SLASEC1B March 2016 – May 2018 TAS5751M
PRODUCTION DATA.
All mixer gain coefficients are 26-bit coefficients using a 3.23 number format. Numbers formatted as 3.23 numbers mean that the binary point has 3 bits to the left and 23 bits to the right. This is shown in Figure 64.
The decimal value of a 3.23 format number can be found by following the weighting shown in Figure 64. If the most significant bit is logic 0, the number is a positive number, and the weighting shown yields the correct number. If the most significant bit is a logic 1, then the number is a negative number. In the case every bit must be inverted, a 1 added to the result, and then the weighting shown in Figure 65 applies to obtain the magnitude of the negative number.
Gain coefficients, entered via the I²C bus, must be entered as 32-bit binary numbers. The format of the 32-bit number (4-byte or 8-digit hexadecimal number) is shown in Figure 66.
db | Linear | Decimal | Hex (3.23 Format) |
---|---|---|---|
0 | 1 | 8,388,608 | 80 0000 |
5 | 1.77 | 14,917,288 | 00E3 9EA8 |
–5 | 0.56 | 4,717,260 | 0047 FACC |
X | L = 10(X / 20) | D = 8,388,608 × L | H = dec2hex (D, 8) |
db | Linear | Decimal | Hex (9.17 Format) |
---|---|---|---|
0 | 1 | 131,072 | 2 0000 |
5 | 1.77 | 231,997 | 3 8A3D |
–5 | 0.56 | 73,400 | 1 1EB8 |
X | L = 10(X / 20) | D = 131,072 × L | H = dec2hex (D, 8) |