Datasheet

AD7621
Rev. 0 | Page 6 of 32
Parameter Symbol Min Typ Max Unit
SLAVE SERIAL INTERFACE MODES
5
(Refer to Figure 40 and Figure 41)
External SCLK Setup Time t
31
5 ns
External SCLK Active Edge to SDOUT Delay t
32
1 8 ns
SDIN Setup Time t
33
5 ns
SDIN Hold Time t
34
5 ns
External SCLK Period t
35
12.5 ns
External SCLK High t
36
5 ns
External SCLK Low t
37
5 ns
1
See the Conversion Control section.
2
All timings for wideband warp mode are the same as warp mode.
3
In warp mode only, the time between conversions is 1 ms; otherwise, there is no required maximum time.
4
See the Digital Interface, and RESET sections.
5
In serial interface modes, the SYNC, SCLK, and SDOUT timings are defined with a maximum load C
L
of 10 pF; otherwise, the load is 60 pF maximum.
6
In serial master read during convert mode. See Table 4 for serial master read after convert mode timing specifications.
SERIAL CLOCK TIMING SPECIFICATIONS
Table 4. Serial Clock Timings in Master Read After Convert Mode
DIVSCLK[1] 0 0 1 1
DIVSCLK[0] Symbol 0 1 0 1 Unit
SYNC to SCLK First Edge Delay Minimum t
18
0.5 3 3 3 ns
Internal SCLK Period Minimum t
19
8 16 32 64 ns
Internal SCLK Period Maximum t
19
12 25 50 100 ns
Internal SCLK High Minimum t
20
2 6 15 31 ns
Internal SCLK Low Minimum t
21
3 7 16 32 ns
SDOUT Valid Setup Time Minimum t
22
1 5 5 5 ns
SDOUT Valid Hold Time Minimum t
23
0 0.5 10 28 ns
SCLK Last Edge to SYNC Delay Minimum t
24
0 0.5 9 26 ns
BUSY High Width Maximum (Wideband and Warp Modes) t
28
0.500 0.720 1.160 2.040 μs
BUSY High Width Maximum (Normal Mode) t
28
0.650 0.870 1.310 2.190 μs
BUSY High Width Maximum (Impulse Mode) t
28
0.780 1.000 1.440 2.320 μs
04565-002
NOTE
IN SERIAL INTERFACE MODES, THE SYNC, SCLK AND
SDOUT ARE DEFINED WITH A MAXIMUM LOAD.
C
L
OF 10pF; OTHERWISE, THE LOAD IS 60pF MAXIMUM.
500μAI
OL
500μAI
OH
1.4V
TO OUTPUT
PIN
C
L
50pF
Figure 2. Load Circuit for Digital Interface Timing,
SDOUT, SYNC, and SCLK Outputs, C
L
= 10 pF
0.8V
2V
2V
0.8V
0.8V
2V
t
DELAY
t
DELAY
05665-003
Figure 3. Voltage Reference Levels for Timing