Datasheet

AD9218
Rev. C | Page 6 of 28
SWITCHING SPECIFICATIONS
V
DD
= 3.0 V, V = 3.0 V; external reference, unless otherwise noted.
D
Table 4.
Test AD9218BST-40/-65 AD9218BST-80/-105
Parameter Temp Level Min Typ Max Min Typ Max Unit
ENCODE INPUT PARAMETERS
Maximum Encode Rate Full VI 40/65 80/105 MSPS
Minimum Encode Rate Full IV 20/20 20/20 MSPS
Encode Pulse Width High (t
EH
) Full IV 7/6 5/3.8 ns
Encode Pulse Width Low (t
EL
) Full IV 7/6 5/3.8 ns
Aperture Delay (t
A
) 25°C V 2 2 ns
Aperture Uncertainty (Jitter) 25°C V 3 3 ps rms
DIGITAL OUTPUT PARAMETERS
Output Valid Time (t
V
) Full VI 2.5 2.5 ns
1
Output Propagation Delay (t
PD
)
1
Full VI 4.5 7 4.5 6 ns
Output Rise Time (t
R
) 25°C V 1 1.0 ns
Output Fall Time (t
F
) 25°C V 1.2 1.2 ns
Out-of-Range Recovery Time 25°C V 5 5 ns
Transient Response Time 25°C V 5 5 ns
Recovery Time from Power-Down 25°C V 10 10 Cycles
Pipeline Delay Full IV 5 5 Cycles
1
t and t
V PD
are measured from the 1.5 level of the ENCODE input to the 50%/50% levels of the digital outputs swing. The digital output load during test is not to exceed
an ac load of 5 pF or a dc current of ±40 μA. Rise and fall times are measured from 10% to 90%.
TIMING DIAGRAMS
02001-002
1/f
S
t
A
t
EH
t
EL
t
PD
t
V
SAMPLE N
ENCODE A
ENCODE B
D9
A
TO D0
A
D9
B
TO D0
B
A
IN
A
A
IN
B
DATA N – 5 DATA N – 4 DATA N – 3 DATA N – 2 DATA N – 1 DATA N
DATA N – 5 DATA N – 4 DATA N – 3 DATA N – 2 DATA N – 1 DATA N
SAMPLE
N + 1
SAMPLE
N + 5
SAMPLE
N + 6
SAMPLE
N + 2
SAMPLE
N + 3
SAMPLE
N + 4
Figure 2. Normal Operation, Same Clock (S1 = 1, S2 = 0) Channel Timing