TDA8046 Datasheet, PDF (26/48 Pages) NXP Semiconductors – Multi-mode QAM demodulator

Philips Semiconductors
Multi-mode QAM demodulator
Product specification
TDA8046
handbook, full pagewidth
B quadrant
111
010 101
Q
011 110
001 100
A quadrant
010
b5 b4 b3
101 111
110 100 000 000 001 011
I
011 001 000 000 100 110
111 101 100 001 101 010
010 110 011 111
C quadrant
D quadrant
MGG189
Bit allocation for 32-QAM: b5, b4 and b3; b2 = b1 = b0 = 0; b7 and b6 differentially decoded (see Table 3).
Fig.26 Demapping scheme 3; bit allocation: 32-QAM.
7.1.10.4 Demapping scheme 4; direct translation: HP8782B/K03
handbook, full pagewidth
Q
b3 b2 b1 b0
b4
b5
b6
b7
0000
0001
0010
0011
0100
0101
0110
0111
I
1000
1001
1010
1011
1100
1101
1110
1111
MGG196
Bit allocation for 256-QAM: b7, b6, b5, b4, b3, b2, b1, b0.
Fig.27 Demapping scheme 4; bit allocation: 256-QAM.
1996 Nov 19
26