ltc2428 Linear Technology Corporation, ltc2428 Datasheet - Page 14

• Manufacturer Part Number: ltc2428
• Description: 4-/8-channel 20-bit ?power No Latency Delta-sigma Adc
• Manufacturer: Linear Technology Corporation

APPLICATIONS
LTC2424/LTC2428
As long as the voltage on the V
the – 0.3V to (V
range, a conversion result is generated for any input value
from – 0.125 • V
greater than 1.125 • V
to the value corresponding to 1.125 • V
voltages below – 0.125 • V
clamped to the value corresponding to – 0.125 • V
14
Table 2. LTC2424/LTC2428 Output Data Format
Input Voltage
V
9/8 • V
V
V
3/4V
3/4V
1/2V
1/2V
1/4V
1/4V
0
–1LSB
–1/8 • V
V
*The sign bit changes state during the 0 code.
IN
REF
REF
+
IN
/0
CSMUX/CSADC
> 9/8 • V
< –1/8 • V
–
REF
REF
REF
REF
REF
REF
+ 1LSB
REF
REF
SCK/CLK
+ 1LSB
+ 1LSB
+ 1LSB
SDO
REF
D
REF
IN
CC
REF
+ 0.3V) absolute maximum operating
EN
U
REF
to 1.125 • V
Bit 23
, the conversion result is clamped
EOC
D2
INFORMATION
0
0
0
0
0
0
0
0
0
0
0
0
0
0
U
REF
Hi-Z
D1
IN
, the conversion result is
Bit 22
DMY
pin is maintained within
REF
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
D0
. For input voltages
Figure 4. Typical Data Input/Output Timing
Bit 21
1/0*
SIG
1
1
1
1
1
1
1
1
1
1
0
0
0
REF
EOC
BIT 23
. For input
U
Bit 20
BIT 22
EXR
“0”
1
1
1
0
0
0
0
0
0
0
0
1
1
1
REF
.
SIG
Bit 19
MSB
0
0
0
1
1
1
1
0
0
0
0
1
1
1
EXT
Channel Selection
Typically, CSADC and CSMUX are tied together or CSADC
is inverted and drives CSMUX. SCK and CLK are tied
together and driven with a common clock signal. During
channel selection, CSMUX is HIGH. Data is shifted into the
D
shows the bit combinations for channel selection. In order
to enable the multiplexer output, CSMUX must be pulled
IN
Bit 18
pin on the rising edge of CLK, see Figure 4. Table 3
MSB
0
0
0
1
1
0
0
1
1
0
0
1
1
1
DON’T CARE
Bit 17
0
0
0
1
0
1
0
1
0
1
0
1
1
1
LSB
BIT 0
Bit 16
1
1
0
1
0
1
0
1
0
1
0
1
0
0
Bit 15
1
1
0
1
0
1
0
1
0
1
0
1
0
0
t
Hi-Z
CONV
…
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24248 F04
Bit 0
LSB
1
1
0
1
0
1
0
1
0
1
0
1
0
0