AnsweredAssumed Answered

Unsharp image when heating AD9984A

Question asked by IvanRusov on Feb 20, 2012
Latest reply on Apr 10, 2012 by GuenterL

Hello everybody.


I have a problem with Display Interface AD9984A (chip revision 0x00). I use input signal resolution 1600x1200x60Hz.


In normal condition I see more-less sharp test image. Oscillogram and Image from monitor are shown in fig1.jpg and 1600_1200_60_1.bmp respectively.

When I heat a board with AD9984A by foehn I see DATACK drift relatively Hsync (input) and test image become less sharp. Oscillogram and Image from monitor are shown in fig2.jpg and 1600_1200_60_2.bmp respectively. As you can see that DATACK drift is approximately 3 ns.


Could you tell me please, it's a normal situation for AD9984A or I'd made mistake? Thank you.


Oscilliscope configuration (input BW is 200 MHz).

1ch (Orange) - VSYNC(input)

4ch (Green) - HSYNC(input)

2ch (Blue) - DATACK(output)

3ch (Magenta) - HSOUT(output)

Oscilloscope are synchronized from VSYNC.


Current Register Configuration:

Reg#     Reg Data

0x01     0x87

0x02     0x00

0x03     0xF0

0x04     0x60

0x05     0x41

0x06     0x00

0x07     0x41

0x08     0x00

0x09     0x41

0x0A     0x00

0x0B     0x54

0x0C     0x00

0x0D     0x54

0x0E     0x00

0x0F     0x54

0x10     0x00

0x11     0x20

0x12     0x98

0x13     0x10

0x14     0x8E

0x15     0x30

0x16     0x00

0x17     0x00

0x18     0x20

0x19     0x08

0x1A     0x20

0x1B     0x43

0x1C     0xFF

0x1D     0xFD

0x1E     0xA5

0x1F     0x95

0x20     0x07

0x21     0x20

0x22     0x32

0x23     0x1F

0x28     0xBF

0x29     0x02

0x2C     0x00

0x2D     0xE8

0x2E     0xE0

0x34     0x04

0x3C     0x0E