AD7886
TIMING CHARACTERISTICS
1
(V
Parameter
t
1
t
2
t
3
t
4
t
5
t
6
t
7 3
t
8
t
9 3
t
10
t
11
t
12
t
13
t
CONV
DD
= +5 V
5%, V
SS
= –5 V
5%, AGND = DGND = 0 V)
Limit at
Limit at
T
MIN
, T
MAX
T
MIN
, T
MAX
(J, K Versions) (B Version)
50
1
0
0
60
100
57
10
50
20
10
10
100
0
0
250
1.333
950
1000
50
1
0
0
60
100
57
10
50
20
10
10
100
0
0
250
1.333
950
1000
Limit at
T
MIN
, T
MAX
(T Version)
50
1
0
0
75
100
70
10
60
14
0
10
100
0
0
250
1.333
950
1000
Units
ns min
Fs max
ns min
ns min
ns min
ns max
ns max
ns min
ns max
ns min
ns min
ns min
ns max
ns min
ns min
ns typ
µs
min
ns typ
ns max
Conditions/Comments
CONVST
Pulse Width
CS
to
RD
Setup Time
CS
to
RD
Hold Time
RD
Pulse Width
CONVST
to
BUSY
Propagation Delay, (C
L
= 10 pF)
Data Access Time After
RD
Bus Relinquish Time After
RD
Data Setup Time Prior to
BUSY,
(C
L
= 20 pF)
Data Setup Time Prior to
BUSY,
(C
L
= 100 pF)
Bus Relinquish Time After
CONVST
CS
High to
CONVST
Low
BUSY
High to
RD
Low
BUSY
High to
CONVST
Low, SHA Acquisition Time
Sampling Interval
Conversion Time
NOTES
1
Timing specifications in
bold print
are 100% production tested. All other times are sample tested at +25°C to ensure compliance. All input signals are specified with tr =
tf = 5 ns (10% to 90% of 5 V) and timed from a voltage level of 1.6 V.
2
t
6
is measured with the load circuit of Figure 1 and defined as the time required for an output to cross 0.8 V or 2.4 V.
3
t
7
and t9 are derived from the measured time taken by the data outputs to change by 0.5 V when loaded with the circuit of Figure 1. The measured number is then extrapo-
lated back to remove the effects of charging or discharging the load capacitor, C
L
. This means that the times, t
7
and t
9
, quoted in the timing characteristics are the true bus
relinquish times of the part and as such are independent of external bus loading capacitances.
Specifications subject to change without notice.
I
OL
TO OUTPUT
PIN
+2.1V
C
L
I
OH
VIN1, VIN2, SUM, +5REF to AGND . . . . . . –15 V to +15 V
V
REF
to AGND . . . . . . . . . . . . . . . . V
SS
–0.3 V to V
DD
+0.3 V
Digital Inputs to DGND
CS, RD, CONVST . . . . . . . . . . . . . . –0.3 V to V
DD
+0.3 V
Digital Outputs to DGND
DB0 to DB11, BUSY . . . . . . . . . . . . . –0.3 V to V
DD
+0.3 V
Operating Temperature Range
Commercial (J, K Versions) . . . . . . . . . . . . . . 0°C to +70°C
Industrial (B Version) . . . . . . . . . . . . . . . . –40°C to +85°C
Extended (T Version) . . . . . . . . . . . . . . . –55°C to +125°C
Storage Temperature Range . . . . . . . . . . . .–65°C to + 150°C
Lead Temperature (Soldering, 10 secs) . . . . . . . . . . . . +300°C
Power Dissipation (Any Package) to +75°C . . . . . . 1000 mW
Derates above +75°C by . . . . . . . . . . . . . . . . . . . . 10 mW/°C
NOTES
1
Stresses above those listed under “Absolute Maximum Ratings” may cause
permanent damage to the device. This is a stress rating only; functional operation
of the device at these or any other conditions above those listed in the operational
sections of this specification is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability.
2
If V
SS
is open circuited with V
DD
and AGND applied, the V
SS
pin will be pulled
positive, exceeding the Absolute Maximum Ratings. If this possibility exists, a
Schottky diode from V
SS
to DGND (cathode end to GND) ensures that the
Figure 1. Load Circuit for Bus Access and Relinquish Time
ABSOLUTE MAXIMUM RATINGS
1, 2
(T
A
= +25°C unless otherwise noted)
V
DD
to AGND . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +7 V
V
SS
to AGND . . . . . . . . . . . . . . . . . . . . . . . . . +0.3 V to –7 V
AGND to DGND . . . . . . . . . . . . . . . . . –0.3 V to V
DD
+0.3 V
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the AD7886 features proprietary ESD protection circuitry, permanent damage may
occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD
precautions are recommended to avoid performance degradation or loss of functionality.
WARNING!
ESD SENSITIVE DEVICE
REV. B
–3–
AD [ ANALOG DEVICES ]
