AD674B/AD774B
DIGITAL SPECIFICATIONS
Parameter
(for all grades TMIN to TMAX with VCC = +15 V ؎ 10% or +12 V ؎ 5%, VLOGIC = +5 V ؎ 10%,
VEE = –15 V ؎ 10% or –12 V ؎ 5%)
Test Conditions
Min
Max
Units
LOGIC INPUTS
VIH
VIL
IIH
IIL
CIN
High Level Input Voltage
Low Level Input Voltage
High Level Input Current
Low Level Input Current
Input Capacitance
+2.0
–0.5
–10
VLOGIC +0.5 V
V
V
µA
µA
pF
+0.8
+10
+10
10
VIN = VLOGIC
VIN = 0 V
–10
LOGIC OUTPUTS
VOH
VOL
IOZ
High Level Output Voltage
IOH = 0.5 mA
IOL = 1.6 mA
VIN = 0 to VLOGIC
+2.4
–10
V
V
µA
pF
Low Level Output Voltage
High-Z Leakage Current
High-Z Output Capacitance
+0.4
+10
10
COZ
(for all grades TMIN to TMAX with VCC = +15 V ؎ 10% or +12 V ؎ 5%,
VLOGIC = +5 V ؎ 10%, VEE = –15 V ؎ 10% or –12 V ؎ 5%; unless otherwise noted)
SWITCHING SPECIFICATIONS
CONVERTER START TIMING (Figure 1)
tHEC
CE
__
tHSC
J, K, A, B Grades
Symbol Min Typ Max Min Typ Max Units
T Grade
CS
tSSC
tSRC
Parameter
_
R/C
tHRC
Conversion Time
8-Bit Cycle (AD674B) tC
12-Bit Cycle (AD674B) tC
8-Bit Cycle (AD774B) tC
12-Bit Cycle (AD774B) tC
6
9
4
6
8
10
6
9
4
6
8
10
µs
µs
µs
µs
12 15
5
7.3
12 15
5
7.3
A
tSAC
tHAC
0
6
8
6
8
STS Delay from CE
CE Pulse Width
CS to CE Setup
CS Low During CE High tHSC
R/C to CE Setup tSRC
R/C LOW During CE High tHRC
A0 to CE Setup tSAC
A0 Valid During CE High tHAC
tDSC
tHEC
tSSC
200
225 ns
STS
C
t
50
50
50
50
50
0
50
50
50
50
50
0
ns
ns
ns
ns
ns
ns
ns
tDSC
HIGH IMPEDANCE
DB11 – DB0
Figure 1. Convert Start Timing
50
50
CE
CS
t
SSR
t HSR
tHRR
_
R/C
READ TIMING—FULL CONTROL MODE (Figure 2)
J, K, A, B Grades T Grade
tSRR
tHAR
A
0
tSAR
Parameter
Symbol Min Typ Max Min Typ Max Units
STS
Access Time
CL = 100 pF
Data Valid After CE Low tHD
tHD
1
tDD
75 150
150
75 150 ns
HIGH
IMPEDANCE
DATA
VALID
HIGH
IMP.
DB11 – DB0
252
203
252
154
ns
ns
150 ns
tDD
tHL
5
Output Float Delay
CS to CE Setup
R/C to CE Setup
tHL
Figure 2. Read Cycle Timing
tSSR
tSRR
tSAR
tHSR
tHRR
tHAR
50
0
50
0
0
50
50
0
50
0
0
50
ns
ns
ns
ns
ns
ns
+5V
A0 to CE Setup
3k
CS Valid After CE Low
R/C High After CE Low
A0 Valid After CE Low
DB
N
DB
N
3k
100pF
100pF
NOTES
1tDD is measured with the load circuit of Figure 3a and is defined as the time required
for an output to cross 0.4 V or 2.4 V.
High-Z to Logic 1
High-Z to Logic 0
Figure 3a. Load Circuit for Access Time Test
20°C to TMAX
3At –40°C.
4At –55°C.
.
+5V
3k
5tHL is defined as the time required for the data lines to change 0.5 V when loaded with
the circuit of Figure 3b.
DB
N
DB
N
3k
Specifications shown in boldface are tested on all devices at final electrical test with
worst case supply voltages at TMIN, +25°C, and TMAX. Results from those tests are used
to calculate outgoing quality levels. All min and max specifications are guaranteed, al-
though only those shown in boldface are tested.
10pF
10pF
Logic 1 to High-Z
Figure 3b. Load Circuit for Output Float Delay Test
REV. B
Logic 0 to High-Z
Specifications subject to change without notice.
–4–