
LTC2411/LTC2411-1
18
Figure 7. External Serial Clock, CS = 0 Operation
EOC
BIT 31
SDO
SCK
(EXTERNAL)
CS
MSB
SIG
BIT 0
LSB24
BIT 5
BIT 27
BIT 26
BIT 28
BIT 29
BIT 30
SLEEP
DATA OUTPUT
CONVERSION
2411 F07
CONVERSION
VCC
FO
REF+
REF–
SCK
IN+
IN–
SDO
GND
CS
110
2
3
9
4
5
8
6
7
REFERENCE
VOLTAGE
0.1V TO VCC
ANALOG INPUT RANGE
–0.5VREF TO 0.5VREF
2-WIRE I/O
1
F
2.7V TO 5.5V
= 50Hz REJECTION (LTC2411)
= EXTERNAL OSCILLATOR
= 60Hz REJECTION (LTC2411)
= SIMULTANEOUS 50Hz/60Hz REJECTION (LTC2411-1)
VCC
LTC2411/
LTC2411-1
Figure 8. Internal Serial Clock, Single Cycle Operation
Data is shifted out the SDO pin on each falling edge of SCK
enabling external circuitry to latch data on the rising edge
of SCK. EOC can be latched on the first rising edge of SCK.
On the 32nd falling edge of SCK, SDO goes HIGH (EOC = 1)
indicating a new conversion has begun.
Internal Serial Clock, Single Cycle Operation
This timing mode uses an internal serial clock to shift out
the conversion result and a CS signal to monitor and
control the state of the conversion cycle, see Figure 8.
SDO
SCK
(INTERNAL)
CS
MSB
SIG
BIT 0
LSB24
BIT 5
TEST EOC
BIT 27
BIT 26
BIT 28
BIT 29
BIT 30
EOC
BIT 31
SLEEP
DATA OUTPUT
CONVERSION
2411 F08
<tEOCtest
VCC
10k
Hi-Z
TEST EOC
VCC
FO
REF+
REF–
SCK
IN+
IN–
SDO
GND
CS
110
2
3
9
4
5
8
6
7
REFERENCE
VOLTAGE
0.1V TO VCC
ANALOG INPUT RANGE
–0.5VREF TO 0.5VREF
3-WIRE
SPI INTERFACE
1
F
2.7V TO 5.5V
= 50Hz REJECTION (LTC2411)
= EXTERNAL OSCILLATOR
= 60Hz REJECTION (LTC2411)
= SIMULTANEOUS 50Hz/60Hz REJECTION (LTC2411-1)
VCC
LTC2411/
LTC2411-1
APPLICATIO S I FOR ATIO
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