(V = +5 V, T = +25 C, unless otherwise noted)
S
A
Parameter
INPUT STAGE
Maximum Input
2
Equivalent Power in 50
Ω
Noise Floor
Equivalent Power in 50
Ω
Input Resistance
Input Capacitance
DC Bias Voltage
LIMITING AMPLIFIER
Usable Frequency Range
At Limiter Output
Phase Variation at 100 MHz
Limiter Output Current
Input Range
3
Maximum Output Voltage
Rise/Fall Time (10%–90%)
LOGARITHMIC AMPLIFIER
±
3 dB Error Dynamic Range
Transfer Slope
Intercept (Log Offset)
Conditions
(Inputs INHI, INLO)
Differential Drive, p-p
Terminated in 52.3
Ω
Terminated 50
Ω
Source
500 MHz Bandwidth
From INHI to INLO
From INHI to INLO
Either Input
(Outputs LMHI, LMLO)
R
LOAD
= R
LIM
= 50
Ω
to –10 dB Point
Over Input Range –60 dBm to +10 dBm
Nominally 400 mV/R
LIM
Versus Temperature –40°C
≤
T
A
≤
+85°C
Equivalent dBm
At Either LMHI or LMLO, wrt VPS2
R
LOAD
≤
50
Ω,
40
Ω ≤
R
LIM
≤
400
Ω
(Output VLOG)
From Noise Floor to Maximum Input
5 MHz
≤
f
≤
200 MHz
Over Temperature –40°C < T
A
< +85°C
5 MHz
≤
f
≤
200 MHz
Equivalent dBm (re 50
Ω)
Over Temperature –40°C
≤
T
A
≤
+85°C
Equivalent dBm (re 50
Ω)
Temperature Sensitivity
Input from –83 dBV (–70 dBm) to +7 dBV (+20 dBm)
Input = –91 dBV (–78 dBm) V
S
= +5 V, +2.7 V
Input = +9 dBV (+22 dBm) V
S
= +5 V
Input = +9 dBV (+22 dBm) V
S
= +2.75 V
To Ground
Min
1
±
3.5
Typ
±
4
+9
+22
1.28
–78
1000
2.5
1.725
Max
1
Units
V
dBV
dBm
nV/√Hz
dBm
Ω
pF
V
MHz
MHz
Degrees
mA
%/°C
dBV
dBm
V
ns
dB
mV/dB
mV/dB
dBV
dBm
dBV
dBm
dB/°C
dB
V
V
V
Ω
mA
Ω
MHz
ns
ns
V
mA
mA
µA
mA
V
µA
V
800
1200
5
875
±
3
1
–0.008
500
0
–78
–65
1
10
+9
+22
1.25
0.4
100
20
20
–108
–95
–108
–95
–0.009
±
0.4
0.34
2.34
2.10
50
1.0
0.3
3.5
120
67
18
17
–116
–103
–117
–104
22
23
–100
–87
–99
–86
Linearity Error (Ripple)
Output Voltage
2.75
Minimum Load Resistance, R
L
Maximum Sink Current
Output Resistance
Small-Signal Bandwidth
Output Settling Time to 1%
Rise/Fall Time (10%–90%)
POWER INTERFACES
Supply Voltage, V
POS
Quiescent Current
Over Temperature
Disable Current
Additional Bias for Limiter
Logic Level to Enable Power
Input Current when HI
Logic Level to Disable Power
40
0.75
1.25
Large Scale Input, +3 dBV (+16 dBm),
R
L
≥
50
Ω,
C
L
≤
100 pF
Large Scale Input, +3 dBV (+16 dBm),
R
L
≥
50
Ω,
C
L
≤
100 pF
2.7
13
11
220
100
6.5
20
23
4
1.6
V
POS
60
1
Zero-Signal, LMDR Open
–40°C < T
A
< +85°C
–40°C < T
A
< +85°C
R
LIM
= 400
Ω
(See Text)
HI Condition, –40°C < T
A
< +85°C
3 V at ENBL, –40°C < T
A
< +85°C
LO Condition, –40°C < T
A
< +85°C
5
16
16
0.01
1.4
40
1.8
–0.5
NOTES
1
Minimum and maximum specified limits on parameters that are guaranteed but not tested are six sigma values.
2
The input level is specified in “dBV” since logarithmic amplifiers respond strictly to voltage, not power. 0 dBV corresponds to a sinusoidal single-frequency input of
1 V rms. A power level of 0 dBm (1 mW) in a 50
Ω
termination corresponds to an input of 0.2236 V rms. Hence, the relationship between dBV and dBm is a fixed
offset of +13 dBm in the special case of a 50
Ω
termination.
3
Due to the extremely high Gain Bandwidth Product of the AD8309, the output of either LMHI or LMLO will be unstable for levels below –78 dBV (–65 dBm, re 50
Ω).
Specifications subject to change without notice.
–2–
REV. B
AD [ ANALOG DEVICES ]
