Datasheet

Data Sheet AD9148
Rev. B | Page 31 of 72
Register Name
Addr
(Hex) Bit Name Function Default
FIFO Status Port A 18 7:0 FIFO Level Thermometer encoded measure of the FIFO level.
Read-
only
FIFO Status/
Control Port B
19 7 FIFO Warning 1 FIFO read and write pointers within ±1.
Read-
only
6
FIFO Warning 2
FIFO read and write pointers within ±2.
Read-
only
5 FIFO reset aligned FIFO read and write pointers aligned after chip reset.
Read-
only
4
FIFO SPI align
acknowledge
FIFO read and write pointers aligned after SPI driven FIFO
reset.
Read-
only
3
FIFO SPI align
requesting
Request FIFO read and write pointers alignment via SPI. 0
2:0 FIFO phase offset
FIFO read and write pointer phase offset from optimal
phase following FIFO reset.
000
000 = 0 offset from optimal phase.
…
111 = 7 offset from optimal phase.
The optimal value is 0.
FIFO Status Port B 1A 7:0 FIFO level Thermometer encoded measure of the FIFO level.
Read-
only
HB1 Control 1C 7 Enable pre mod
Enable fS/2 modulation stage that precedes Stage 1
interpolation filter.
0
6 Bypass sinc-1 Sinc-1 filter bypass. 1
2:1 HB1[1:0]
Modulation mode for first stage interpolation filter
(f
HB1
= 2 × f
IN1
).
00
00 = input signal modulated by dc. Filter pass band is
from −0.2 to +0.2 of f
HB1
.
01 = input signal modulated by dc. Filter pass band is
from 0.05 to 0.45 of f
HB1
.
10 = input signal modulated by f
HB1
/2. Filter pass band is
from 0.3 to 0.7 of f
HB1
.
11 = input signal modulated by f
HB1
/2. Filter pass band is
from 0.55 to 0.95 of f
HB1
.
0 Bypass HB1 First stage interpolation filter bypass. 0