Datasheet

AD9974
Rev. A | Page 42 of 52
COMPLETE REGISTER LISTING
All addresses and default values are expressed in hexadecimal. When an address contains less than 28 data bits, all remaining bits must be
written as 0s. All TESTMODE registers must be set to the specified values.
Table 22. AFE Registers
Address
Data Bit
Content
Default
Value
Update Name Description
0x00 [1:0] 3 SCK STANDBY
Standby Modes.
0 = normal operation.
1= band gap reference in standby.
2, 3 = total power-down.
[2] 1 REFBUF_PWRDN
Reference Buffer for REFT and REFB Power Control.
0 = REFT/REFB internally driven.
1 = REFT/REFB not driven.
[3] 1 CLAMPENABLE
Clamp Enable Control.
0 = disable black clamp.
1 = enable black clamp.
[5:4] 0 TESTMODE Test Operation Only. Set to 0.
[6] 0 PBLK_LVL
PBLK Level Control.
0 = blank to 0.
1 = blank to clamp level.
[7] 0 DCBYP
DC Restore Circuit Control.
0 = enable dc restore circuit during PBLK.
1 = bypass dc restore circuit during PBLK.
[9:8] 0 CDSMODE
CDS Operation.
0 = normal (inverting) CDS mode.
1 = sample and hold (SHA) mode.
2 = positive CDS mode.
3 = invalid, do not use.
[16:10] 0 TESTMODE Test Operation Only. Set to 0.
[27:17] Unused Set unused bits to 0.
0x01 [1:0] 0 SCK TESTMODE Test Operation Only. Set to 0.
[2] 0 GRAYENCODE
Gray Coding ADC Outputs.
0 = disable.
1 = enable.
[3] 0 TESTMODE Test Operation Only. Set to 0.
[4] 1 TESTMODE Test Operation Only. Set to 0.
[27:5] Unused Set unused bits to 0.
0x02 [0] 0 SCK TESTMODE Test Operation Only. Set to 0.
[27:1] Unused Set unused bits to 0.
0x03 [23:0] FFFFFF SCK TESTMODE Test Operation Only. Set to FFFFFF.
[27:24] Unused Set unused bits to 0.
0x04 [1:0] 1 VD CDSGAIN
CDS Gain Setting.
0 = −3 dB.
1 = 0 dB (default).
2 = +3 dB.
3 = +6 dB.
[27:2] Unused Set unused bits to 0.
0x05 [9:0] F VD VGAGAIN VGA Gain. 6 dB to 42 dB (0.035 dB per step).
[27:10] Unused Set unused bits to 0.
0x06 [9:0] 1EC VD CLAMPLEVEL Optical Black Clamp Level. 0 LSB to 1023 LSB (1 LSB per step).
[27:10] Unused Set unused registers to 0.
0x07 [27:0] 0 TESTMODE Test Operation Only. Set to 0 if this register is accessed.
0x08 [27:0] 0 TESTMODE Test Operation Only. Set to 0 if this register is accessed.
0x09 [27:0] 0 TESTMODE Test Operation Only. Set to 0 if this register is accessed.
0x0A [27:0] 0 TESTMODE Test Operation Only. Set to 0 if this register is accessed.
0x0B [27:0] 0 TESTMODE Test Operation Only. Set to 0 if this register is accessed.