5.5 Electrical Characteristics (±5V) (continued)

All specifications at TA = 25°C, VS = ±5V, VLOGOUT RL = 10kΩ, VCM = GND, unless otherwise noted.

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

AOL

Open-loop voltage gain

100

dB

GBW

Gain-bandwidth product

15

MHz

SR

Slew rate

5

V/μs

tS

Settling time 0.01%

G = -1, 3V step, CL = 100pF

1.5

µs

Rated output

(V–) + 0.5V

(V+) – 0.5V

V

ISC

Short-circuit current

Sourcing

+4

mA

Sinking

–10

mA

TOTAL ERROR

Total error(4) (5)

See typical characteristics

FREQUENCY RESPONSE, Core Log

BW, 3 dB, I1 or I2 (6)

IAC = 10% of IDC value,

IREF = 1µA

1nA

5

kHz

10nA

12

100nA

120

1µA

2.3

MHz

10µA to 10mA

> 5

Step response, I1 or I2 (6)

8nA to 240nA (ratio 1:30)

Increasing, IREF = 1µA

0.8

µs

Decreasing, IREF = 1µA

6

10nA to 100nA (ratio 1:10)

Increasing, IREF = 1µA

1.5

Decreasing, IREF = 1µA

5

10nA to 1µA (ratio 1:100)

Increasing, IREF = 1µA

0.25

Decreasing, IREF = 1µA

4

1mA to 10mA (ratio 1:10)

Increasing, IREF = 1µA

1

Decreasing, IREF = 1µA

1

VOLTAGE REFERENCE

Bandgap voltage

2.5

V

Error

±0.15

±1

%

TA = -5℃ to 75℃

±25

ppm/

℃

VS = ±4.5V to ±5.5V

±30

ppm/V

IO = ±2mA

±200

ppm/mA

Short-circuit current

±10

mA

POWER SUPPLY

IQ

Quiescent current

IO = 0

±10

±15

mA

(1)

Log conformity error is peak deviation from the best-fit straight line of VO vs Log (I1/I2) 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 I1/I2, as the largest of the two errors, when I, and I2 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.

LOG114

SBOS301B – MAY 2004 – REVISED MARCH 2025

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