AS1121-BQFT austriamicrosystems, AS1121-BQFT Datasheet
AS1121-BQFT
Specifications of AS1121-BQFT
Related parts for AS1121-BQFT
AS1121-BQFT Summary of contents
Page 1
... The open LED detection function indicates a broken or disconnected LED at one or more of the outputs. The overtemperature protection- flag indicates that the device overtemperature condition. An additional power-down pin puts the AS1121 into a 40nA standby- mode. The AS1121 is available in a 32-pin TQFN 5x5 mm package. Figure 1. AS1121 - Block Diagram 26 Max OUTn V ...
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... LD For LD (MODE = V Thermal Pad. This pin must be connected to GND to ensure normal operation. 33 Thermal Pad www.austriamicrosystems.com/LED-Driver-ICs CLK 1 24 GSCLK SDI 2 23 SDO 3 22 XERR AS1121 4 21 OUT15 Thermal 5 20 OUT14 Pad 6 19 OUT13 7 18 OUT12 OUT11 Description (see Setting Greyscale Brightness on page 11) ...
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... AS1121 Datasheet - 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 maximum rating conditions for extended periods may affect device reliability. ...
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... AS1121 Datasheet - Electrical Characteristics V = +3.1V to +3.6V, Typical values are AMB with min and max values are guaranteed with production tests or SQC (Statistical Quality Control) methods.. Table 3. Electrical Characteristics Symbol Parameter T Operating Temperature Range AMB T Operating Junction Temperature J Input Supply V Supply Voltage ...
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... AS1121 Datasheet - Table 3. Electrical Characteristics (Continued) Symbol Parameter I Low-Level Output Current OL LED Open Detection Threshold V LOD Reference Voltage Output V IREF Timing Characteristics V = +3.1V to +3.6V -40°C to +85ºC. Typical values are AMB Table 4. Output Tming Characteristics Symbol Parameter t R0 Rise Time Fall Time ...
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... AS1121 Datasheet - Table 5. Serial Interface Timing Characteristics Symbol Parameter t SU0 t SU1 t Setup Time SU2 t SU3 t SU4 Hold Time See Figure 6 on page 10. 2. See Figure 10 on page 13. 3. See Figure 4 on page 8 4. See Figure 8 on page 11. 5. See Figure 3 on page 7 ...
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... Multiple AS1121 devices can be cascaded by connecting the SDO pin of one device with pin SDI of the next device The SDO pin can also be connected to the microcontroller to receive status information from the AS1121. The serial data format is 96-bit or 192- bit wide, depending on mode of the device (see LD on page Figure 3 ...
Page 8
... To differentiate the the open LED from the overtemperature condition the status information data (SID) of the AS1121 needs to be read out. Open LED Detection The AS1121 integrated open LED detection circuit reports an error if any of the 16 LEDs is open or disconnected from the circuit. The open LED detection circuit trips when the error detection is activated and the voltage at OUTn is less than V Note: The voltage at each OUTn is sampled 1 µ ...
Page 9
... Where 1.27V; IREF R = User-selected external resistor. IREF Power Dissipation To ensure proper operation of the device, the total power dissipation of the AS1121 must be below the power dissipation rating of the device package. Total power dissipation is calculated as Where the device supply voltage the device supply current; ...
Page 10
... AS1121 Datasheet - Setting Dot Correction The AS1121 can perform independent fine-adjustments to the output current of each channel, i.e., dot correction. Dot correction is used to adjust brightness deviations of LEDs connected to the output channels (OUT0:OUT15). The device powers up with the following default seetings and GS = 4095. ...
Page 11
... GS14.11 GS OUT15 When pin MODE is tied to GND, the AS1121 enters greyscale data input mode. The device switches the input shift register to 192-bit width. After all data is clocked in, the rising edge of the LD signal latches the data into the greyscale register All greyscale data in the input shift register is replaced with status information data (SID) after latching into the greyscale register. ...
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... Datasheet - Status Information Data (SID) The AS1121 contains an integrated status information register, which can be accessed in greyscale mode (MODE = GND). Once the LD signal latches the data into the greyscale register, the input shift register data is replaced with status information data The Open LED information as well as the dot-correction registers can be read out at pin SDO. The status information data packet is 192 bits wide ...
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... XERR Output Delay To minimize the ripple on the inrush current, the outputs are delayed and are not switching at the same time. The 16 channels of the AS1121 are combined in groups of 4. The channels within the groups OUT0:OUT3, OUT4:OUT7, OUT8:OUT11, OUT12:OUT15 are switching at the same time ...
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... GSCLK MODE MODE OEN OEN SOUT Controller The maximum number of cascading AS1121 devices depends on the application system and is in the range of 40 devices. The minimum fre- quency needed can be calculated by the following equations: Where the minimum frequency needed for GSCLK; GSCLK f is the update rate of whole cascaded system ...
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... AS1121 Datasheet - Package Drawings and Markings Figure 12. 32-pin TQFN 5x5 mm Marking Figure 13. Packaging Code YYWWIZZ YY last two digits of the current year www.austriamicrosystems.com/LED-Driver-ICs WW I plant identifier manufacturing week Revision 1.00 ZZ free choice / traceability code ...
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... AS1121 Datasheet - Figure 14. 32-pin TQFN 5x5 mm Package www.austriamicrosystems.com/LED-Driver-ICs Revision 1. ...
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... Datasheet - Ordering Information The device is available as the standard products shown in Table 8. Ordering Information Ordering Code Marking 16-Channel LED Driver with Dot Correction and AS1121-BQFT AS1121 16-Channel LED Driver with Dot Correction and AS1121B-BQFT* AS1121B *) on request Note: All products are RoHS compliant. ...
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... AS1121 Datasheet Copyrights Copyright © 1997-2011, austriamicrosystems AG, Tobelbaderstrasse 30, 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. ...