Datasheet
AD9287 Data Sheet
Rev. E | Page 32 of 52
Table 16. Memory Map Register
Addr.
(Hex)
Register Name
(MSB)
Bit 7
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1
(LSB)
Bit 0
Default
Value
(Hex)
Default Notes/
Comments
Chip Configuration Registers
00 chip_port_config 0
LSB first
1 = on
0 = off
(default)
Soft
reset
1 = on
0 = off
(default)
1 1
Soft
reset
1 = on
0 = off
(default)
LSB first
1 = on
0 = off
(default)
0 0x18
The nibbles
should be
mirrored so that
LSB- or MSB-first
mode is set cor-
rectly regardless
of shift mode.
01 chip_id
8-bit Chip ID Bits [7:0]
(AD9287 = 0x05), (default)
0x05
Default is unique
chip ID, different
for each device.
This is a read-
only register.
02 chip_grade X
Child ID [6:4]
(identify device variants of Chip ID)
011 = 100 MSPS
X X X X
Read
only
Child ID used to
differentiate
graded devices.
Device Index and Transfer Registers
05 device_index_A X X
Clock
Channel
DCO
1 = on
0 = off
(default)
Clock
Channel
FCO
1 = on
0 = off
(default)
Data
Channel
D
1 = on
(default)
0 = off
Data
Channel
C
1 = on
(default)
0 = off
Data
Channel
B
1 = on
(default)
0 = off
Data
Channel
A
1 = on
(default)
0 = off
0x0F
Bits are set to
determine which
on-chip device
receives the next
write command.
FF device_update X X X X X X X
SW
transfer
1 = on
0 = off
(default)
0x00
Synchronously
transfers data
from the master
shift register to
the slave.
ADC Functions
08 modes X X X X X
Internal power-down mode
000 = chip run (default)
001 = full power-down
010 = standby
011 = reset
0x00
Determines
various generic
modes of chip
operation.
09 clock X X X X X X X
Duty
cycle
stabilizer
1 = on
(default)
0 = off
0x01
Turns the
internal duty
cycle stabilizer
on and off.
0D test_io
User test mode
00 = off (default)
01 = on, single alternate
10 = on, single once
11 = on, alternate once
Reset
PN long
gen
1 = on
0 = off
(default)
Reset
PN short
gen
1 = on
0 = off
(default)
Output test mode—see Table 9
i
n the
Digital Outputs and Timing
section
00
00 = off (default)
0001 = midscale short
0010 = +FS short
0011 = −FS short
0100 = checkerboard output
0101 = PN 23 sequence
0110 = PN 9 sequence
0111 = one-/zero-word toggle
1000 = user input
1001 = 1-/0-bit toggle
1010 = 1× sync
1011 = one bit high
1100 = mixed bit frequency
(format determined by output_mode)
0x00
When this reg-
ister is set, the
test data is placed
on the output
pins in place of
normal data.