
Dual, 65Msps, 14-Bit, IF/Baseband ADC
BINARY-TO-GRAY CODE CONVERSION
1)THE MOST SIGNIFICANT
D13 |
| D11 |
|
|
| D7 |
|
|
| D3 |
|
| D0 | BIT POSITION |
0 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | BINARY |
0 |
|
|
|
|
|
|
|
|
|
|
|
|
| GRAY CODE |
2)SUBSEQUENT
GRAYX = BINARYX + BINARYX + 1
WHERE + IS THE EXCLUSIVE OR FUNCTION (SEE TRUTH
TABLE BELOW) AND X IS THE BIT POSITION:
GRAY12 = BINARY12 + BINARY13
GRAY12 = 1 + 0
GRAY12 = 1
D13 |
| D11 | D7 | D3 | D0 | BIT POSITION |
0 | + 1 | 1 0 1 1 | 0 1 0 0 | 1 | 1 0 0 | BINARY |
0 | 1 |
|
|
|
| GRAY CODE |
3)REPEAT STEP 2 UNTIL COMPLETE: GRAY11 = BINARY11 + BINARY12 GRAY11 = 1 + 1
GRAY11 = 0
D13 |
|
|
| D11 |
| D7 |
|
|
| D3 |
|
| D0 | BIT POSITION | |
0 | 1 | + | 1 | 0 | 1 | 1 | 0 1 | 0 | 0 |
| 1 | 1 | 0 | 0 | BINARY |
0 | 1 |
| 0 |
|
|
|
|
|
|
|
|
|
|
| GRAY CODE |
4) THE FINAL |
|
|
|
|
|
| |||||||||
D13 |
| D11 |
|
|
| D7 |
|
|
| D3 |
|
| D0 | BIT POSITION | |
|
|
|
|
|
|
|
|
|
| ||||||
0 |
| 1 | 1 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | BINARY |
0 |
| 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 0 | GRAY CODE |
GRAY-TO-BINARY CODE CONVERSION
1)THE MOST SIGNIFICANT BINARY BIT IS THE SAME AS THE MOST SIGNIFICANT
D13 |
| D11 |
|
|
| D7 |
|
|
| D3 |
|
| D0 |
0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 0 |
0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
2)SUBSEQUENT BINARY BITS ARE FOUND ACCORDING TO THE FOLLOWING EQUATION:
BINARYX = BINARYX+1
WHERE + IS THE EXCLUSIVE OR FUNCTION (SEE TRUTH TABLE BELOW) AND X IS THE BIT POSITION:
BINARY12 = BINARY13 + GRAY12
BINARY12 = 0 + 1
BINARY12 = 1
D13 |
| D11 |
|
|
| D7 |
|
|
| D3 |
|
| D0 |
0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 0 |
| + |
|
|
|
|
|
|
|
|
|
|
|
|
01
3)REPEAT STEP 2 UNTIL COMPLETE:
BINARY11 = BINARY12 + GRAY11
BINARY11 = 1 + 0
BINARY11 = 1
D13 |
|
| D11 |
| D7 |
|
|
| D3 |
|
| D0 | |
0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 0 |
|
| + |
|
|
|
|
|
|
|
|
|
|
|
0 | 1 | 1 |
|
|
|
|
|
|
|
|
|
|
|
4) THE FINAL BINARY CONVERSION IS: |
|
|
|
|
|
| |||||||
D13 |
| D11 |
|
|
| D7 |
|
|
| D3 |
|
| D0 |
0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 0 |
0 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 |
BIT POSITION GRAY CODE
BINARY
BIT POSITION GRAY CODE
BINARY
BIT POSITION
GRAY CODE
BINARY
BIT POSITION GRAY CODE
BINARY
MAX12557
|
| EXCLUSIVE OR TRUTH TABLE | ||
FIGURE 8 SHOWS THE | A | B | Y = A + B | |
CODE CONVERSION IN OFFSET BINARY FORMAT. THE OUTPUT | ||||
|
|
| ||
FORMAT OF THE MAX12557 IS | 0 | 0 | 0 | |
HENCE EACH MSB OF THE | 0 | 1 | 1 | |
MUST BE INSERTED TO REFLECT TRUE OFFSET BINARY FORMAT. | ||||
1 | 0 | 1 | ||
| ||||
| 1 | 1 | 0 |
Figure 8. Binary-to-Gray and Gray-to-Binary Code Conversion
______________________________________________________________________________________ 21