Rainbow Electronics MAX12553 - Manual (Page 21)

MAX12553
14-Bit, 65Msps, 3.3V ADC
______________________________________________________________________________________ 21
BINARY-TO-GRAY CODE CONVERSION
1) THE MOST SIGNIFICANT GRAY CODE BIT IS THE SAME
AS THE MOST SIGNIFICANT BINARY BIT.
2) SUBSEQUENT GRAY CODE BITS ARE FOUND ACCORDING
TO THE FOLLOWING EQUATION:
BINARY
GRAY CODE
BIT POSITION
3) REPEAT STEP 2 UNTIL COMPLETE.
BINARY
GRAY CODE
BIT POSITION
4) THE FINAL GRAY CODE CONVERSION IS:
BINARY
BIT POSITION
GRAY-TO-BINARY CODE CONVERSION
WHERE IS THE EXCLUSIVE OR FUNCTION (SEE TRUTH
TABLE BELOW) AND X IS THE BIT POSITION.
0 1 1 1 0 1 0 0 1 1 0 0
0
D11 D7 D3 D0
1
D13
1 0
0 1 1 1 0 1 0 0 1 1 0 0
0
D11 D7 D3 D0
1
1 0
0
D13
0 1 1 1 0 1 0 0 1 1 0 0
D11 D7 D3 D0
1 0
D13
1 0 1 1 0 1 0 0 1 1 0 0 BINARY
GRAY CODE 0
D11 D7 D3 D0 BIT POSITION
0 1
D13
GRAY CODE 0 1 0 1 1 0 1 1 1 0 1 0 1 0
GRAY
X
= BINARY
X
BINARY
X+1
GRAY
12
= BINARY
12
BINARY
13
GRAY 12 = 1 0
GRAY 12 = 1
GRAY 11 = BINARY 11 BINARY 12
GRAY
11
= 1 1
GRAY 11 = 0
1) THE MOST SIGNIFICANT BINARY BIT IS THE SAME
AS THE MOST SIGNIFICANT GRAY CODE BIT.
2) SUBSEQUENT BINARY BITS ARE FOUND ACCORDING
TO THE FOLLOWING EQUATION:
GRAY CODE
BINARY
BIT POSITION
3) REPEAT STEP 2 UNTIL COMPLETE.
GRAY CODE
BINARY
BIT POSITION
4) THE FINAL GRAY CODE CONVERSION IS:
GRAY CODE
BIT POSITION
WHERE IS THE EXCLUSIVE OR FUNCTION (SEE TRUTH
TABLE BELOW) AND X IS THE BIT POSITION.
0 1 0 0 1 1 1 0 1 0 1 0
0
D11 D7 D3 D0
1
0
1 1
D13
1 1
0 1 0 1 1 1 0 1 0 1 0
0
D11 D7 D3 D0
1 1
D13
0 1 0 0 1 1 1 0 1 0 1 0
D11 D7 D3 D0
1 1
D13
0 1 1 0 1 1 1 0 1 0 1 0 GRAY CODE
BINARY 0
D11 D7 D3 D0 BIT POSITION
0 1
D13
BINARY 0 1 1 1 0 1 0 1 0 0 1 1 0 0
BINARY
X
= BINARY
X+1
GRAY
X
BINARY
12
= BINARY
13
GRAY
12
BINARY 12 = 0 1
BINARY 12 = 1
BINARY 11 = BINARY 12 GRAY 11
BINARY
11
= 1 0
BINARY 11 = 1
A B
0 0
0 1
1 0
1 1
0
1
1
0
EXCULSIVE OR TRUTH TABLE
Y = A B
Figure 9. Binary-to-Gray and Gray-to-Binary Code Conversion