AD9683
Data Sheet
Bit 1—Reserved
Bits[3:2]—ILAS mode
Bit 0—Enable fast detect output
Setting this bit high enables the output of the upper threshold
FD comparator to drive the FD output pin.
Fast Detect Upper Threshold (Address 0x47 and
Address 0x48)
Address 0x48, Bit 7—Reserved
Address 0x48, Bits[6:0]—Fast detect upper threshold[14:8]
Address 0x47, Bits[7:0]—Fast detect upper threshold[7:0]
These registers provide an upper limit threshold. The 15-bit
value is compared with the output magnitude from the ADC
block. If the ADC magnitude exceeds this threshold value, the
FD output pin is set when Bit 0 in Address 0x45 is set.
Fast Detect Lower Threshold (Address 0x49 and
Address 0x4A)
Address 0x4A, Bit 7—Reserved
Address 0x4A, Bits[6:0]—Fast detect lower threshold[14:8]
Address 0x49, Bits[7:0]—Fast detect lower threshold[7:0]
These registers provide a lower limit threshold. The 15-bit value is
compared with the output magnitude from the ADC block. If the
ADC magnitude is less than this threshold value for the number
of cycles programmed in the fast detect dwell time register, the
FD output bit is cleared.
Fast Detect Dwell Time (Address 0x4B and
Address 0x4C)
Address 0x4C, Bits[7:0]—Fast Detect Dwell Time[15:8]
Address 0x4B, Bits[7:0]—Fast Detect Dwell Time[7:0]
These register values set the minimum time in ADC sample
clock cycles (after clock divider) that a signal needs to stay below
the lower threshold limit before the FD output bits are cleared.
JESD204B Quick Configuration (Address 0x5E)
Bits[7:0]—JESD204B quick configuration
01 = initial lane alignment sequence enabled.
11 = initial lane alignment sequence always on in test mode;
JESD204B data link layer test mode where the repeated lane
alignment sequence (as specified in JESD204B 5.3.3.8.2) is sent on
all lanes.
Bit 1—Reserved; set to 1
Bit 0—JESD204B link power-down
If Bit 0 is set high, the serial transmit link is held in reset with its
clock gated off. The JESD204B transmitter must be powered
down when changing any of the link configuration bits.
JESD204B Link Control 2 (Address 0x60)
Bits[7:5]—Reserved; set to 0
Bit 4—SYNCINB± logic type
0 = LVDS differential pair SYNCINB± input (default).
1 = CMOS single-ended SYNCINB± using the SYNCINB− input.
Bit 3—Open
Bit 2—Reserved; set to 0
Bit 1—Invert transmit bits
Setting this bit inverts the 10 serial output bits. This effectively
inverts the output signals.
Bit 0—Reserved; Set to 0
JESD204B Link Control 3 (Address 0x61)
Bit [7:6]—Reserved; set to 0
Bits[5:4]—Test data injection point
01 = 10-bit test generation data injected at output of 8B/10B
encoder (at input to PHY).
10 = 8-bit test generation data injected at input of scrambler
Bits[3:0]—JESD204B test mode patterns
0000 = normal operation (test mode disabled).
These bits serve to quickly set up the default JESD204B link
parameters for M = 1 and L = 1.
JESD204B Link Control 1 (Address 0x5F)
Bit 7—Open
Bit 6—Serial tail bit enable
If this bit is set and the CS bits are not enabled, unused tail bits are
padded with a pseudorandom number sequence from a 9-bit
LFSR (see JESD204B 5.1.4).
Bit 5—JESD204B test sample enable
If set, JESD204B test samples are enabled, and the long transport
layer test sample sequence (as specified in JESD204B Section
5.1.6.3) sent on all link lanes.
0001 = alternating checkerboard.
0010 = 1/0 word toggle.
0011 = PN23 sequence.
0100 = PN9 sequence.
0101 = continuous/repeat user test mode. The most significant
bits from the user pattern (1, 2, 3, 4) are placed on the output for
one clock cycle and then the output user pattern is repeated (1,
2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4….).
0110 = single user test mode. The most significant bits from the
user pattern (1, 2, 3, 4) are placed on the output for one clock
cycle, and then all zeros are output (output user pattern 1, 2, 3, 4;
then output all zeros).
Bit 4—Reserved; set to 1
0111 = reserved.
1100 = PN7 sequence.
1101 = PN15 sequence.
Others = unused.
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