AD7886
TIMING CHARACTERISTICS1
(VDD = +5 V ؎ 5%, VSS = –5 V ؎ 5%, AGND = DGND = 0 V)
Limit at
MIN, TMAX
Parameter (J, K Versions) (B Version) (T Version) Units Conditions/Comments
Limit at
TMIN, TMAX
Limit at
TMIN, TMAX
T
t1
50
1
50
1
50
1
ns min CONVST Pulse Width
Fs max
t2
t3
t4
t5
t63
t7
0
0
60
100
57
10
50
0
0
60
100
57
10
50
0
0
75
100
70
10
60
ns min CS to RD Setup Time
ns min CS to RD Hold Time
ns min RD Pulse Width
ns max CONVST to BUSY Propagation Delay, (CL = 10 pF)
ns max Data Access Time After RD
ns min Bus Relinquish Time After RD
ns max
t8
20
10
10
100
0
20
10
10
100
0
14
0
10
100
0
ns min Data Setup Time Prior to BUSY, (CL = 20 pF)
ns min Data Setup Time Prior to BUSY, (CL = 100 pF)
ns min Bus Relinquish Time After CONVST
ns max
ns min CS High to CONVST Low
ns min BUSY High to RD Low
3
t9
t10
t11
0
0
0
t12
t13
tCONV
250
1.333
950
1000
250
1.333
950
1000
250
1.333
950
1000
ns typ BUSY High to CONVST Low, SHA Acquisition Time
µs min Sampling Interval
ns typ Conversion Time
ns max
NOTES
1Timing 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.
2t6 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.
3t7 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, CL. This means that the times, t7 and t9, 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.
VIN1, VIN2, SUM, +5REF to AGND . . . . . . –15 V to +15 V
V
REF to AGND . . . . . . . . . . . . . . . . VSS –0.3 V to VDD +0.3 V
I
OL
Digital Inputs to DGND
CS, RD, CONVST . . . . . . . . . . . . . . –0.3 V to VDD +0.3 V
Digital Outputs to DGND
DB0 to DB11, BUSY . . . . . . . . . . . . . –0.3 V to VDD +0.3 V
Operating Temperature Range
TO OUTPUT
PIN
+2.1V
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
C
L
I
OH
NOTES
1Stresses 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.
Figure 1. Load Circuit for Bus Access and Relinquish Time
ABSOLUTE MAXIMUM RATINGS1, 2
(TA= +25°C unless otherwise noted)
2If VSS is open circuited with VDD and AGND applied, the VSS pin will be pulled
positive, exceeding the Absolute Maximum Ratings. If this possibility exists, a
Schottky diode from VSS to DGND (cathode end to GND) ensures that the
V
V
DD to AGND . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +7 V
SS to AGND . . . . . . . . . . . . . . . . . . . . . . . . . +0.3 V to –7 V
AGND to DGND . . . . . . . . . . . . . . . . . –0.3 V to VDD +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–
ADI [ ADI ]
