MAX1270ACAI Maxim, MAX1270ACAI Datasheet - Page 10

• Manufacturer Part Number: MAX1270ACAI
• Description: Multirange / +5V / 8-Channel / Serial 12-Bit ADCs
• Manufacturer: Maxim

Range and Polarity
Multirange, +5V, 8-Channel,
Serial 12-Bit ADCs
Table 1. Control-Byte Format
Table 2. Channel Selection
Table 3. Range and Polarity Selection for MAX1270/MAX1271
7-178
Range and Polarity
RANGE AND POLARITY SELECTION FOR MAX1270
RANGE AND POLARITY SELECTION FOR MAX1271
INPUT RANGE
INPUT RANGE
1, 0 (LSB)
7 (MSB)
START
(MSB)
SEL2
6, 5, 4
Bit 7
0 to V
BIT
0 to V
0 to 10V
±V
0
0
0
0
1
1
1
1
0 to 5V
3
2
±V
±10V
±5V
___________________________________________________________________________________
REF
REF
REF
REF
/2
/2
SEL2, SEL1,
PD1, PD0
SEL1
START
NAME
SEL2
SEL0
Bit 6
RNG
BIP
0
0
1
1
0
0
1
1
RNG
RNG
0
1
0
1
0
1
0
1
First logic “1” after CS goes low defines the beginning of the control byte.
These three bits select the desired “on” channel (Table 2).
Selects the full-scale input voltage range (Table 3).
Selects unipolar or bipolar conversion mode (Table 3).
Select clock and power-down modes (Table 4).
SEL0
SEL1
Bit 5
0
1
0
1
0
1
0
1
CHANNEL
CH0
CH1
CH2
CH3
CH4
CH5
CH6
CH7
BIP
BIP
0
0
1
1
0
0
1
1
SEL0
Bit 4
NEGATIVE FULL
Table 4. Power Down and Clock Selection
-V
-V
FULL SCALE
NEGATIVE
Bit 3
RNG
REF
REF
PD1
SCALE
-V
0
0
1
1
-V
DESCRIPTION
REF
—
—
—
—
· 1.2207
· 2.4414
REF
/2
PD0
0
1
0
1
Bit 2
BIP
ZERO SCALE (V)
ZERO SCALE (V)
Normal Operation (always on),
Internal Clock Mode
Normal Operation (always on),
External Clock Mode
Standby Power-Down Mode (STBYPD),
Clock Mode Unaffected
Full Power-Down Mode (FULLPD),
Clock Mode Unaffected
0
0
0
0
0
0
0
0
Bit 1
PD1
MODE
FULL SCALE
FULL SCALE
V
V
V
V
REF
REF
REF
REF
V
V
V
V
REF
REF
· 1.2207
· 2.4414
· 1.2207
· 2.4414
REF
REF
(LSB)
Bit 0
PD0
/2
/2