AS1110
D a ta S he e t
C o n s tan t - C u r r e n t , 1 6 - C h a n n e l L ED Driver with Diagnost ics
1 General Description
2 Key Features
!
The AS1110 is designed to drive up to 16 LEDs through
a fast serial interface and features 16 output constant
current drivers and an on-chip diagnostic read-back
function.
!
16 Constant-Current Output Channels
Excellent Output Current Accuracy
- Between Channels: <±3%
- Between Devices: <±6%
The high clock-frequency (up to 50MHz), adjustable output current, and flexible serial interface makes the
device perfectly suited for high-volume transmission
applications.
!
Output Current Per Channel: 0.5 to 100mA
!
Controlled In-Rush Current
Output current is adjustable (up to 100mA/channel)
using an external resistor (REXT).
!
Over-Temperature, Open-LED, Shorted-LED
Diagnostic Functions
The serial interface with Schmitt trigger inputs includes
an integrated shift register. Additionally, an internal data
register stores the currently displayed data.
!
Low-Current Test Mode
!
Global Fault Monitoring
The device features integrated diagnostics for overtemperature, open-LED, and shorted-LED conditions.
Integrated registers store global fault status information
during load as well as the detailed temperature/openLED/shorted-LED diagnostics results.
!
Low Shutdown Mode Current: 10µA
!
Fast Serial Interface: 50MHz
!
Cascaded Configuration
!
Extremely Fast Output Drivers Suitable for PWM
!
24-pin SSOP and 28-pin QFN (5x5mm) Package
The AS1110 also features a low-current diagnostic
mode to minimize display flicker during fault testing.
The AS1110 is available in a 24-pin SSOP and the 28pin QFN (5x5mm) package.
3 Applications
AS1110
SDI
CLK
www.austriamicrosystems.com
LD
OEN
REXT
Revision 1.00
OUTN15
OUTN14
OUTN13
OUTN12
OUTN9
OUTN8
OUTN7
OUTN6
OUTN5
OUTN4
OUTN3
OUTN2
OUTN1
OUTN0
+VLED
OUTN11
Figure 1. Main Diagram and Pin Assignments
OUTN10
The device is ideal for fixed- or slow-rolling displays
using static or multiplexed LED matrix and dimming
functions, large LED matrix displays, mixed LED display
and switch monitoring, displays in elevators, public
transports (underground, trains, buses, taxis, airplanes,
etc.), large displays in stadiums and public areas, price
indicators in retail stores, promotional panels, bar-graph
displays, industrial controller displays, white good panels, emergency light indicators, and traffic signs.
SDO
GND
VDD
1 - 24
AS1110
Data Sheet
Contents
1 General Description ................................................................................................................................ 1
2 Key Features .......................................................................................................................................... 1
3 Applications ............................................................................................................................................ 1
4 Pinout ..................................................................................................................................................... 3
Pin Assignments ..................................................................................................................................................... 3
Pin Descriptions ..................................................................................................................................................... 3
5 Absolute Maximum Ratings .................................................................................................................... 4
6 Electrical Characteristics ........................................................................................................................ 5
Switching Characteristics ....................................................................................................................................... 6
7 Typical Operating Characteristics ........................................................................................................... 7
8 Detailed Description ............................................................................................................................... 8
Serial Interface ....................................................................................................................................................... 9
Timing Diagrams .................................................................................................................................................... 9
Error-Detection Mode ........................................................................................................................................... 11
Global Error Mode ................................................................................................................................................ 11
Error Detection Functions ..................................................................................................................................... 12
Open-LED Detection ..................................................................................................................................... 12
Shorted-LED ................................................................................................................................................. 12
Overtemperature ........................................................................................................................................... 12
Detailed Error Reports .......................................................................................................................................... 13
Detailed Temperature Warning Report .........................................................................................................
Detailed Open-LED Error Report ..................................................................................................................
Detailed Shorted-LED Error Report ..............................................................................................................
Low-Current Diagnostic Mode .......................................................................................................................
13
14
15
15
Shutdown Mode .................................................................................................................................................... 16
9 Application Information ......................................................................................................................... 17
Error Detection ..................................................................................................................................................... 17
Error Detection On-The-Fly ........................................................................................................................... 17
Error Detection with Low-Current Diagnosis Mode ....................................................................................... 17
Cascading Devices ............................................................................................................................................... 18
Constant Current .................................................................................................................................................. 19
Adjusting Output Current ...................................................................................................................................... 19
Package Power Dissipation .................................................................................................................................. 19
Delayed Outputs ................................................................................................................................................... 19
Switching-Noise Reduction .................................................................................................................................. 19
Load Supply Voltage ............................................................................................................................................. 19
10 Package Drawings and Markings ....................................................................................................... 21
11 Ordering Information ........................................................................................................................... 23
www.austriamicrosystems.com
Revision 1.00
2 - 24
AS1110
Data Sheet - P i n o u t
4 Pinout
Pin Assignments
OUTN8
OUTN9
OUTN10
OUTN11
OUTN12
OUTN13
OUTN14
OUTN15
OEN
SDO
CLK
1
21 SDO
VDD
28 27 26 25 24 23 22
REXT
VDD
REXT
GND
GND
GND
SDI
GND
Figure 2. Pin Assignments (Top View)
LD
2
20 OEN
24 23 22 21 20 19 18 17 16 15 14 13
OUTN0
3
AS1110
19 OUTN15
OUTN1
4
28-pin QFN 5x5
18 OUTN14
OUTN2
5
17 OUTN13
OUTN3
6
16 OUTN12
OUTN4
7
15 OUTN11
AS1110
4
5
6
7
8
9 10 11 12
SDI
CLK
LD
OUTN0
OUTN1
OUTN2
OUTN3
OUTN4
OUTN7
3
OUTN6
2
OUTN5
1
GND
OUTN9
OUTN10
OUTN8
OUTN6
10 11 12 13 14
N/C
9
OUTN7
8
OUTN5
24-pin SSOP
Pin Descriptions
Table 1. Pin Descriptions
Pin Number
SSOP
QFN
Pin Name
Description
1
24:27
GND
Ground
2
28
SDI
Serial Data Input
3
1
CLK
Serial Data Clock. The rising edge of the CLK signal is used to clock data
into and out of the AS1110 shift register. In error mode, the rising edge of the
CLK signal is used to switch error modes.
4
2
LD
5:20
3:10
12:19
OUTN0:15
Output Current Drivers. These pins are used as LED drivers or for input
sense for diagnostic modes. Data is transferred to the data register at the
rising edge of these pins.
OEN
Output Enable. The active-low pin OEN signal can always enable output
drivers to sink current independent of the AS1110 mode.
0 = Output drivers are enabled.
1 = Output drivers are disabled.
21
20
Serial Data Load
22
21
SDO
Serial Data Output. In normal mode SDO is latched out 8.5 clock cycles
after SDI is latched in.
In global error detection mode this pin indicates the occurrence of a global
error.
0 = Global error mode returned an error.
1 = No errors.
23
22
REXT
External Resistor Connection. This pin connects through the external
resistor (REXT) to GND, to setup the load current.
24
23
VDD
Positive Supply Voltage
-
11
N/C
Not connected
www.austriamicrosystems.com
Revision 1.00
3 - 24
AS1110
Data Sheet - A b s o l u t e M a x i m u m R a t i n g s
5 Absolute Maximum Ratings
Stresses beyond those listed in Table 2 may cause permanent damage to the device. These are stress ratings only,
and functional operation of the device at these or any other conditions beyond those indicated in Section 6 Electrical
Characteristics on page 5 is not implied. Exposure to absolute maximum rating conditions for extended periods may
affect device reliability.
Table 2. Absolute Maximum Ratings
Parameter
Min
Max
Units
VDD to GND
0
7
V
Input Voltage
-0.4
VDD
+0.4
V
Output Voltage
-0.4
GND Pin Current
Thermal Resistance ΘJA
15
V
2000
mA
24-pin SSOP package
2800
mA
28-pin QFN (5x5mm) package
88
ºC/W
on PCB, 24-pin SSOP package
on PCB, 28-pin QFN (5x5mm) package
23
ºC/W
Ambient Temperature
-40
+85
ºC
Storage Temperature
-55
150
ºC
Humidity
5
86
%
Electrostatic
Discharge
Digital Outputs
2000
All Other Pins
2000
Latch-Up Immunity
Package Body Temperature
www.austriamicrosystems.com
Comments
+100 +
-100 (INOM x 0.5) INOM
+260
V
Non-condensing
Norm: MIL 833 E method 3015
mA
EIA/JESD78
ºC
The reflow peak soldering temperature (body
temperature) specified is in accordance with
IPC/JEDEC J-STD-020C “Moisture/Reflow
Sensitivity Classification for Non-Hermetic Solid
State Surface Mount Devices”.
The lead finish for Pb-free leaded packages is
matte tin (100% Sn).
Revision 1.00
4 - 24
AS1110
Data Sheet - E l e c t r i c a l C h a r a c t e r i s t i c s
6 Electrical Characteristics
VDD = +3.0 to +5.5V, TAMB = -40 to +85ºC (unless otherwise specified).
Table 3. Electrical Characteristics
Symbol
Parameter
VDD
Supply Voltage
VDS
Output Voltage
IOUT
IOH
Condition
Max
Unit
3.0
5.5
V
OUTN0:15
0
15.0
V
OUTN0:15
0.5
100
Output Current
IOL
VIH
Input Voltage
IDS(OFF)
VOL
VOH
-1.0
SDO
1.0
CLK, OEN, LD, SDI
Low Level
Output Leakage Current
Output
Voltage
Typ
SDO
High Level
VIL
Min
0.7 x
VDD
VDD +
0.3
-0.3
0.3 x
VDD
OEN = 1, VDS = 15.0V
0.5
IOL = +1.0mA
SDO
IOH = -1.0mA
24.5
Device-to-Device Average Output
Current from OUTN0 to OUTN15
VDS = 0.5V, VDD = Const.,
REXT = 744Ω
ΔIAV(LC1)
Current Skew
(Between Channels)
IOUT = 25.26mA, VDS ≥ 0.5V,
VDD = Const., REXT = 744Ω
IAV(LC2)
Device-to-Device Average Output
Current from OUTN0 to OUTN15
VDS = 0.6V, VDD > 3.3V,
REXT = 372Ω
ΔIAV(LC2)
Current Skew
(Between Channels)
IOUT = 50.52mA, VDS ≥ 0.6V,
VDD = Const., REXT = 372Ω
IAV(LC3)
Device-to-Device Average Output
Current from OUTN0 to OUTN15
VDS = 0.8V, VDD = 5.0V,
REXT = 186Ω
ΔIAV(LC3)
Current Skew
(Between Channels)
IOUT = 90mA, VDS ≥ 0.8V,
VDD = Const., REXT = 186Ω
ILC
Low-Current Diagnosis Mode
VDS = 0.8V, VDD = 5.0V
IPD
Power Down Supply Current
%/ΔVDS
%/ΔVDD
V
µA
0.4
VDD 0.4V
IAV(LC1)
mA
V
26
mA
±3
%
51.55
mA
±2
%
104
mA
±1
±2
%
0.6
0.8
mA
VDS = 0.8V, VDD = 5.0V,
REXT = 372Ω, OUTN0:15 = On
10
20
µA
Output Current vs.
Output Voltage Regulation
VDS within 1.0 and 3.0V
±0.1
%/V
Output Current vs.
Supply Voltage Regulation
VDD within 3.0 and 5.0V
±1
%/V
±1
49.50
±1
98
0.4
RIN(UP)
Pullup Resistance
OEN
250
500
800
kΩ
RIN(DOWN)
Pulldown Resistance
LD
250
500
800
kΩ
VTHL
Error Detection Threshold Voltage
0.25
0.3
0.45
V
VTHH
Error Detection Threshold Voltage
VDD = 3.0V
1.2
1.3
1.4
VDD = 5.0V
2.0
2.2
2.4
TOV1
Overtemperature Threshold Flag
www.austriamicrosystems.com
150
Revision 1.00
V
ºC
5 - 24
AS1110
Data Sheet - E l e c t r i c a l C h a r a c t e r i s t i c s
Table 3. Electrical Characteristics (Continued)
Symbol
Parameter
Condition
IDD(OFF)0
IDD(OFF)1
Off
IDD(OFF)2
IDD(OFF)3
Supply
Current
IDD(ON)1
IDD(ON)2
On
IDD(ON)3
Min
Typ
Max
REXT = Open‚ OUTN0:15 = Off
2.7
6
REXT = 744Ω‚ OUTN0:15 = Off
4.3
8
REXT = 372Ω‚ OUTN0:15 = Off
5.4
9
REXT = 186Ω, OUTN0:15 = Off
9.3
13
REXT = 744Ω‚ OUTN0:15 = On
6.2
11
REXT = 372Ω‚ OUTN0:15 = On
10.5
15
REXT = 186Ω‚ OUTN0:15 = On
19.5
26
Unit
mA
Switching Characteristics
VDD = 3.0 to 5.5V, VDS = 0.8V, VIH = VDD, VIL = GND, REXT = 372Ω, VLOAD = 4.0V, RLOAD = 64Ω, CLOAD = 10pF; guaranteed by design.
Table 4. Switching Characteristics for VDD = 5V
Symbol
tP1
tP2
tP3
tP4
tW(CLK)
tW(L)
tW(OE)
tR
Parameter
Propagation Delay Time (Without
Staggered Output Delay)
Conditions
CLK - SDO
LD - OUTNn
OEN - OUTNn
Min
CLK
LD
OEN (@IOUT < 60mA)
15
15
200
Typ
5
100
100
Propagation Delay Time
Pulse Width
Max
10
200
200
10
Unit
ns
ns
ns
*
CLK Rise Time
500
ns
*
CLK Fall Time
500
ns
100
100
200
300
20
40
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
tF
tOR
tOF
fCLK
Output Rise Time of VOUT (Turn Off)
Output Fall Time of VOUT (Turn On)
Setup Time for SDI
Hold Time for SDI
Setup Time for LD
Hold Time for LD
OEN Time for Error Detection
Staggered Output Delay
Output Enable Setup Time
Global Error Switching Setup Time
Global Error Detection Setup Time
Propagation Delay Global Error Flag
Switching Time Global Error Flag
Maximum Clock Frequency
(Cascade Operation)
tP3,ON
tP3,OFF
Low-Current Test Mode
Propagation Delay Time
tREXT2,1
External Resistor Reaction Time
tREXT2,1
External Resistor Reaction Time
tSU(D)
tH(D)
tSU(L)
tH(L)
tTESTING
tSTAG
tSU(OE)
tGSW(ERROR)
tSU(ERROR)
tP(I/O)
tSW(ERROR)
5
5
5
5
2000
20
10
10
5
10
30
Turn ON
Turn OFF
Change from REXT1 = 372Ω,
IOUT1 = 50.52mA to REXT2 =
37.2kΩ, IOUT2 < 1mA
Change from REXT1 = 37.2kΩ,
IOUT1 = 0.5mA to REXT2 =
372Ω, IOUT2 > 25mA
50
MHz
3
0.05
5
0.1
µs
µs
0.5
1
µs
0.5
1
µs
*
If multiple AS1110 devices are cascaded and tr or tf is large, it may be critical to achieve the timing required for data
transfer between two cascaded LED drivers.
www.austriamicrosystems.com
Revision 1.00
6 - 24
AS1110
Data Sheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
7 Typical Operating Characteristics
Figure 3. Output Current vs. REXT,
VDD = 5V; VDS = 0.8V, TAMB = 25°C
Figure 4. Relative Output Current Error vs. VDD,
Iout/Iout@VDD=5V - 1, TAMB = 25°C
2
Relative Output Current Error (%)
.
100
IOUT (mA) .
1.5
1
0.5
10
REXT = 744Ω;
VDS = 0.5V
0
-0.5
REXT = 186Ω;
VDS = 0.8V
REXT = 372Ω;
VDS = 0.6V
-1
-1.5
1
100
1000
-2
3
10000
3.5
4
REXT (Ω)
Figure 5. Output Current vs. VDS;
VDD = 5V, TAMB = 25°C
5
5.5
Figure 6. Output Current vs. VDS;
VDD = 5V, TAMB = 25°C
120
120
100
100
REXT = 186Ω
80
IOUT (mA) .
IOUT (mA) .
4.5
VDD (V)
REXT = 251Ω
60
REXT = 372Ω
40
20
REXT = 186Ω
80
REXT = 251Ω
60
REXT = 372Ω
40
20
REXT = 744Ω
0
REXT = 744Ω
0
0
3
6
9
12
15
0
VDS (V)
www.austriamicrosystems.com
0.2
0.4
0.6
0.8
1
1.2
1.4
VDS (V)
Revision 1.00
7 - 24
AS1110
Data Sheet - D e t a i l e d D e s c r i p t i o n
8 Detailed Description
The AS1110 is designed to drive up to 16 LEDs through a fast serial interface and 16 constant-current output drivers.
Furthermore, the AS1110 provides diagnostics for detecting open- or shorted-LEDs, as well as over-temperature conditions for LED display systems, especially LED traffic sign applications.
The AS1110 contains an 16-bit shift register and an 16-bit data register, which convert serial input data into parallel output format. At AS1110 output stages, sixteen regulated current sinks are designed to provide uniform and constant current with excellent matching between ports for driving LEDs within a wide range of forward voltage variations. External
output current is adjustable from 0.5 to 100mA using an external resistor for flexibility in controlling the brightness
intensity of LEDs. The AS1110 guarantees to endure 15V maximum at the outputs.
The serial interface is capable of operating at a minimum of 30 MHz, satisfying the requirements of high-volume data
transmission.
Using a multiplexed input/output technique, the AS1110 adds additional functionality to pins SDO, LD and OEN. These
pins provide highly useful functions (open- and shorted-LED detection, over-temperature detection), thus reducing pin
count. Over-temperature detection will work on-the-run, whereas the open- and shorted-LED detection can be used
on-the-run or in low-current diagnostic mode (see page 15).
Figure 7. Block Diagram
Temperature
Detection
REXT
16-Bit Open
Detection &
Error Register
16-Bit Short
Detection &
Error Register
OUTN15
OUTN14
OUTN13
OUTN12
OUTN11
OUTN10
OUTN9
OUTN8
OUTN7
OUTN6
OUTN5
OUTN4
OUTN3
OUTN2
OUTN1
OUTN0
+VLED
AS1110
Current
Generators
OEN
LD
16-Bit Data
Register
CLK
Detailed
Error
Detection
Global
Error
Detection
16-Bit Shift
Register
SDI
Control Logic
SDO
Indicates 16 Bit Path
www.austriamicrosystems.com
Revision 1.00
8 - 24
AS1110
Data Sheet - D e t a i l e d D e s c r i p t i o n
Serial Interface
Data accesses are made serially via pins SDI and SDO. At each CLK rising edge, the signal present at pin SDI is
shifted into the first bit of the internal shift register and the other bits are shifted ahead of the first bit. The MSB is the
first bit to be clocked in. In error-detection mode the shift register will latch-in the corresponding error data of temperature-, open-, and short-error register with each falling edge of LD.
The 16-bit data register will latch the data of the shift register at each rising edge of LD. This data is then used to drive
the current generator output drivers to switch on the corresponding LEDs as OEN goes low.
Timing Diagrams
This section contains timing diagrams referenced in other sections of this data sheet.
Figure 8. Normal Mode Timing Diagram
tW(CLK)
50%
CLK
tSU(D)
SDI
50%
50%
50%
tH(D)
50%
SDO
50%
tP1
tW(L)
LD
50%
50%
tSU(L)
OEN
tH(L)
OEN Low = Output Enabled
OUTNx
OUTNx High = Output Off
50%
OUTNx Low = Output On
tP2
Figure 9. Output Delay Timing Diagram
tW(OE)
OEN
50%
50%
tP3
tP3
90%
90%
OUTN0
50%
tOR
tOF
tSTAG
tSTAG
50%
OUTN1
50%
14XtSTAG
50%
OUTN15
www.austriamicrosystems.com
Revision 1.00
50%
10%
10%
14XtSTAG
50%
9 - 24
AS1110
Data Sheet - D e t a i l e d D e s c r i p t i o n
Figure 10. Data Input Timing Diagram
OEN
tW(OE)
tSU(L)
LD
16 CLK Pulses
tSU(OE)
tW(L)
CLK
tSU(D)
Data Bit
15
SDI0
Data Bit
14
Data Bit
13
Data Bit
12
Data Bit Data Bit
n
2
Data Bit
1
Data Bit
0
Don’t Care
tH(D)
Old Data Old Data Old Data Old Data Old Data Old Data Old Data Old Data
Bit 15
Bit 14
Bit 13
Bit 12
Bit n
Bit 2
Bit 1
Bit 0
SDO0
Don’t Care
tP1
Figure 11. Data Input Example Timing Diagram
Time
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
CLK
SDI
D1 D14 D13 D12 D11 D10
LD
OEN
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
OUTN0
OUTN1
OUTN2
OUTN3
OUTN4
OUTN5
OUTN6
OUTN7
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
OUTN8
OUTN9
OUTN10
OUTN11
OUTN12
OUTN13
OUTN14
OUTN15
www.austriamicrosystems.com
Revision 1.00
10 - 24
AS1110
Data Sheet - D e t a i l e d D e s c r i p t i o n
Figure 12. Switching Global Error Mode Timing Diagram
OEN
tTESTING
tGSW(ERROR)
LD
tGSW(ERROR)
tSU(ERROR)
tP(I/O)
tP(I/O)
tP(I/O)
tGSW(ERROR)
CLK
TFLAG(IN)
SDI
Don’t
Care
SDO
Acquisition of
Error Status
tP4
OFLAG(IN)
TFLAG
Don’t
Care
OFLAG
tSW(ERROR)
SFLAG(IN)
Don’t
Care
SFLAG
tSW(ERROR)
Error-Detection Mode
Acquisition of the error status occurs at the rising edge of OEN. Error-detection mode is started on the rising edge of
LD when OEN is high. The CLK signal must be low when entering error detection mode. Error detection for open- and
shorted-LEDs can only be performed for LEDs that are switched on during test time. To switch between error-detection
modes clock pulses are needed (see Table 5).
Note: To test all LEDs, a test pattern that turns on all LEDs must be input to the AS1110.
Global Error Mode
Global error mode is entered when error-detection mode is started. Clock pulses during this period are used to select
between temperature, open-LED, and shorted-LED tests, as well as low-current diagnostic mode and shutdown mode
(see Table 5). In global error mode, an error flag (TFLAG, OFLAG, SFLAG) is delivered to pin SDO if any errors are
encountered.
Table 5. Global Error Mode Selections
Clock
Pulses Output Port
Error-Detection Mode
0
Don't Care
Over-Temperature
Detection
1
Enabled
Open-LED Detection
2
Enabled
Shorted-LED Detection
3
Don't Care
Low-Current Diagnostic
Mode
4
Don't Care
Shutdown Mode
Global Error Flag/Shutdown Condition
TFLAG = SDO = 1: No over-temperature warning.
TFLAG = SDO = 0: Over-temperature warning.
OFLAG = SDO = 1: No open-LED error.
OFLAG = SDO = 0: Open-LED error.
SFLAG = SDO = 1: No shorted-LED error.
SFLAG = SDO = 0: Shorted-LED error.
SDI = 1: Wakeup
SDI = 0: Shutdown
Note: For a valid result SDI must be 1 for the first device.
www.austriamicrosystems.com
Revision 1.00
11 - 24
AS1110
Data Sheet - D e t a i l e d D e s c r i p t i o n
If there are multiple AS1110s in a chain, the error flag will be gated through all devices. To get a valid result at the end
of the chain, a logic 1 must be applied to the SDI input of the first device of the chain. If one device produces an error
this error will show up after n*tP(I/O) + tSW(ERROR) at pin SDO of the last device in the chain. This means it is not possible to identify which device in the chain produced the error. Therefore, if a global error occurs, the detailed error report
can be run to identify which AS1110, or LED produced the error.
Note: When no error has occurred, the detailed error report can be skipped, setting LD and subsequently OEN low.
Error Detection Functions
Open-LED Detection
The AS1110 open-LED detection is based on the comparison between VDS and VTHL. The open LED status is aquired
at the rising edge of OEN and stored internally. While detecting open-LEDs the output port must be turned on. Open
LED detection can be started with 1 clock pulse during error detection mode while the output port is turned on.
Note: LEDs which are turned off at test time cannot be tested and will be shown as a logic 1 in the detailed error
report.
Table 6. Open LED Detection Modes
Output Port State
On
On
Effective Output
Point Conditions
VDS < VTHL
VDS > VTHL
Detected Open-LED
Error Status Code
0
1
Meaning
Open Circuit
Normal
Shorted-LED
The AS1110 shorted-LED detection is based on the comparison between VDS and VTHH. The shortened LED status is
aquired at the rising edge of OEN and stored internally. While detecting shorted-LEDs the output port must be turned
on. Shorted-LED detection can be started with 2 clock pulses during error detection mode while the output port is
turned on.
For valid results, the voltage at OUTN0:OUTN15 must be lower then VTHH under low-current diagnostic mode operating conditions. This can be achieved by reducing the VLED voltage or by adding additional diodes, resistors or LED’s.
Note: LEDs which are turned off at test time cannot be tested and will be shown as a logic 1 in the detailed error
report.
Table 7. Shorted LED Detection Modes
Output Port State
On
On
Effective Output
Point Conditions
VDS > VTHH
VDS < VTHH
Detected Shorted-LED
Error Status Code
0
1
Meaning
Short Circuit
Normal
Overtemperature
Thermal protection for the AS1110 is provided by continuously monitoring the device’s core temperature. The overtemperature status is aquired at the rising edge of OEN and stored internally.
Table 8. Overtemperature Modes
Output Port State
Effective Output
Point Conditions
Detected Overtemperature
Status Code
Meaning
Don’t Care
Temperature > TOV1
0
Don’t Care
Temperature < TOV1
1
Overtemperature
Condition
Normal
www.austriamicrosystems.com
Revision 1.00
12 - 24
AS1110
Data Sheet - D e t a i l e d D e s c r i p t i o n
Detailed Error Reports
The detailed error report can be read out after global error mode has been run. At the falling edge of LD, the detailed
error report of the selected test is latched into the shift register and can be clocked out with n*16 clock cycles (n is the
number of AS1110s in a chain) via pin SDO. At the same time new data can be written into the shift register, which is
loaded on the next rising edge of pin LD. This pattern is shown at the output drivers, at the falling edge of OEN.
Detailed Temperature Warning Report
The detailed temperature warning report can be read out immediately after global error mode has been run. SDI must
be 1 for the first device. Bit0 of the 16bit data word represents the temperature flag of the chip.
Figure 13. Detailed Temperature Warning Report Timing Diagram
Global Flag Readout
Detailed Error Report Readout
OEN
tH(L)
tGSW(ERROR)
LD
t(SU)ERROR
tP4
CLK
DBit15
SDI
DBit14 DBit13 DBit12
DBitn
DBit2
DBit1
DBit0
Don’t
Care
New Data Input
TFLAG
SDO
Undefined
Temperature Error Report Output
tP4
TBit0
Don’t
Care
tP1
For detailed timing information see Timing Diagrams on page 9.
Detailed Temperature Warning Report Example
Consider a case where four AS1110s are cascaded in one chain. The detailed error report lists the temperatures for
each device in the chain:
IC1:[70°] IC2:[85°] IC3:[170°] IC4:[60°]
In this case, IC3 is overheated and will generate a global error, and therefore 4*16 clock cycles are needed to write out
the detailed temperature warning report, and optionally read in new data. The detailed temperature warning report
would look like this:
XXXXXXXXXXXXXXX1 XXXXXXXXXXXXXXX1 XXXXXXXXXXXXXXX0 XXXXXXXXXXXXXXX1
The 0 in the detailed temperature warning report indicates that IC3 is the device with the over-temperature condition.
Note: In an actual report there are no spaces in the output.
www.austriamicrosystems.com
Revision 1.00
13 - 24
AS1110
Data Sheet - D e t a i l e d D e s c r i p t i o n
Detailed Open-LED Error Report
The detailed open-LED error report can be read out immediately after global error mode has been run. SDI must be 1
for the first device.
Figure 14. Detailed Open-LED Error Report Timing Diagram
Global Flag Readout
Detailed Error Report Readout
OEN
tTESTING
LD
tH(L)
tSU(ERROR)
tGSW(ERROR)
tP4
tGSW(ERROR)
CLK
SDI
SDO
Acquisition of
Error Status
tGSW(ERROR)
tSW(ERROR)
DBit15
DBit14 DBit13 DBit12 DBitn
DBit2
DBit1
Don’t
Care
DBit0
New Data Input
TFlag
OFlag
tP4
OBit15 OBit14 OBit13 OBit12 OBitn
OBit2
Open Error Report Output
OBit1
OBit0
Don’t
Care
tP1
For detailed timing information see Timing Diagrams on page 9.
Detailed Open-LED Error Report Example
Consider a case where three AS1110s are cascaded in one chain. A 1 indicates a LED is on, a 0 indicates a LED is off,
and an X indicates an open LED. The open-LED test is only applied to LEDs that are turned on. This test is used with
a test pattern where all LEDs are on at test time.
IC1:[1111111111111111] IC2:[111XX11111111X11] IC3:[1111111111111111]
IC2 has three open LEDs switched on due to input. 3*16 clock cycles are needed to write the entire error code out. The
detailed error report would look like this:
Input Data: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1111111111111111
1111111111111111
LED Status: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 XX1 1 1 1 1 1 1 1 X1 1
1111111111111111
Failure Code: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1110011111111011
1111111111111111
Comparing this report with the input data indicates that IC2 is the device with two open LEDs at position 4 and 5 and
one open LED at position 14. For such a test it is recommended to enter low-current diagnostic mode first (see LowCurrent Diagnostic Mode on page 15) to reduce screen flickering.
This test can be used also on-the-fly without using an all 1s test pattern (see Figure 18 on page 17).
Note: In an actual report there are no spaces in the output. LEDs turned off during test time cannot be tested and will
show a logic 1 in the detailed error report.
www.austriamicrosystems.com
Revision 1.00
14 - 24
AS1110
Data Sheet - D e t a i l e d D e s c r i p t i o n
Detailed Shorted-LED Error Report
The detailed shorted-LED error report can be read out immediately after global error mode has been run (see Global
Error Mode on page 11). SDI must be 1 for the first device.
Figure 15. Detailed Shorted-LED Error Report Timing Diagram
Global Flag Readout
Detailed Error Report Readout
OEN
tTESTING
LD
tSU(ERROR)
tH(L)
tGSW(ERROR)
tP4
tGSW(ERROR)
CLK
Acquisition of
Error Status
tGSW(ERROR)
SDI
SDO
DBit15
DBit14 DBit13 DBit12
tSW(ERROR)
TTFLAG
FLAG OFLAG
SFLAG
tP4
DBitn
DBit2
DBit1
Don’t
Care
DBit0
New Data Input
SBit15
SBit14 SBit13 SBit12
SBitn
SBit2
Shorted-LED Error Report Output
SBit1
SBit0
Don’t
Care
tP1
For detailed timing information see Timing Diagrams on page 9.
Detailed Shorted-LED Error Report Example
Consider a case where three AS1110s are cascaded in one chain. A 1 indicates a LED is on, a 0 indicates a LED is off,
and an X indicates a shorted LED. This test is used on-the-fly.
IC1:[11111XX111111111] IC2:[1111111111111111] IC3:[X100011111111111]
IC1 has two shorted LEDs which are switched on, IC3 has one shorted LED switched off due to input. 3*16 clock
cycles are needed to write the entire error code out. The detailed error report would look like this:
Input Data: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1111111111111111
0100011111111111
LED Status: 1 1 1 1 1 X X 1 1 1 1 1 1 1 1 1
1111111111111111
X1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Failure Code: 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1
1111111111111111
1111111111111111
Showing IC1 as the device with two shorted LEDs at position 6 and 7, and IC3 with one shorted LED at position 1. The
shorted LED at position 1 of IC3 cannot be detected, since LEDs turned off at test time are not tested and will show a
logic "1" at the detailed error report. To test all LEDs this test should be run with an all 1s test pattern. For a test with an
all on test pattern, low-current diagnostic mode should be entered first to reduce on-screen flickering.
Note: In an actual report there are no spaces in the output. LEDs turned off during test time cannot be tested and will
show a logic 1 in the detailed error report.
Low-Current Diagnostic Mode
To run the open- or shorted-LED test, a test pattern must be used that will turn on each LED to be tested. This test pattern will cause a short flicker on the screen while the test is being performed. The low-current diagnostic mode can be
initiated prior to running a detailed error report to reduce this on-screen flickering.
Note: Normally, displays using such a diagnostic mode require additional cables, resistors, and other components to
reduce the current. The AS1110 has this current-reduction capability built-in, thereby minimizing the number of
external components required.
Low-current diagnostic mode can be initiated via 3 clock pulses during error-detection mode. After the falling edge of
LD, a test pattern displaying all 1s can be written to the shift register which will be used for the next error-detection test.
www.austriamicrosystems.com
Revision 1.00
15 - 24
AS1110
Data Sheet - D e t a i l e d D e s c r i p t i o n
On the next falling edge of OEN, current is reduced to ILC. With the next rising edge of OEN the current will immediately increase to normal levels and the detailed error report can be read out entering error-detection mode.
Figure 16. Switching into Low-Current Diagnostic Mode Timing Diagram
Low-Current
Diagnosis Mode
OEN
tTESTING
LD
Load Internal all 1s
Test Pattern
(optional)
tSU(ERROR)
tGSW(ERROR)
tH(L)
CLK
tGSW(ERROR)
tSW(ERROR)
SDI
SDO
TFLAG OFLAG SFLAG
Re-entering Error
Detection Mode
(see Figure 14)
(see Figure 15)
Don’t
Care
Normal Operation Current
tP1
For detailed timing information see Timing Diagrams on page 9.
Shutdown Mode
The AS1110 features a shutdown mode which can be entered via 4 clock pulses during error-detection mode. To
enable the shutdown mode a 0 must be placed at SDI after the rising edge of the 3rd clock pulse.
To disable shutdown mode a 1 must be placed at SDI after the 3rd clock pulse. The shutdown/wakeup information will
be latched through if multiple AS1110 devices are in a chain. At the rising edge of the 4th clock pulse the shutdown bit
will be read out and the AS1110 will shutdown or wakeup.
Note: In shutdown mode the supply current drops down to <10µA.
Figure 17. Shutdown Mode Timing Diagram
OEN
LD
tSU(ERROR)
CLK
1 = Wakeup
SDI
0 = Shutdown
1 = Wakeup
SDO
TFLAG
OFLAG
SFLAG
0 = Shutdown
tP4
www.austriamicrosystems.com
tSU(D)
Revision 1.00
16 - 24
AS1110
Data Sheet - A p p l i c a t i o n I n f o r m a t i o n
9 Application Information
Error Detection
The AS1110 features two types of error detection. The error detection can be used on-the-fly, for active LEDs, without
any delay, or by entering into low-current diagnosis mode.
Error Detection On-The-Fly
Error detection on-the-fly will output the status of active LEDs during operation. Without choosing an error mode this
will output the temperature flag at every input/output cycle. Triggering one clock pulse for open or two clock pulses for
short detection during error detection mode outputs the detailed open- or short-error report with the next input/output
cycle (see Figure 18). LEDs turned off at test time are not tested and will show a logic "1" at the detailed error report.
Figure 18. Normal Operation with Error Detection During Operation – 64 Cascaded AS1110s
Display
Data1
Data2
SDI
Data2
Data3
SDO
T/O or S Error Code
Data0
CLK
OEN
Data3
Data4
T/O or S Error Code
Data1
GEF
Clock for Error
Mode 0x/1x/2x
T/O or S Error Code
Data2
GEF
Clock for Error
Mode 0x/1x/2x
1024x
1024x
1024x
Rising Edge of OEN
Acquisition of Error Status
Rising Edge of OEN
Acquisition of Error Status
Falling Edge of LD; Error Register is
copied into Shift Register
LD
Falling Edge of LD; Error Register is
copied into Shift Register
≤ 100mA
Current
GEF = Global Error Flag
Error Detection with Low-Current Diagnosis Mode
This unique feature of the AS1110 uses an internal all 1s test pattern for a flicker free diagnosis of all LEDs. This error
detection mode can be started at the end of each input cycle (see Figure 19).
Figure 19. Low-Current Diagnosis Mode with Internal All 1s Test Pattern – 64 Cascaded AS1110s
Low-Current Diagnosis Mode
Display
SDI
SDO
Data0
Data1
T/O or S Error Code
Data0
Data1
Data2
Data2
Data3
O or S Error Code from
GEF
All 1s Test Pattern
GEF
GEF
Temperature Error Code
3x Clocks Low- Clock for Error
Current Mode Mode 1x/2x
CLK
OEN
1024x
1024x
Rising Edge of OEN
Acquisition of Error Status
Use Internal All 1s Falling Edge of LD; Error Register
is copied into Shift Register
Test Pattern
LD
Current
1024x
≤ 100mA
≤ 100mA
≤ 0.8mA
www.austriamicrosystems.com
GEF = Global Error Flag
Revision 1.00
17 - 24
AS1110
Data Sheet - A p p l i c a t i o n I n f o r m a t i o n
The last pattern written into the shift register will be saved before starting low-current diagnosis mode and can be displayed immediately after the test has been performed.
Low-current diagnostic mode is started with 3 clock pulses during error detection mode. Then OEN should be enabled
for ≥2µs for testing. With the rising edge of OEN the LED test is stopped, and while LD is high the desired error mode
can be selected with the corresponding clock pulses. After LD and OEN go low again the previously saved pattern can
be displayed at the outputs.
With the next data input the detailed error code will be clocked out at pin SDO.
Note: See Figure 20 for use of an external test pattern.
Figure 20. Low-Current Diagnosis Mode with External Test Pattern – 64 Cascaded AS1110s
Low-Current Diagnosis Mode
Display
Data1
External all 1s
Test Pattern
SDI
SDO
Data2
Data2
T/O or S Error Code
Data0
CLK
O or S Error Code
from Test Pattern
GEF
3x Clocks
Low-Current
Mode
Data3
GEF
Temperature Error Code
Clock for Error
Mode 1x/2x
1024x
1024x
1024x
Rising Edge of OEN
Acquisition of Error Status
OEN
Falling Edge of LD; Error Register
is copied into Shift Register
LD
Current
≤ 100mA
≤ 100mA
≤ 0.8mA
GEF = Global Error Flag
Cascading Devices
To cascade multiple AS1110 devices, pin SDO must be connected to pin SDI of the next AS1110 (see Figure 21). At
each rising edge of CLK the LSB of the shift register will be written into the shift register SDI of the next AS1110 in the
chain.
Note: When n*AS1110 devices are in one chain, n*16 clock pulses are needed to latch-in the input data.
Figure 21. Cascading AS1110 Devices
SDI
SDI
AS1110 #1
CLK
LD
SDO
OEN
SDI
AS1110 #2
CLK
LD
SDO
OEN
SDI
AS1110 #n-1
CLK
LD
SDO
OEN
CLK
LD
OEN
www.austriamicrosystems.com
Revision 1.00
18 - 24
AS1110
Data Sheet - A p p l i c a t i o n I n f o r m a t i o n
Constant Current
In LED display applications, the AS1110 provides virtually no current variations from channel-to-channel and from
AS1110-to-AS1110. This is mostly due to 2 factors:
!
While IOUT ≥ 10mA, the maximum current skew is less than ±3% between channels and less than ±6% between
AS1110 devices.
!
In the saturation region, the characteristic curve of the output stage is flat (see Figure 5 on page 7). Thus, the output current can be kept constant regardless of the variations of LED forward voltages (VF).
Adjusting Output Current
The AS1110 scales up the reference current (IREF) set by external resistor (REXT) to sink a current (IOUT) at each output port. As shown in Figure 3 on page 7 the output current in the saturation region is extremely flat so that it is possible to define it as target current (IOUT TARGET). IOUT TARGET can be calculated by:
VREXT = 1.253V
IREF = VREXT/REXT (if the other end of REXT is connected to ground)
IOUT TARGET = IREF*15 = (1.253V/REXT)*15
(EQ 1)
(EQ 2)
(EQ 3)
Where:
REXT is the resistance of the external resistor connected to pin REXT.
VREXT is the voltage on pin REXT.
The magnitude of current (as a function of REXT) is around 50.52mA at 372Ω and 25.26mA at 744Ω. Figure 3 on
page 7 shows the relationship curve between the IOUT TARGET of each channel and the corresponding external resistor
(REXT).
Package Power Dissipation
The maximum allowable package power dissipation (PD) is determined as:
PD(MAX) = (TJ-TAMB)/RTH(J-A)
When 16 output channels are turned on simultaneously, the actual package power dissipation is:
PD(ACT) = (IDD*VDD) + (IOUT*Duty*VDS*16)
(EQ 4)
(EQ 5)
Therefore, to keep PD(ACT) ≤ PD(MAX), the maximum allowed output current as a function of duty cycle is:
IOUT = {[(TJ-TAMB)/RTH(J-A)]-(IDD*VDD)}/VDS/Duty/16
(EQ 6)
Where:
TJ = 150ºC
Delayed Outputs
The AS1110 has graduated delay circuits between outputs. These delay circuits can be found between OUTNn and
constant current block.
The fixed delay time is 20 ns (typ) where OUTN0 has no delay, OUTN1 has 20ns delay, OUTN2 has 40ns delay ...
OUTN15 has 300ns delay. This delay prevents large inrush currents, which reduce power supply bypass capacitor
requirements when the outputs turn on (see Figure 10 on page 10)
Switching-Noise Reduction
LED drivers are frequently used in switch-mode applications which normally exhibit switching noise due to parasitic
inductance on the PCB.
Load Supply Voltage
Considering the package power dissipation limits (see EQ 4:6), the AS1110 should be operated within the range of
VDS = 0.4 to 1.0V.
For example, if VLED is higher than 5V, VDS may be so high that PD(ACT) > PD(MAX) where VDS = VLED - VF. In this case,
the lowest possible supply voltage or a voltage reducer (VDROP) should be used. The voltage reducer allows
VDS = (VLED -VF) - VDROP.
Note: Resistors or zener diodes can be used as a voltage reducer as shown in Figure 22.
www.austriamicrosystems.com
Revision 1.00
19 - 24
AS1110
Data Sheet - A p p l i c a t i o n I n f o r m a t i o n
Figure 22. Voltage Reducer using Resistor (Left) and Zener Diode (Right)
Voltage Supply
Voltage Supply
}
VLED
VDROP
VDROP
{
VF
VF
VLED
VDS
VDS
AS1110
AS1110
www.austriamicrosystems.com
Revision 1.00
20 - 24
AS1110
Data Sheet - P a c k a g e D r a w i n g s a n d M a r k i n g s
10 Package Drawings and Markings
The AS1110 is available in a 28-pin QFN (5x5mm) package and a 24-pin SSOP package.
-A-
Figure 23. 28-pin QFN (5x5mm) Packagee
D
INDEX AREA
(D/2 xE/2)
D2
D2/2
D/2
-B-
aaa C 2x
-BSEE
DETAIL B
2
1
N N-1
INDEX AREA
(D/2 xE/2)
TOP VIEW
Datum A or B
6
SEE
DETAIL B
4
NXb
-A-
aaa C 2x
5
bbb
ddd
C A B
C
BTM VIEW
0.08 C
A
L1
ccc C
NX
0.45
0.03
Typ
0.75
0.02
0.20 REF
0.55
0.15
0.10
0.10
0.05
0.08
0.10
A3
A1
Terminal Tip
ODD TERMINAL SIDE
Min
0.70
0.00
SEATING
PLANE
-C-
SIDE VIEW
e
Symbol
A
A1
A3
L
L1
aaa
bbb
ccc
ddd
eee
ggg
E2
E
e
E2/2
NXL
E/2
4
5
Max
0.80
0.05
0.65
0.15
Notes
1, 2
1, 2
1, 2
1, 2
1, 2
1, 2
1, 2
1, 2
1, 2
1, 2
1, 2
Symbol
D BSC
E BSC
D2
E2
K
b
e
N
ND
NE
Min
3.00
3.00
0.20
0.18
Typ
5.00
5.00
3.15
3.15
0.25
0.50
28
7
7
Max
3.25
3.25
0.30
Notes
1, 2
1, 2
1, 2
1, 2
1, 2
1, 2, 5
1, 2
1, 2, 5
1, 2, 5
Notes:Unilateral coplanarity zone applies to the exposed heat sink slug as well as the terminals.
1.
2.
3.
4.
Dimensioning and tolerancing conform to ASME Y14.5M-1994.
All dimensions are in millimeters; angles in degrees.
N is the total number of terminals.
The terminal #1 identifier and terminal numbering convention shall conform to JEDEC 95 SPP-012. Details of terminal #1 identifier are optional but must be located within the zone indicated. The terminal #1 identifier may be either
a mold or marked feature.
5. Dimension b applies to metallized terminal and is measured between 0.15 and 0.30mm from terminal tip. If one end
of the terminal has the optional radius, the b dimension should not be measured in that radius area.
6. Dimensions ND and NE refer to the number of terminals on each D and E side, respectively.
www.austriamicrosystems.com
Revision 1.00
21 - 24
AS1110
Data Sheet - P a c k a g e D r a w i n g s a n d M a r k i n g s
Figure 24. 24-pin SSOP Package
Symbol
A
A1
A2
b
C
D
E
E1
e
h
L
θ
Min
Max
1.35
1.75
0.10
0.25
1.37
1.57
0.20
0.30
0.19
0.25
8.55
8.74
5.79
6.20
3.81
3.99
0.635 BSC
0.22
0.49
0.40
1.27
0º
8º
www.austriamicrosystems.com
Revision 1.00
22 - 24
AS1110
Data Sheet - O r d e r i n g I n f o r m a t i o n
11 Ordering Information
The device is available as the standard products shown in Table 9.
Table 9. Ordering Information
Type
Description
Delivery Form
Package
AS1110-BSSU
Constant-Current, 16-Channel LED Driver with
Diagnostics
Tubes
24-pin SSOP
AS1110-BSST
Constant-Current, 16-Channel LED Driver with
Diagnostics
Tape and Reel
24-pin SSOP
AS1110-BQFR
Constant-Current, 16-Channel LED Driver with
Diagnostics
Tray
28-pin QFN (5x5mm)
AS1110-BQFT
Constant-Current, 16-Channel LED Driver with
Diagnostics
Tape and Reel
28-pin QFN (5x5mm)
www.austriamicrosystems.com
Revision 1.00
23 - 24
AS1110
Data Sheet
Copyrights
Copyright © 1997-2007, 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.
All products and companies mentioned are trademarks or registered trademarks of their respective companies.
Disclaimer
Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification 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 lifesustaining equipment are specifically not recommended without additional processing by austriamicrosystems AG for
each application. For shipments of less than 100 parts the manufacturing flow might show deviations from the standard
production flow, such as test flow or test location.
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.
Contact Information
Headquarters
austriamicrosystems AG
A-8141 Schloss Premstaetten, Austria
Tel: +43 (0) 3136 500 0
Fax: +43 (0) 3136 525 01
For Sales Offices, Distributors and Representatives, please visit:
http://www.austriamicrosystems.com/contact
www.austriamicrosystems.com
Revision 1.00
24 - 24