Datasheet

ADS1255
ADS1256
SBAS288K − JUNE 2003 − REVISED SEPTEMBER 2013
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7
SCLK
t
13
t
12
t
13
t
15
t
14
Figure 2. SCLK Reset Timing
TIMING CHARACTERISTICS FOR FIGURE 2
SYMBOL DESCRIPTION MIN MAX UNIT
t
12
SCLK reset pattern, first high pulse
300 500 τ
CLKIN
(1)
t
13
SCLK reset pattern, low pulse
5 τ
CLKIN
t
14
SCLK reset pattern, second high pulse
550 750 τ
CLKIN
t
15
SCLK reset pattern, third high pulse
1050 1250 τ
CLKIN
(1)
τ
CLKIN
= master clock period = 1/f
CLKIN
.
t
16
RESET, SYNC/PDWN
CLKIN
t
16B
SYNC/PDWN
Figure 3. RESET and SYNC/PDWN Timing
TIMING CHARACTERISTICS FOR FIGURE 3
SYMBOL DESCRIPTION MIN MAX UNIT
t
16
RESET, SYNC/PDWN, pulse width
4 τ
CLKIN
(1)
t
16B
SYNC/PDWN rising edge to CLKIN rising edge
−25 25 ns
(1)
τ
CLKIN
= master clock period = 1/f
CLKIN
.
DRDY
t
17
Figure 4. DRDY Update Timing
TIMING CHARACTERISTICS FOR FIGURE 4
SYMBOL DESCRIPTION MIN MAX UNIT
t
17
Conversion data invalid while being updated (DRDY shown with no data retrieval)
16 τ
CLKIN
(1)
(1)
τ
CLKIN
= master clock period = 1/f
CLKIN
.