Datasheet

AD676
REV. A
–4–
TIMING SPECIFICATIONS
Parameter Symbol Min Typ Max Units
Conversion Time
2
t
C
10 1000 µs
CLK Period
3
t
CLK
480 ns
Calibration Time t
CT
85,530 t
CLK
Sampling Time (Included in t
C
)t
S
2 µs
CAL to BUSY Delay t
CALB
75 150 ns
BUSY to SAMPLE Delay t
BS
2 µs
SAMPLE to BUSY Delay t
SB
15 100 ns
CLK HIGH
4
t
CH
50 ns
CLK LOW
4
t
CL
50 ns
SAMPLE LOW to 1st CLK Delay t
SC
50 ns
SAMPLE LOW t
SL
100 ns
Output Delay t
OD
125 200 ns
Status Delay t
SD
50 ns
CAL HIGH Time t
CALH
50 ns
NOTES
1
See the “CONVERSION CONTROL” and “AUTOCALIBRATION” sections for detailed explanations of the above timing.
2
Depends upon external clock frequency; includes acquisition time and conversion time. The maximum conversion time is specified to account for the droop of the
internal sample/hold function. Longer conversion times may degrade performance. See “General Conversion Guidelines” for additional explanation of maximum con-
version time.
3
580 ns is recommended for optimal accuracy over temperature.
4
t
CH
+ t
CL
= t
CLK
and must be greater than 480 ns.
CAL
BUSY
CLK
t
CH
t
CL
t
CLK
t
CALB
t
OD
t
CT
CALH
t
Figure 1. Calibration Timing
SAMPLE
(INPUT)
CLK
(INPUT)
BIT 1 – BIT 16
(OUTPUTS)
BUSY
(OUTPUT)
12345
t
S
t
SL
t
SC
t
CLK
t
CL
t
CH
t
OD
t
SD
t
SB
t
BS
t
C
13 14 15
16 17
(PREVIOUS CONVERSION)
(NEW DATA)
Figure 2a. General Conversion Timing
SAMPLE
(INPUT)
CLK
(INPUT)
BIT 1 – BIT 16
(OUTPUTS)
BUSY
(OUTPUT)
12345
t
S
t
SL
t
SC
t
CLK
t
CL
t
CH
t
OD
t
SD
t
SB
t
BS
t
C
13 14 15
16 17
t
S
(PREVIOUS CONVERSION)
(NEW DATA)
Figure 2b. Continuous Conversion Timing
(T
MIN
to T
MAX
V
CC
= +12 V 6 5%, V
EE
= –12 V 6 5%, V
DD
= +5 V 6 10%, V
REF
= 10.0 V)
1