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 www.austriamicrosystems.com SDO Revision 1.01 1-2 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 2-2