LTC1417 LINER [Linear Technology], LTC1417 Datasheet - Page 20

• Manufacturer Part Number: LTC1417
• Description: Low Power 14-Bit, 400ksps Sampling ADC Converter with Serial I/O
• Manufacturer: LINER [Linear Technology]

APPLICATIONS
LTC1417
Using External Clock for Conversion and Data Transfer.
In Figure 18, data from the previous conversion is output
during the conversion with an external clock providing
both the conversion clock and the shift clock. To select an
external conversion clock, apply the clock to EXTCLKIN.
The same clock is also applied to SCLK to provide a data
EXTCLKIN (= SCLK)
20
BUSY (= RD)
CONVST
D
OUT
(SAMPLE N)
t
dEXTCLKIN
Hi-Z
t
3
t
7
U
Figure 18. External Conversion Clock Selected. Data Transferred During Conversion Using
the External Clock (External Clock Drives Both EXTCLKIN and SCLK)
D13
1
t
2
INFORMATION
U
D12
2
D11
3
EXTCLKIN
(= SCLK)
CONVST
D
D10
W
OUT
4
D9
13
5
V
D13
IL
CONVST
D8
t
6
t
12
LEXTCLKIN
t
U
11
LTC1417
DATA (N – 1)
EXTCLKIN
D7
RISING CLOCK
7
CAPTURE ON
t
CONV
BUSY
SCLK
D
OUT
RD
D6
8
14
9
t
HEXTCLKIN
HOLD
12
6
7
D12
D5
9
FALLING CLOCK
shift clock. To maintain conversion accuracy, the external
clock frequency must be between 50kHz and 9MHz.
Using an external clock to transfer data while an internal
clock controls the conversion process is not recom-
mended. As both signals are asynchronous, clock noise
can corrupt the conversion result.
EXTCLKIN ( = SCLK)
t
10
CAPTURE ON
BUSY (= RD)
D4
10
D
OUT
D3
11
D2
D11
12
V
V
P OR DSP
OH
OL
D1
13
D0
14
15
ZEROS
FILL
16
t
D13
4
(SAMPLE N + 1)
SAMPLE
t
5
Hi-Z
t
8
D13
1
DATA N
HOLD
D12
2
D11
1417 F18
3