MAX1333 Maxim Integrated Products, MAX1333 Datasheet - Page 18

• Manufacturer Part Number: MAX1333
• Description: (MAX1332 / MAX1333) True-Differential 12-Bit ADCs
• Manufacturer: Maxim Integrated Products

Determine the differential analog input voltage as a
function of V
lowing equation:
where:
CODE
code (see Tables 1 and 2).
±0.5 x LSB represents the quantization error that is
inherent to any ADC.
When using a 4.096V reference, 1 LSB equals 1.0mV.
When using a 2.5V reference, 1 LSB equals 0.61mV.
3Msps/2Msps, 5V/3V, 2-Channel, True-
Differential 12-Bit ADCs
Table 1. Unipolar Code Table (MAX1332)
Table 2. Bipolar Code Table (MAX1332)
18
BINARY DIGITAL OUTPUT
DIGITAL OUTPUT CODE
TWO’s-COMPLEMENT
______________________________________________________________________________________
10
1111 1111 1111
1111 1111 1110
1000 0000 0001
1000 0000 0000
0111 1111 1111
0000 0000 0001
0000 0000 0000
0111 1111 1111
0111 1111 1110
0000 0000 0001
0000 0000 0000
1111 1111 1111
1000 0000 0001
1000 0000 0000
CODE D11–D0
= the decimal equivalent of the digital output
D11–D0
∆V
REF
AIN
∆V
and the digital output code with the fol-
LSB
AIN
=
LSB CODE
=
=
V
×
V
212
AIN P
REF
_
HEXADECIMAL EQUIVALENT
HEXADECIMAL EQUIVALENT
=
−
V
4096
10
V
REF
AIN N
±
0 5 .
OF D11–D0
OF D11–D0
_
0xFFF
0xFFE
0x801
0x800
0x7FF
0x001
0x000
×
0x7FF
0x7FE
0x001
0x000
0xFFF
0x801
0x800
LSB
DECIMAL EQUIVALENT OF
DECIMAL EQUIVALENT OF
The MAX1332/MAX1333 use an external reference
between 1V and (AV
a 1µF capacitor in parallel with a 0.1µF capacitor
to AGND for best performance (see the Typical
Operating Circuit).
The MAX1332/MAX1333 serial interface is fully compat-
ible with SPI, QSPI and MICROWIRE (see
a serial interface is available, set the µC’s serial inter-
face in master mode so the µC generates the serial
clock. Choose a clock frequency based on the AV
and DV
When using SPI or MICROWIRE, the MAX1332/
MAX1333 are compatible with all four modes pro-
grammed with the CPHA and CPOL bits in the SPI or
MICROWIRE control register. (This control register is in
D11–D0 (CODE
D11–D0 (CODE
DD
+2047
+2046
4095
4094
2049
2048
2047
-2047
-2048
+1
-1
1
0
0
Connection to Standard Interfaces
amplitudes.
Applications Information
10
10
)
)
DD
+ 50mV). Bypass REF with
VOLTAGE (V) (V
VOLTAGE (V) (V
SPI and MICROWIRE
DIFFERENTIAL INPUT
DIFFERENTIAL INPUT
External Reference
+4.095 ±0.5 LSB
+4.094 ±0.5 LSB
+2.049 ±0.5 LSB
+2.048 ±0.5 LSB
+2.047 ±0.5 LSB
+0.001 ±0.5 LSB
+0.000 ±0.5 LSB
+0.001 ±0.5 LSB
+2.047 ±0.5 LSB
+2.046 ±0.5 LSB
-0.001 ±0.5 LSB
-2.047 ±0.5 LSB
-2.048 ±0.5 LSB
0.000 ±0.5 LSB
REF
REF
Figure 11). If
= 4.096V )
= 4.096V)
DD