ams AS1112 16-channel led driver with dot correction and greyscale pwm Datasheet

AS1112
Product Brief
16-Channel LED Driver with Dot Correction and
Greyscale PWM
1 General Description
2 Key Features
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 control and 64-step constant-current sink (dot correction).
The dot correction circuitry adjusts the brightness variations between the AS1112 channels and other LED drivers. Greyscale control and dot correction circuitry are
accessible via the SPI-compatible serial interface. A single external resistor sets the maximum current value of
all 16 channels.
The device features two error detection functions. 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 device
is in an overtemperature condition.
An additional power-down pin puts the AS1112 into a
40nA standby-mode.
The AS1112 is available in a 32-pin TQFN 5x5 mm
package.
!
!
16 Channels
Greyscale PWM Control: 12-Bit (4096 Steps)
!
Dot Correction: 6-Bit (64 Steps)
!
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
!
Controlled In-Rush Current
!
Data Transfer & PWM Clock Rate: up to 30 MHz
!
CMOS Level I/O
!
Diagnostic Features
- LED Open/Short Detection
- Overtemperature Flag
!
32-pin TQFN 5x5 mm Package
3 Applications
The device is ideal for mono-, multi-, and full-color LED
displays, LED signboards, and display backlights.
Figure 1. Block Diagram
1 CLK
26
IREF
Max OUTn
Current
2 SDI
Greyscale
Counter
Control
Greyscale
0 Register 11
12-Bit Greyscale
PWM Control
Dot Correction
0 Register 5
6-Bit Dot
Correction
Input
Shift
Register
Greyscale
12 Register 23
12-Bit Greyscale
PWM Control
Dot Correction
6 Register 11
6-Bit Dot
Correction
.
MODE
Open
LED
Detect
22
Constant Current
Driver
Input
Shift
Register
Delay
x1
OUT1
.
.
.
Open&Short LED Detection
.
.
Control
Constant Current
Driver
21
Greyscale
180 Register191
12-Bit Greyscale
PWM Control
Dot Correction
90 Register 95
6-Bit Dot
Correction
XERR
30
GND
OUT0
5
3
Thermal
Flag
Delay
x0
Open&Short LED Detection
Control
Status
Open LED Detect,
Overtemperature
Flag, Dot
Correction Data
27
Constant Current
Driver
4
Control
OEN
VCC
29 PD
VREF =
1.24V
24
GSCLK
31
32 LD
Delay
x15
OUT15
Open&Short LED Detection
23
AS1112
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AS1112
Product Brief
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 life-sustaining 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 1.01
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