Datasheet

Data Sheet AD9287
Rev. E | Page 25 of 52
Two output clocks are provided to assist in capturing data from
the AD9287. The DCO is used to clock the output data and is
equal to four times the sample clock (CLK) rate. Data is clocked
out of the AD9287 and must be captured on the rising and
falling edges of the DCO that supports double data rate (DDR)
capturing. The FCO is used to signal the start of a new output
byte and is equal to the sample clock rate. See the timing
diagram shown in Figure 2 for more information.
Table 9. Flexible Output Test Modes
Output Test Mode
Bit Sequence Pattern Name Digital Output Word 1 Digital Output Word 2
Subject to Data
Format Select
0000 Off (default) N/A N/A N/A
0001 Midscale short 1000 0000 (8-bit)
10 0000 0000 (10-bit)
1000 0000 0000 (12-bit)
10 0000 0000 0000 (14-bit)
Same Yes
0010 +Full-scale short 1111 1111 (8-bit)
11 1111 1111 (10-bit)
1111 1111 1111 (12-bit)
11 1111 1111 1111 (14-bit)
Same Yes
0011
−Full-scale short
0000 0000 (8-bit)
00 0000 0000 (10-bit)
0000 0000 0000 (12-bit)
00 0000 0000 0000 (14-bit)
Same
Yes
0100 Checkerboard 1010 1010 (8-bit)
10 1010 1010 (10-bit)
1010 1010 1010 (12-bit)
10 1010 1010 1010 (14-bit)
0101 0101 (8-bit)
01 0101 0101 (10-bit)
0101 0101 0101 (12-bit)
01 0101 0101 0101 (14-bit)
No
0101 PN sequence long
1
N/A N/A Yes
0110 PN sequence short
1
N/A N/A Yes
0111 One-/zero-word toggle 1111 1111 (8-bit)
11 1111 1111 (10-bit)
1111 1111 1111 (12-bit)
11 1111 1111 1111 (14-bit)
0000 0000 (8-bit)
00 0000 0000 (10-bit)
0000 0000 0000 (12-bit)
00 0000 0000 0000 (14-bit)
No
1000 User input Register 0x19 to Register 0x1A Register 0x1B to Register 0x1C No
1001 1-/0-bit toggle 1010 1010 (8-bit)
10 1010 1010 (10-bit)
1010 1010 1010 (12-bit)
10 1010 1010 1010 (14-bit)
N/A No
1010 1× sync 0000 1111 (8-bit)
00 0001 1111 (10-bit)
0000 0011 1111 (12-bit)
00 0000 0111 1111 (14-bit)
N/A No
1011 One bit high 1000 0000 (8-bit)
10 0000 0000 (10-bit)
1000 0000 0000 (12-bit)
10 0000 0000 0000 (14-bit)
N/A No
1100 Mixed frequency 1010 0011 (8-bit)
10 0110 0011 (10-bit)
1010 0011 0011 (12-bit)
10 1000 0110 0111 (14-bit)
N/A No
1
All test mode options except PN sequence short and PN sequence long can support 8- to 14-bit word lengths in order to verify data capture to the receiver.