FEATURES

EASY-TO-USE COMPLETE FUNCTION

OUTPUT SCALING AMPLIFIER

ON-CHIP 2.5V VOLTAGE REFERENCE

HIGH ACCURACY: 0.2% FSO Over 5 Decades

WIDE INPUT DYNAMIC RANGE:

7.5 Decades, 100pA to 3.5mA

LOW QUIESCENT CURRENT: 1.75mA

WIDE SUPPLY RANGE: ±4.5V to ±18V

PACKAGES: SO-14 (narrow) and SO-16

APPLICATIONS

LOG, LOG RATIO:

Communication, Analytical, Medical, Industrial,

Test, General Instrumentation

PHOTODIODE SIGNAL COMPRESSION AMP

ANALOG SIGNAL COMPRESSION IN FRONT

OF ANALOG-TO-DIGITAL (A/D) CONVERTER

ABSORBANCE MEASUREMENT

OPTICAL DENSITY MEASUREMENT

DESCRIPTION

The LOG112 and LOG2112 are versatile integrated circuits

that compute the logarithm or log ratio of an input current

relative to a reference current. VLOGOUT of the LOG112 and

LOG2112 are trimmed to 0.5V per decade of input current,

ensuring high precision over a wide dynamic range of input

signals.

The LOG112 and LOG2112 features a 2.5V voltage reference

that may be used to generate a precision current

reference using an external resistor.

Low DC offset voltage and temperature drift allow accurate

measurement of low-level signals over the specified temperature

range of –5°C to +75°C.