MAX1322ECM Maxim Integrated, MAX1322ECM Datasheet - Page 21

• Manufacturer Part Number: MAX1322ECM
• Description: Analog to Digital Converters - ADC
• Manufacturer: Maxim Integrated

Specifications of MAX1322ECM

• Number Of Channels: 2
• Architecture: SAR
• Conversion Rate: 526 KSPs
• Resolution: 14 bit
• Input Type: Single-Ended
• Snr: 76 dB
• Interface Type: Parallel
• Operating Supply Voltage: 2.7 V to 5.25 V, 4.75 V to 5.25 V
• Maximum Operating Temperature: + 85 C
• Package / Case: LQFP-48
• Maximum Power Dissipation: 1818 mW
• Minimum Operating Temperature: - 40 C
• Number Of Converters: 1
• Voltage Reference: 2.5 V

Figure 10. ±5V Bipolar Transfer Function
The input range is centered about V
MSV = AGND, and the input is symmetrical about zero.
For a custom midscale voltage, drive MSV with an
external voltage source. Noise present on MSV directly
couples into the ADC result. Use a precision, low-drift
voltage reference with adequate bypassing to prevent
MSV from degrading ADC performance. For maximum
FSR, be careful not to violate the absolute maximum
voltage ratings of the analog inputs when choosing
V
V
following equation:
Table 7 and Figure 11 show the offset binary transfer
function for the MAX1316/MAX1317/MAX1318 with a 0
to +5V input range. The FSR is two times the voltage at
REF. The internal +2.500V reference gives a +5V FSR,
while an external +2V to +3V reference allows an FSR
of +4V to +6V, respectively. Calculate the LSB size
using the following equation:
This equals 0.3052mV when using the internal reference.
8-/4-/2-Channel, 14-Bit, Simultaneous-Sampling ADCs
MSV
REF
, V
0x1FFD
0x1FFC
0x1FFF
0x1FFE
0x0001
0x0000
0x3FFF
0x2003
0x2002
0x2001
0x2000
. Determine the input voltage as a function of
with ±10V, ±5V, and 0 to +5V Analog Input Ranges
MSV
V
-8192 -8190
, and the output code in decimal using the
CH
_
=
______________________________________________________________________________________
LSB
INPUT VOLTAGE (V
LSB
=
×
2
CODE
-1 0 +1
Unipolar 0 to +5V Devices
4 x V
(MSV)
×
2
CH_
14
REF
V
- V
REF
10
MSV
1 LSB =
+
IN LSBs)
V
MSV
+8189
MSV
4 x V
. Normally,
2
14
+8191
REF
4 x V
REF
Table 6. ±5V Bipolar Code Table
Table 7. 0 to +5V Unipolar Code Table
BINARY OUTPUT CODE
BINARY OUTPUT CODE
TWO’S COMPLEMENT
11 1111 1111 1111
11 1111 1111 1110
10 0000 0000 0001
10 0000 0000 0000
01 1111 1111 1111
00 0000 0000 0001
00 0000 0000 0000
01 1111 1111 1111
01 1111 1111 1110
00 0000 0000 0001
00 0000 0000 0000
11 1111 1111 1111
10 0000 0000 0001
10 0000 0000 0000
0x3FFF
0x3FFE
0x2001
0x2000
0x1FFF
0x0001
0x0000
0x1FFE
0x1FFF
0x0001
0x0000
0x3FFF
0x2001
0x2000
EQUIVALENT
EQUIVALENT
DECIMAL
(CODE
OUTPUT
DECIMAL
(CODE
OUTPUT
16383
16382
8193
8192
8191
-8191
-8192
8191
8190
1
0
-1
1
0
10
10
)
)
(V
VOLTAGE (V)
VOLTAGE (V)
(V
REF
V
±0.5 LSB
±0.5 LSB
±0.5 LSB
±0.5 LSB
±0.5 LSB
±0.5 LSB
±0.5 LSB
REF
±0.5 LSB
±0.5 LSB
±0.5 LSB
±0.5 LSB
±0.5 LSB
±0.5 LSB
±0.5 LSB
MSV
= 2.5V)
INPUT
4.9998
4.9995
2.5005
2.5002
2.4998
0.0005
0.0002
-0.0003
-4.9991
-4.9997
INPUT
4.9997
4.9991
0.0009
0.0003
= V
= 2.5V,
= 0V)
REFMS
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