Datasheet

MAX4207
Precision Transimpedance Logarithmic
Amplifier with Over 5 Decades of Dynamic Range
_______________________________________________________________________________________ 7
Typical Operating Characteristics (continued)
(V
CC
= +5V, V
EE
= -5V, GND = 0V, I
REF
= 1µA, I
LOG
= 10µA, LOGV2 = SCALE, LOGV1 = OSADJ, CMVIN = CMVOUT, R
SET
> 1MΩ,
T
A
= +25°C, unless otherwise noted.)
REFERENCE OUTPUT VOLTAGE (V
REFVOUT
)
vs. SUPPLY VOLTAGE (V
CC
- V
EE
)
MAX4207 toc23
SUPPLY VOLTAGE (V)
REFERENCE OUTPUT VOLTAGE (V)
109876
1.205
1.210
1.215
1.220
1.225
1.230
1.235
1.240
1.245
1.250
1.200
511
0
-100
10 100 1k 10k 100k 1M
REFERENCE POWER-SUPPLY REJECTION
RATIO vs. FREQUENCY
-80
MAX4207 toc24
FREQUENCY (Hz)
REFERENCE PSRR (dB)
-60
-40
-20
-90
-70
-50
-30
-10
C
REFVOUT
= 0.1µF
I
REFVOUT
= 1mA
REFERENCE LINE-TRANSIENT RESPONSE
MAX4207 toc25
10
µ
s/div
0V
V
CC
- V
EE
5V/div
V
REFVOUT
200mV/div
1.238V
C
REFVOUT
= 0F
REFERENCE LOAD-TRANSIENT RESPONSE
MAX4207 toc26
100
µ
s/div
0mAI
REFVOUT
1mA/div
V
REFVOUT
100mV/div
1.24V
C
REFVOUT
= 0F
SMALL-SIGNAL AC RESPONSE
(I
LOG
TO V
LOGV1
)
MAX4207 toc29
FREQUENCY (Hz)
NORMALIZED GAIN (dB)
1M100k10k1k
-50
-40
-30
-20
-10
0
10
-60
100 10M
I
LOG
= 100
µ
A
I
LOG
= 1mA
I
LOG
= 10
µ
A
I
LOG
= 1
µ
A
I
LOG
= 100nA
C
COMP
= 100pF
R
COMP
= 100Ω
I
REF
= 10µA
SMALL-SIGNAL AC RESPONSE
OF BUFFER
MAX4207 toc30
FREQUENCY (Hz)
NORMALIZED GAIN (dB)
10M1M100k
-9
-6
-3
0
3
-12
10k 100M
A
V
= 2V/V
A
V
= 4V/V
A
V
= 1V/V
REFERENCE TURN-ON TRANSIENT RESPONSE
MAX4207 toc27
10µs/div
0V
V
CC
- V
EE
5V/div
V
REFVOUT
500mV/div
0V
C
REFVOUT
= 0F
SMALL-SIGNAL AC RESPONSE
(I
LOG
TO V
LOGV1
)
MAX4207 toc28
FREQUENCY (Hz)
NORMALIZED GAIN (dB)
1M100k10k1k
-50
-40
-30
-20
-10
0
10
-60
100 10M
I
LOG
= 100µA
I
LOG
= 1mA
I
LOG
= 10µA
C
COMP
= 33pF
R
COMP
= 330Ω
I
REF
= 10µA
I
LOG
= 1µA
I
LOG
= 100nA