Datasheet

AD9231
Rev. A | Page 31 of 36
MEMORY MAP REGISTER TABLE
All address and bit locations that are not included in Table 16 are not currently supported for this device.
Table 16.
Addr
(Hex)
Register
Name
Bit 7
(MSB) Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1
Bit 0
(LSB)
Default
Value
(Hex) Comments
Chip Configuration Registers
0x00 SPI port
configuration
(global)
0 LSB
first
Soft reset 1 1 Soft
reset
LSB
first
0 0x18 The nibbles are
mirrored so that
LSB- or MSB-first
mode registers
correctly, regardless
of shift mode
0x01 Chip ID (global) 8-bit chip ID bits [7:0]
AD9231 = 0x24
Unique chip ID used
to differentiate
devices; read only
0x02 Chip grade
(global)
Open Speed grade ID [6:4]
20 MSPS = 000
40 MSPS = 001
65 MSPS = 010
80 MSPS = 011
Open Unique speed
grade ID used to
differentiate
devices; read only
Device Index and Transfer Registers
0x05 Channel index Open Open Open Open Open Open ADC B
default
ADC A
default
0x03 Bits are set to
determine which
device on chip
receives the next
write command;
the default is all
devices on chip
0xFF Transfer Open Open Open Open Open Open Open Transfer 0x00 Synchronously
transfers data from
the master shift
register to the slave
Program Registers (May or May Not Be Indexed by Device Index)
0x08 Modes External
power-
down
enable
(local)
External pin function
0x00 full power-down
0x01 standby
(local)
Open Open 00 = chip run
01 = full power-
down
10 = standby
11 = chip wide
digital reset (local)
0x80 Determines various
generic modes of
chip operation
0x09 Clock (global) Open Open Open Open Open Duty
cycle
stabilize
0x00
0x0B Clock divide
(global)
Open Clock divider [2:0]
Clock divide ratio
000 = divide by 1
001 = divide by 2
010 = divide by 3
011 = divide by 4
100 = divide by 5
101 = divide by 6
110 = divide by 7
111 = divide by 8
0x00 The divide ratio is
the value plus 1
0x0D Test mode (local) User test mode
(local)
00 = single
01 = alternate
10 = single once
11 = alternate
once
Reset PN
long gen
Reset
PN
short
gen
Output test mode [3:0] (local)
0000 = off (default)
0001 = midscale short
0010 = positive FS
0011 = negative FS
0100 = alternating checkerboard
0101 = PN 23 sequence
0110 = PN 9 sequence
0111 = one/zero word toggle
1000 = user input
1001 = 1-/0-bit toggle
1010 = 1x sync
1011 = one bit high
1100 = mixed bit frequency
0x00 When set, the test
data is placed on
the output pins in
place of normal
data