LOG114 Datasheet, PDF (5/30 Pages) Burr-Brown (TI) – Single-Supply, High-Speed, Precision LOGARITHMIC AMPLIFIER

LOG114
www.ti.com
SBOS301A − MAY 2004 − REVISED MARCH 2007
ELECTRICAL CHARACTERISTICS: V_S = +5V
Boldface limits apply over the specified temperature range, T_A = −5°C to +75°C.
All specifications at T_A = +25°C, R_VLOGOUT = 10kΩ, V_CM = +2.5V, unless otherwise noted.
PARAMETER
CORE LOG FUNCTION
LOG CONFORMITY ERROR⁽¹⁾
Initial
Over Temperature
CONDITIONS
I_IN/V_OUT Equation
1nA to 100µA (5 decades)
100pA to 3.5mA (7.5 decades)
1mA to 10mA
1nA to 100µA (5 decades)
100pA to 3.5mA (7.5 decades)
1mA to 10mA
LOG114
MIN
TYP
MAX
V_O = (0.375V) Log (I₁/I₂) + V_CM
0.1
0.25
0.009
0.022
0.9
0.08
See Typical Characteristics
0.1
0.4
0.5
See Typical Characteristics
TRANSFER FUNCTION (GAIN)⁽²⁾
Initial Scaling Factor
Scaling Factor Error
Over Temperature
10nA to 100µA
1nA to 100µA
T_MIN to T_MAX
+15°C to +50°C
0.375
0.4
±2.5
0.0.35
0.21
0.035
±3.5
0.7
±3
INPUT, A₁ and A₂
Offset Voltage
vs Temperature
vs Power Supply
Input Bias Current
vs Temperature
Input Common-Mode Voltage Range
Voltage Noise
Current Noise
OUTPUT, A₃ (V_LOGOUT)
Output Offset, V_OSO, Initial
Over Temperature
Full Scale Output (FSO)⁽³⁾
Gain Bandwidth Product
Short-Circuit Current
Capacitive Load
V_OS
dV/dT
PSRR
I_B
V_CM
e_n
i_n
V_OSO
GBW
I_SC
T_MIN to T_MAX
V_S = +4.5V to +5.5V
T_MIN to T_MAX
f = 0.1Hz to 10kHz
f = 1kHz
f = 1kHz
T_MIN to T_MAX
V_S = +5V
I_IN = 1µA
±1
±7
+30
300
±5
Doubles every 10°C
(V−)+1.5 to
(V+)−1.5
3
30
4
±14
±65
±18
±80
(V−) + 0.6
(V+) − 0.6
50
±18
100
OP AMP, A₄ and A₅
Input Offset Voltage
vs Temperature
vs Supply
vs Common-Mode Voltage
Input Bias Current
Input Offset Current
Input Voltage Range
Input Noise f = 0.1Hz to 10Hz
f = 1kHz
Current Noise
Open-Loop Voltage Gain
Gain Bandwidth Product
Slew Rate
Settling Time 0.01%
Rated Output
Short-Circuit Current
V_OS
dV/dT
PSRR
CMRR
I_B
I_OS
T_MIN to T_MAX
V_S = +4.8V to +5.5V
i_n
A_OL
GBW
SR
t_S
I_SC
G = −1, 3V Step, C_L = 100pF
(V−)
(V−) + 0.5
±250
±2
30
70
−1
±0.05
1
28
2
100
15
5
1.5
+4/−10
±4000
(V+) − 1.5
(V+) − 0.5
UNITS
V
%
dB
%
dB
%
%
V/decade
%
dB
%
%
mV
µV/°C
µV/V
pA
V
µVrms
nV/√Hz
fA/√Hz
mV
mV
V
MHz
mA
pF
µV
µV/°C
µV/V
dB
µA
µA
V
µVPP
nV/√Hz
pA/√Hz
dB
MHz
V/µs
µs
V
mA
5