Datasheet

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SBOS301A − MAY 2004 − REVISED MARCH 2007
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6
ELECTRICAL CHARACTERISTICS: V
S
= +5V (continued)
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.
LOG114
PARAMETER UNITSMAXTYPMINCONDITIONS
TOTAL ERROR
(4, 5)
See Typical Characteristics
FREQUENCY RESPONSE, Core Log
(6)
BW, 3dB I
1
or I
2
= I
AC
= 10% of I
DC
value, I
REF
= 1µA
1nA 5 kHz
10nA 12 kHz
100nA 120 kHz
1µA 2.3 MHz
10µA to 1mA (ratio 1:100) > 5 MHz
1mA to 3.5mA (ratio 1:3.5) > 5 MHz
3.5mA to 10mA (ratio 1:2.9) > 5 MHz
Step Response I
REF
= 1µA
Increasing (I
1
or I
2
)
8nA to 240nA (ratio 1:30) 0.7 µs
10nA to 100nA (ratio 1:10) 1.5 µs
10nA to 1µA (ratio 1:100) 0.15 µs
10nA to 10µA (ratio 1:1k) 0.07 µs
10nA to 1mA (ratio 1:100k) 0.06 µs
1mA to 10mA (ratio 1:10) 1 µs
Decreasing (I
1
or I
2
) I
REF
= 1µA
8nA to 240nA (ratio 1:30) 1 µs
10nA to 100nA (ratio 1:10) 2 µs
10nA to 1µA (ratio 1:100) 0.25 µs
10nA to 10µA (ratio 1:1k) 0.05 µs
10nA to 1mA (ratio 1:100k) 0.03 µs
1mA to 10mA (ratio 1:10) 1 µs
VOLTAGE REFERENCE
Bandgap Voltage 2.5 V
Error, Initial ±0.15 ±1 %
vs Temperature ±25 ppm/°C
vs Supply V
S
= +4.8V to +11V ±30 ppm/V
vs Load I
O
= ±2mA ±200 ppm/mA
Short-Circuit Current ±10 mA
POWER SUPPLY
Single Supply Operating Range V
S
4.8 11 V
Quiescent Current I
Q
I
O
= 0 ±10 ±15 mA
TEMPERATURE RANGE
Specification, T
MIN
to T
MAX
−5 +75 °C
Operating −40 +85 °C
Storage −55 +125 °C
Thermal Resistance, q
JA
62 °C/W
(1)
Log conformity error is peak deviation from the best-fit straight line of V
O
vs Log (I
1
/I
2
) curve expressed as a percent of peak-to-peak full-scale output. Scale factor,
K, equals 0.375V output per decade of input current.
(2)
Scale factor of core log function is trimmed to 0.375V output per decade change of input current.
(3)
Specified by design.
(4)
Worst-case total error for any ratio of I
1
/I
2
, as the largest of the two errors, when I, and I
2
are considered separately.
(5)
Total error includes offset voltage, bias current, gain, and log conformity.
(6)
Small signal bandwidth (3dB) and transient response are a function of the level of input current. Smaller input current amplitude results in lower bandwidth.