www.ams.com/LED-Driver-ICs/AS1110

Revision 1.6

17 - 24

AS1110

Datasheet - Application In form atio n

9 Application Information

9.1 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.

9.1.1 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 19). LEDs turned off at test time are not tested and will show

a logic "1" at the detailed error report.

Figure 19. Normal Operation with Error Detection During Operation – 64 Cascaded AS1110s

9.1.2 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 20).

Figure 20. Low-Current Diagnosis Mode with Internal All 1s Test Pattern – 64 Cascaded AS1110s

Display

SDI

SDO

CLK

OEN

LD

Current

Data1

Data2

Data3

T/O or S Error Code

Data1

T/O or S Error Code Data0

Data0

T/O or S Error Code

Data2

1024x

1024x

1024x

Clock for Error

Mode 0x/1x/2x

Rising Edge of OEN

Acquisition of Error Status

Falling Edge of LD; Error Register is copied

into Shift Register

≤ 100mA

GEF

GEF

GEF = Global Error Flag

Falling Edge of LD; Error Register is copied

into Shift Register

Clock for Error

Mode 0x/1x/2x

Rising Edge of OEN

Acquisition of Error Status

Data2

Data3

Data4

Clock for Error Mode

1x/2x

3x Clocks Low-

Current Mode

GEF

1024x

1024x

Data0

Rising Edge of OEN

Acquisition of Error Status

Falling Edge of LD; Error Register is cop-

ied into Shift Register

GEF

O or S Error Code from

All 1s Test Pattern

Temperature Error Code

Use Internal All 1s Test

Pattern

≤ 100mA

≤ 100mA

SDI

SDO

CLK

OEN

LD

≤ 0.8mA

GEF = Global Error Flag

1024x

Data1

Data2

T/O or S Error Code

Data0

GEF

Display

Current

Low-Current Diagnosis Mode

Data2

Data3

Data1