Datasheet

27Maxim Integrated
MAX11335–MAX11340
500ksps, 12-/10-Bit, 4-/8-/16-Channel ADCs with
Post-Mux External Signal Conditioning Access
Table 7. RANGE Register (RANGE Settings Only Applies to Bipolar Fully Differential
Analog Input Configurations)
ADC Output as a Function
of Unipolar and Bipolar Modes
The ADC Scan Control register (Table 3) determines the
ADC mode of operation. The Unipolar and Bipolar regis-
ters in Table 10 and Table 11 determine output coding
and whether input configuration is single-ended or fully
differential.
Table 9 details the conversion output for analog inputs,
AIN0 and AIN1. The truth table is consistent for any other
valid input pairs (AINn/AINn+1). Table 8 shows the appli-
cable input signal format with respect to analog input
configurations.
CHSEL[3:0] is used for MANUAL, REPEAT,
STANDARD_EXT, STANDARD_INT, UPPER_EXT,
UPPER_INT modes of operation. CHSCAN[15:0] is used
for
CUSTOM_EXT and CUSTOM_INT modes of operation.
SampleSet Mode of Operation
The SampleSet register stores the unique channel
sequence length. The sequence pattern is comprised of
up to 256 unique single-ended and/or differential conver-
sions with any order or pattern.
Patterns are assembled in 4-bit channel identifier nib-
bles as described in Table 4. Figure 10 presents the
SampleSet timing diagram. Note that two CS frames are
required to configure the SampleSet functionality. The
first frame indicates the sequence length. The second
frame is used to encode the channel sequence pattern.
After the SampleSet register has been coded (Table 14),
by the next falling edge of CS, the new SampleSet pattern
is activated (Figure 10). If the pattern length is less than
SEQ_LENGTH, the remaining channels default to AIN0. If
the select pattern length is greater than SEQ_LENGTH,
the additional data is ignored as the ADC waits for the ris-
ing edge of CS. If CS is asserted in the middle of a nibble,
the full nibble defaults to AIN0.
Upon receiving the SampleSet pattern, the user can
set the ADC Mode Control register to begin the conver-
sion process where data readout begins with the first
SampleSet entry. While the last conversion result is read,
the ADC can be instructed to enter AutoShutdown, if
desired. If the user wishes to change the SampleSet
length, a new pattern must be loaded into the ADC as
described in Figure 10.
BIT NAME BIT
DEFAULT
STATE
FUNCTION
RANGE_SETUP 15:11 N/A Set to 10011 to select the RANGE register
RANGE0/1 10 0
Set to 0 for AIN0/1: +V
REF+
/2, f
S
= V
REF+
- V
REF
-
Set to 1 for AIN0/1: +V
REF+
, f
S
= 2(V
REF+
- V
REF
-)
RANGE2/3 9 0
Set to 0 for AIN2/3: +V
REF+
/2, f
S
= V
REF+
- V
REF
-
Set to 1 for AIN2/3: +V
REF+
, f
S
= 2(V
REF+
- V
REF
-)
RANGE4/5 8 0
Set to 0 for AIN4/5: +V
REF+
/2, f
S
= V
REF+
- V
REF
-
Set to 1 for AIN4/5: +V
REF+
, f
S
= 2(V
REF+
- V
REF
-)
RANGE6/7 7 0
Set to 0 for AIN6/7: +V
REF+
/2, f
S
= V
REF+
- V
REF
-
Set to 1 for AIN6/7: +V
REF+
, f
S
= 2(V
REF+
- V
REF
-)
RANGE8/9 6 0
Set to 0 for AIN8/9: +V
REF+
/2, f
S
= V
REF+
- V
REF
-
Set to 1 for AIN8/9: +V
REF+
, f
S
= 2(V
REF+
- V
REF
-)
RANGE10/11 5 0
Set to 0 for AIN10/11: +V
REF+
/2, f
S
= V
REF+
- V
REF
-
Set to 1 for AIN10/11: +V
REF+
, f
S
= 2(V
REF+
- V
REF
-)
RANGE12/13 4 0
Set to 0 for AIN12/13: +V
REF+
/2, f
S
= V
REF+
- V
REF
-
Set to 1 for AIN12/13: +V
REF+
, f
S
= 2(V
REF+
- V
REF
-)
RANGE14/15 3 0
Set to 0 for AIN14/15: +V
REF+
/2, f
S
= V
REF+
- V
REF
-
Set to 1 for AIN14/15: +V
REF+
, f
S
= 2(V
REF+
- V
REF
-)
— 2:0 000 Unused