MAX1434_11 Datasheet, PDF (16/22 Pages) Maxim Integrated Products – Octal, 12-Bit, 50Msps, 1.8V ADC with Serial LVDS Outputs

Octal, 10-Bit, 50Msps, 1.8V ADC
with Serial LVDS Outputs
Table 2. Output Code Table (V_REFIO = 1.24V)
TWO’S-COMPLEMENT DIGITAL OUTPUT CODE
(T/B = 0)
BINARY
D9 → D0
HEXADECIMAL DECIMAL
EQUIVALENT EQUIVALENT
OF D9 → D0 OF D9 → D0
OFFSET BINARY DIGITAL OUTPUT CODE
(T/B = 1)
BINARY
D9 → D0
HEXADECIMAL DECIMAL
EQUIVALENT EQUIVALENT
OF D9 → D0 OF D9 → D0
V_IN__P - V_IN__N (mV)
(V_REFIO = 1.24V)
0111111111
0111111110
0x1FF
0x1FE
+511
+510
1111111111
1111111110
0x3FF
0x3FE
+1023
+1022
+698.63
+697.27
0000000001
0000000000
1111111111
0x001
0x000
0x3FF
+1
1000000001
0x201
0
1000000000
0x200
-1
0111111111
0x1FF
+513
+512
+511
+1.37
0
-1.37
1000000001
0x201
-511
0000000001
0x001
+1
1000000000
0x200
-512
0000000000
0x000
0
-698.63
-700.00
1 LSB =2 ^{x FSR}
1024
FSR
0x1FF
0x1FE
0x1FD
FSR = 700mV xVREFIO
1.24V
FSR
1 LSB =2 ^{x FSR}
1024
FSR
0x3FF
0x3FE
0x3FD
FSR = 700mV xVREFIO
1.24V
FSR
0x001
0x000
0x3FF
0x201
0x200
0x1FF
0x203
0x202
0x201
0x200
-511 -509
-1 0 +1
+509 +511
DIFFERENTIAL INPUT VOLTAGE (LSB)
Figure 6. Two’s-Complement Transfer Function (T/B = 0)
Output Data Format (T/B) Transfer Functions
The MAX1434 output data format is either offset binary
or two’s complement, depending on the logic-input T/B.
With T/B low, the output data format is two’s comple-
ment. With T/B high, the output data format is offset
binary. The following equations, Table 2, and Figures 6
and 7 define the relationship between the digital output
and the analog input. For two’s complement (T/B = 0):
V_{IN_P}
−
V_{IN_N}
=
FSR
×
2
×
CODE₁₀
1024
0x003
0x002
0x001
0x000
-511 -509
-1 0 +1
+509 +511
DIFFERENTIAL INPUT VOLTAGE (LSB)
Figure 7. Binary Transfer Function (T/B = 1)
and for offset binary (T/B = 1):
V_{IN_P}
−
V_{IN_N}
=
FSR
×
2
×
CODE₁₀ −
1024
512
where CODE₁₀ is the decimal equivalent of the digital
output code as shown in Table 2.
Keep the capacitive load on the MAX1434 digital out-
puts as low as possible.
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