Datasheet
AS1112
16-Channel LED Driver with Dot Correction and
Greyscale PWM
1 General Description
2 Key Features
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16 Channels
The AS1112 is a 16-channel, constant current-sink LED
driver. Each of the 16 channels can be individually
adjusted by 4096-step greyscale PWM brightness con-
trol and 64-step constant-current sink (dot correction).
Greyscale PWM Control: 12-Bit (4096 Steps)
Dot Correction: 6-Bit (64 Steps)
The dot correction circuitry adjusts the brightness varia-
tions between the AS1112 channels and other LED driv-
ers. Greyscale control and dot correction circuitry are
accessible via the SPI-compatible serial interface. A sin-
gle external resistor sets the maximum current value of
all 16 channels.
Drive Capability (Constant-Current Sink): 0 to 80mA
LED Power Supply Voltage: Up to 15V
Supply Voltage Range: 3.0 to 5.5 V
SPI-Compatible Serial Interface
The open & short LED detection function indicates a
broken, shorted or disconnected LED at one or more of
the outputs. The overtemperature flag indicates that the
Controlled In-Rush Current
Data Transfer & PWM Clock Rate: up to 30 MHz
CMOS Level I/O
device is in an overtemperature condition.
Table 1. Standard Products
Diagnostic Features
- LED Open/Short Detection
- Overtemperature Flag
Model
AS1112
AS1112B
Power-Down
TEST pin
Yes
No
Connect to GND
Connect to VCC
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32-pin TQFN 5x5 mm Package
An additional power-down pin puts the AS1112 into a
40nA standby-mode.
3 Applications
The device is ideal for mono-, multi-, and full-color LED
displays, LED signboards, and display backlights.
The AS1112 is available in a 32-pin TQFN 5x5 mm
package.
Figure 1. Block Diagram
1
CLK 2 SDI
32 LD
29 PD
Constant Current
Driver
Control
26
Max OUTn
Current
VREF =
1.24V
4
IREF
Greyscale
Register 11
12-Bit Greyscale
PWM Control
Delay
x0
OUT0
0
24
Dot Correction
Register
6-Bit Dot
Correction
Greyscale
Counter
GSCLK
31
Control
0
5
Input
Shift
Register
Open&Short LED Detection
OEN
Constant Current
Driver
Control
Status
Open LED Detect,
Overtemperature
Flag, Dot
5
Greyscale
12 Register 23
12-Bit Greyscale
PWM Control
Delay
x1
OUT1
Correction Data
Dot Correction
Register 11
6-Bit Dot
Correction
.
.
.
3
MODE
27
6
.
Open&Short LED Detection
Open
Thermal
LED
.
.
Constant Current
Driver
Control
VCC
Flag
Detect
Input
Shift
Register
21
Greyscale
180 Register191
12-Bit Greyscale
PWM Control
Delay
x15
OUT15
Dot Correction
90 Register 95
6-Bit Dot
Correction
22
XERR
30
Open&Short LED Detection
23
AS1112
GND
SDO
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Revision 1.06
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