Datasheet

Data Sheet AD9558
Rev. B | Page 93 of 104
Address Bits Bit Name Description
0x0C05
[7:4] Reserved Reserved.
[3:2]
Channel 1 output frequency
scale
Scales the selected output frequency (defined by Register 0x0C01[7:4]) for the Channel
Divider 1 output.
00 (default) = divide-by-1.
01 = divide-by-4.
10 = divide-by-8.
11 = divide-by-16.
[1:0]
Channel 0 output frequency
scale
Scale the selected output frequency (defined by Register 0x0C01[7:4]) for the Channel
Divider 0 output.
00 (default) = divide-by-1.
01 = divide-by-4.
10 = divide-by-8.
11 = divide-by-16.
0x0C06
[7:5] Reserved Reserved.
4 Sel high PM base loop filter 0 = base loop filter with normal (70°) phase margin (default).
1 = base loop filter with high (88.5°) phase margin.
(< 0.1 dB peaking in closed-loop transfer function).
[3:2] DPLL loop BW Scale the DPLL loop BW while in soft pin mode.
00 (default) = 50 Hz.
01 = 1 Hz.
10 = 10 Hz.
11 =100 Hz.
[1:0]
Reference input frequency
tolerance
Scales the input frequency tolerance while in soft pin mode.
00 (default) = outer tolerance: 10%; inner tolerance: 8% (for general conditions).
01 = outer tolerance: 12 ppm; inner tolerance: 9.6 ppm (for Stratum 3).
10 = outer tolerance: 48 ppm; inner tolerance: 38 ppm (for SMC clock standard).
11 = outer tolerance: 200 ppm; inner tolerance: 160 ppm (for XTAL system clock).
0x0C07
[7:1] Reserved Reserved.
0
Soft pin start transfer
Autoclearing register. 1 = initiates ROM download without resetting the part/register map.
After ROM download is complete, this register is reset.
0x0C08
[7:1] Reserved Reserved.
0
Soft pin reset
Autoclearing register; resets the part like soft reset (Register 0x0000[5]), except that this
reset function initiates a soft pin ROM download without resetting the part/register map.
After ROM download is complete, this register is pulled back to zero.
1
All bits in Register 0x0C00 to Register 0x0C06 take effect only with either a soft pin start transfer (Register 0x0C07) or soft pin reset (Register 0x0C08).
STATUS READBACK (REGISTER 0x0D00 TO REGISTER 0x0D14)
All bits in Register 0x0D00 to Register 0x0D14 are read only. To show the latest status, these registers require an I/O update (Register 0x0005 =
0x01) immediately before being read.
Table 101. EEPROM Status
Address Bits Bit Name Description
0x0D00 [7:4] Reserved Reserved.
3
Pin program ROM load process The control logic sets this bit when data is being read from the ROM.
2
Fault detected An error occurred while saving data to or loading data from the EEPROM.
1
Load in progress The control logic sets this bit while data is being read from the EEPROM.
0
Save in progress The control logic sets this bit while data is being written to the EEPROM.