AD8305 Analog Devices, AD8305 Datasheet - Page 5

• Manufacturer Part Number: AD8305
• Description: 100 Db-range (10nA-1mA) Logarithmic Converter
• Manufacturer: Analog Devices

REV. A
TPC 7. V
(Decade Steps from 10 nA to 1 mA)
TPC 8. Law Conformance Error vs. I
Supply Conditions (see Annotations)
–0.1
–0.2
–0.3
–0.4
–0.5
–0.1
–0.2
–0.3
–0.4
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.5
0.4
0.3
0.2
0.1
0.4
0.3
0.2
0.1
0
0
0
1n
1n
1n
10n
LOG
10n
10n
TPC 9. V
vs. I
100n
100n
100n
REF
+3V, 0V
+5V, 0V
+9V, 0V
+3V, –0.5V
+5V, –5V
10nA
for Multiple Values of I
INPT
1
100nA
1
1
I
REF
I
I
PD
PD
– V
1 A
– A
– A
– A
10
SUM
10 A
10
10
100 A
vs. I
100
100
1mA
100
PD
+12V, 0V
PD
for Various
1m
1m
1m
PD
10m
10m
10m
–5–
TPC 10. Law Conformance Error vs. I
Values of I
–0.1
–0.2
–0.3
–0.4
–0.5
TPC 12. Pulse Response – I
TPC 11. Pulse Response – I
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.5
0.4
0.3
0.2
0.1
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
0
0
–20
–20
1n
PD
0
100 A
0
10 A TO 100 A: T-RISE = 1 s,
T-FALL = < 1 s
10n
100nA TO 1 A: T-RISE = 30 s,
T-FALL = 5 s
(Decade Steps from 10 nA to 1 mA)
10nA TO 100nA: T-RISE = 30 s,
T-FALL = 20 s
100 A TO 1mA: T -RISE = < 1 s,
T-FALL = < 1 s
1 A TO 10 A: T-RISE = 5 s,
T-FALL = < 1 s
100 A TO 1mA: T-RISE = <1 s,
T-FALL = < 1 s
10 A TO 10 A: T-RISE = <1 s,
T-FALL = < 1 s
100nA TO 1 A: T-RISE = 5 s,
T-FALL = 20 s
T-FALL = 5 s
1 A TO 10 A: T-RISE = 1 s,
10nA TO 100nA: T -RISE = 20 s,
T-FALL = 30 s
20
20
10 A
1mA
100n
40
40
60
60
1
TIME – s
TIME – s
I
REF
80
80
– A
10nA
10
100
REF
100
PD
to V
to V
120
120
100nA
100
REF
OUT
OUT
for Multiple
140
140
AD8305
(G = 1)
(G = 1)
1m
160
1 A
160
10m
180
180