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AD7273/AD7274
Rev. 0 | Page 7 of 28
TIMING SPECIFICATIONS
VDD = 2.35 V to 3.6 V; VREF = 2.35 to VDD; TA = TMIN to TMAX, unless otherwise noted.1 Guaranteed by characterization. All input signals are specified with tr = tf = 2 ns (10% to 90% of VDD) and timed from a voltage level of 1.6 V.
Table 4.
Parameter
Limit at TMIN, TMAX
AD7273/AD7274
Unit
Description
500
48
MHz max
tCONVERT
14 × tSCLK
AD7274
12 × tSCLK
AD7273
tQUIET
4
ns min
Minimum quiet time required between bus relinquish and start of
next conversion
t1
3
ns min
Minimum CS pulse width
t2
6
ns min
CS to SCLK setup time
4
ns max
Delay from CS until SDATA three-state disabled
15
ns max
Data access time after SCLK falling edge
t5
0.4 tSCLK
ns min
SCLK low pulse width
t6
0.4 tSCLK
ns min
SCLK high pulse width
t74
5
ns min
SCLK to data valid hold time
t8
14
ns max
SCLK falling edge to SDATA three-state
5
ns min
SCLK falling edge to SDATA three-state
t9
4.2
ns max
CS rising edge to SDATA three-state
1
μs max
Power-up time from full power-down
1 Sample tested during initial release to ensure compliance. All timing specifications given are with a 10 pF load capacitance. With a load capacitance greater than this
value, a digital buffer or latch must be used.
2 Mark/space ratio for the SCLK input is 40/60 to 60/40.
3 Minimum fSCLK at which specifications are guaranteed.
4 The time required for the output to cross the VIH or VIL voltage.
5 See the Power-Up Times section
SCLK
VIH
VIL
SDATA
t4
04973-002
Figure 2. Access Time After SCLK Falling Edge
SCLK
VIH
VIL
SDATA
t7
04973-003
Figure 3. Hold Time After SCLK Falling Edge
SCLK
1.4V
SDATA
t8
04973-004
Figure 4. SCLK Falling Edge SDATA Three-State