LTC2440 Linear Technology, LTC2440 Datasheet - Page 14

• Manufacturer Part Number: LTC2440
• Description: 24-Bit High Speed Differential delta-sigma ADC
• Manufacturer: Linear Technology

APPLICATIO S I FOR ATIO
LTC2440
Table 4. LTC2440 Interface Timing Modes
Configuration
External SCK, Single Cycle Conversion
External SCK, 2-Wire I/O
Internal SCK, Single Cycle Conversion
Internal SCK, 2-Wire I/O, Continuous Conversion
14
BUSY
SDO
SCK
SDI
CS
U
*OSR4 BIT MUST BE AT FIRST SCK RISING EDGE DURING SERIAL DATA OUT CYCLE
Hi-Z
Table 3. SDI Speed/Resolution Programming
**Address allows tying SDI HIGH *Additional address to allow tying SDI LOW
OSR4 OSR3 OSR2 OSR1 OSR0 9MHz CLOCK 10.24MHz CLOCK NOISE ENOB
X
X
0
X
X
X
X
X
X
X
X
U
0
0
0
0
0
0
0
0
1
1
1
BIT 31
OSR4*
EOC
0
0
0
0
1
1
1
1
0
0
1
W
BIT 30
OSR3
Figure 4. SDI Speed/Resolution Programming
“0”
0
1
0
1
0
0
1
1
0
0
1
OSR2
BIT 29
SIG
1
0
0
1
0
1
0
1
0
1
1
External
External
Internal
Internal
Source
U
SCK
INTERNAL
BIT 28
OSR1
13.75Hz
6.875Hz
3.52kHz
1.76kHz
MSB
27.5Hz
880Hz
880Hz
440Hz
220Hz
110Hz
55Hz
CONVERSION RATE
BIT 27
OSR0
EXTERNAL
BIT 26
Conversion
CS and SCK
Continuous
15.625Hz
7.8125Hz
31.25Hz
62.5Hz
500Hz
250Hz
125Hz
Control
4kHz
2kHz
1kHz
1kHz
Cycle
CS ↓
SCK
BIT 25
750nV 22.9
510nV 23.4
375nV
250nV 24.4
200nV 24.6 32768**
3.5µV
1.4µV 21.8
23µV
RMS
2µV
2µV
1µV
BIT 1
21.3
21.3
22.4
CS and SCK
17
20
24
Control
Internal
Output
BIT 0
CS ↓
Data
LSB
SCK
16384
256*
1024
2048
4096
8192
OSR
128
256
512
64
2440 F04
Hi-Z
Connection
Waveforms
Figures 5, 6
Figures 8, 9
Figure 10
Figure 7
and
sn2440, 2440fas