AD8305 Analog Devices, AD8305 Datasheet - Page 2

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

AD8305–SPECIFICATIONS
Parameter
INPUT INTERFACE
LOGARITHMIC OUTPUT
REFERENCE OUTPUT
OUTPUT BUFFER
POWER SUPPLY
NOTES
1
2
Other values of logarithmic intercept can be achieved by adjusting R
Output noise and incremental bandwidth are functions of input current, measured using output buffer connected for GAIN = 1.
Specified Current Range, I
Input Current Min/Max Limits
Reference Current, I
Summing Node Voltage
Temperature Drift
Input Offset Voltage
Logarithmic Slope
Logarithmic Intercept
Law Conformance Error
Wideband Noise
Small Signal Bandwidth
Maximum Output Voltage
Minimum Output Voltage
Output Resistance
Voltage wrt Ground
Maximum Output Current
Incremental Output Resistance
Input Offset Voltage
Input Bias Current
Incremental Input Resistance
Output Range
Incremental Output Resistance
Peak Source/Sink Current
Small Signal Bandwidth
Slew Rate
Positive Supply Voltage
Quiescent Current
Negative Supply Voltage (Optional)
2
REF
1
, Range
2
PD
Conditions
Pin 4, INPT, Pin 3, IREF
Flows toward INPT Pin
Flows toward INPT Pin
Flows toward IREF Pin
Internally Preset; May be Altered by User
–40∞C < T
V
Pin 9, VLOG
–40∞C < T
–40∞C < T
10 nA < I
I
I
Limited by V
Pin 2, VREF
–40∞C < T
Sourcing (Grounded Load)
Load Current < 10 mA
Pin 10, BFIN; Pin 11, SCAL; Pin 12, VOUT
Flowing out of Pin 10 or 11
R
Load Current < 10 mA
GAIN = 1
0.2 V to 4.8 V Output Swing
Pin 8, VPOS; Pin 6 and Pin 7, VNEG
(V
(V
PD
PD
INPT
L
P
P
= 1 kW to ground
> 1 mA
> 1 mA
– V
– V
– V
N
N
) £ 12 V
) £ 12 V
SUM
PD
A
A
A
A
< +85∞C
< +85∞C
< +85∞C
< 1 mA
< +85∞C
N
, V
(V
otherwise noted.)
= 0 V
P
REF
IREF
= 5 V, V
.
– V
SUM
N
–2–
= 0 V, T
A
= 25 C, R
REF
= 200 k , and VRDZ connected to VREF, unless
Min
10 n
10 n
0.46
–20
190
185
0.3
0.1
4.375
2.435
2.4
–20
3
–5.5
Typ
0.5
0.015
200
1
0.1
0.7
0.7
1.7
0.01
5
2.5
20
2
0.4
35
V
0.5
25
15
15
5
5.4
0
P
– 0.1
Max
1 m
10 m
1 m
+20
210
215
1.7
2.5
0.4
5.625
2.565
+20
12
6.5
0.54
2.6
Unit
A
A
A
V
mV/∞C
mV
mV/dec
mV/dec
nA
nA
dB
mV÷Hz
MHz
V
V
kW
V
V
mA
W
mV
mA
MW
V
W
mA
MHz
V/ms
V
mA
V
REV. A