (capacitance across Xtal terminals)
fxtal = 32.768 kHz
7
Dec. 1993
Data Sheet
AS2590
AC Characteristics (VDD = 3.0V; TAMB = -25 to 70 °C, unless otherwise specified)
Symbol
Parameter
Conditions
Min
Typ
SDA/SCL
Serial Interface
Fig. 5
fCL
Clock Frequency
10
kHz
fCLH
Clock High Time
50
µs
fCLL
Clock Low Time
50
µs
fCD
Clock Low to Data Change
fSOH
Stop Bit High Time
50
µs
fSOL
Stop Bit Low Time
50
µs
fHD
Data Hold Time
200
ns
fSUSO
Clock Setup for Stop
200
ns
fHSA
Clock Hold for Start
200
ns
fGAP
Data High between 2 Words
BP0…3
Back Plane Outputs
tBRON
Rise Time, on
20
µs
tBFON
Fall Time, on
20
µs
tBROF
Rise Time, off
20
µs
tBFOF
Fall Time, off
20
µs
tBC
Cycle Frequency
S0…32
Segment Outputs
tSRON
Rise Time, on
20
µs
tSFON
Fall Time, on
20
µs
tSROF
Rise Time, off
20
µs
tSFOF
Fall Time, off
20
µs
tSC
Cycle Frequency
tTIMER
Timer Display Time
Note 3
tXUP
Oscillator Startup Time
RBIAS = 2.2 MΩ
20
Max
Units
tCLL
ns
µs
100
Figure 6, note 1
128
Hz
Figure 7, note 2
128
5
Hz
6
sec
300
ms
Note 1: Loads on backplanes = 3 000 pF//10 MΩ
Note 2: Loads on segments = 360 pF//1 MΩ
Note 3: After BLANK ALL command and timer has been started with a valid start command, timer content is displayed.
Rev. 1
8
Dec. 1993
Data Sheet
AS2590
Timing Diagrammes
tHSA
tCD
tHD
SDA
tCLH
tCLL
SCL
START
BIT 1
BIT 0
tSUSO
tSOH
…
tGAP
SDA
tCLL
tSOL
SCL
BIT 4
STOP
WORD GAP…
Figure 5 Serial Interface timing waveforms
Rev. 1
9
Dec. 1993
Data Sheet
AS2590
Output Waveforms
tBC
tBRON
tBC
tBFON
VDD
0.9 VDD
tBROF
tBROF
0.1 VDD
Vss
Figure 6 Backplane timing waveforms
tSC
tSFON
tSRON
tSC
VDD
0.9 VDD
tSFOF
tSFOF
0.1 VDD
Vss
Figure 7 Segment timing waveforms
Rev. 1
10
Dec. 1993
Data Sheet
AS2590
Pin Configurations
48 Pin DIP
48
VDD
BP0
2
47
MS
S0
3
46
XTAL2
S1
4
45
XTAL1
S2
5
44
VBIAS
S3
6
43
S4
7
42
SCL
SDA
S5
8
41
VLCD
S6
S7
9
40
39
S20
S21
S8
11
38
S22
S9
37
S23
V1/3
12
13
36
S24
S10
14
35
S25
S11
15
34
S26
S12
16
33
S27
S13
17
32
S28
S14
18
31
S29
S15
19
30
S30
S16
20
29
S31
S17
21
28
S32
S18
22
27
V2/3
S19
23
26
BP2
Vss
24
25
BP3
Rev. 1
10
S4
S5
S6
S7
S8
S9
V1/3
S10
S11
S12
S13
S14
NC
1
14
AS2590
40
27
NC
SDA
VLCD
S20
S21
S22
S23
S24
S25
S26
S27
S28
S29
S15
S16
S17
S18
S19
VSS
BP3
BP2
V2/3
S32
S31
S30
NC
1
AS2590
BP1
NC
S3
S2
S1
S0
BP0
BP1
VDD
MS
XTAL2
XTAL1
VBIAS
SCL
52 pin PLCC
Ordering Information:
48 pin DIP:
52 pin PLCC:
AS2590 P
AS2590 N
Applications:
For application support contact your local AMS sales
offices.
11
Dec. 1993
Data Sheet
AS2590
Sales Representative
Devices sold by Austria Mikro Systeme are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. Austria Mikro Systeme 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. 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 equipment are specifically not recommended without additional processing by Austria Mikro Systeme for each application.
Copyright  1993, 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 is believed to be correct and accurate. However, Austria Mikro Systeme 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 rendering
of technical or other services.
Rev. 1
12
Dec. 1993