Datasheet

AFE5804

www.ti.com

SBOS442C –JUNE 2008–REVISED OCTOBER 2011

LVDS TEST PATTERNS

ADDRESS

IN HEX D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 NAME

X 0 0 EN_RAMP

0 X 0 DUALCUSTOM_PAT

25 0 0 X SINGLE_CUSTOM_PAT

X X BITS_CUSTOM1<11:10>

X X BITS_CUSTOM2<11:10>

26 X X X X X X X X X X BITS_CUSTOM1<9:0>

27 X X X X X X X X X X BITS_CUSTOM2<9:0>

0 X PAT_DESKEW

X 0 PAT_SYNC

The AFE5804 can output a variety of test patterns on the LVDS outputs. These test patterns replace the normal

ADC data output. Setting EN_RAMP to '1' causes all the channels to output a repeating full-scale ramp pattern.

The ramp increments from zero code to full-scale code in steps of 1LSB every clock cycle. After hitting the

full-scale code, it returns back to zero code and ramps again.

The device can also be programmed to output a constant code by setting SINGLE_CUSTOM_PAT to '1', and

programming the desired code in BITS_CUSTOM1<11:0>. In this mode, BITS_CUSTOM<11:0> take the place of

the 12-bit ADC data at the output, and are controlled by LSB-first and MSB-first modes in the same way as

normal ADC data are.

The device may also be made to toggle between two consecutive codes by programming DUAL_CUSTOM_PAT

to '1'. The two codes are represented by the contents of BITS_CUSTOM1<11:0> and BITS_CUSTOM2<11:0>.

In addition to custom patterns, the device may also be made to output two preset patterns:

1. Deskew patten: Set using PAT_DESKEW, this mode replaces the 12-bit ADC output D<11:0> with the

010101010101 word.

2. Sync pattern: Set using PAT_SYNC, the normal ADC word is replaced by a fixed 111111000000 word.

Note that only one of the above patterns should be active at any given instant.