ISL5416 Datasheet, PDF (49/71 Pages) Intersil Corporation – Four-Channel Wideband Programmable DownConverter

ISL5416
P(31:0)
16
15
14:13
12
11:10
9
8
7
6
5:3
TABLE 52. CHANNEL PROCESSING CONTROL (IWA = *001h) RESET STATE = 0x00000000h (Continued)
FUNCTION
PN NOISE ENABLE. PN noise is added to the output of the mixer at the level selected in location IWA = *006h. This bit enables the
PN generator to the channel. When 0, IWA = *006h will be a DC offset.
1 = PN added to the mixer output.
0 = PN disabled.
CIC FILTER ENABLE.
1 = CIC filter enabled (minimum decimation is 2).
0 = CIC filter disabled (the CIC shifter is used for floating point to fixed point conversion).
CIC TO FIR1 GAIN ADJUST. The 24-bit output from the NCO/Mixer/CIC Block to FIR1 is scaled and rounded to 20 bits. Saturation
detection is included. This gain stage is always present in the data path.
00 = x1.
01 = x2.
10 = x4.
11 = x8.
FIR1 ENABLE.
1 = FIR1 enabled.
0 = FIR1 bypassed.
FIR1 TO FIR2 GAIN ADJUST. The 24-bit output from the FIR1 Block to FIR2 is scaled and rounded to 20 bits. Saturation detection
is included. This gain stage is always present in the data path.
00 = x1.
01 = x2.
10 = x4.
11 = x8.
FIR2 ENABLE.
1 = FIR2 enabled.
0 = FIR2 bypassed.
INTERPOLATION HALF BAND FILTER ENABLE.
1 = IHBF enabled.
0 = IHBF bypassed.
RESAMPLER ENABLE.
1 = Resampler enabled.
0 = Resampler bypassed.
LEAP COUNTER ENABLE.
1 = Resampler leap counter enabled.
0 = Resampler leap counter disabled.
I/Q OUTPUT ROUNDING. I and Q data busses to the output section are rounded to the selected number of MSBs. Bits below the
programmed number of bits are zeroed.
000 = 24 bits, data on bits 23:0.
001 = 20 bits, data on bits 23:4, bits 3:0 zeroed.
010 = 16 bits, data on bits 23:8, bits 7:0 zeroed.
011 = 12 bits, data on bits 23:12, bits 11:0 zeroed.
100 = 8 bits, data on bits 23:16, bits 15:0 zeroed.
101 = 6 bits, data on bits 23:18, bits 17:0 zeroed.
110 = 4 bits, data on bits 23:20, bits 19:0 zeroed.
111 = reserved.
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