DESCRIPTION
●The LOG114 is specifically designed for measuring low-level and wide dynamic range currents in communications, lasers, medical, and industrial systems. The device computes the logarithm or log-ratio of an input current or voltage relative to a reference current or voltage (logarithmic transimpedance amplifier).
●High precision is ensured over a wide dynamic range of input signals on either bipolar (±5V) or single (+5V) supply. Special temperature drift compensation circuitry is included on-chip. In log-ratio applications, the signal current may be from a high impedance source such as a photodiode or resistor in series with a low impedance voltage source. The reference current is provided by a resistor in series with a precision internal voltage reference, photo diode, or active current source.
●FEATURES
● ADVANTAGES:
● − Tiny for High Density Systems
● − Precision on One Supply
● − Fast Over Eight Decades
● − Fully-Tested Function
● TWO SCALING AMPLIFIERS
● WIDE INPUT DYNAMIC RANGE: Eight Decades, 100pA to 10mA
● 2.5V REFERENCE
● STABLE OVER TEMPERATURE
● LOW QUIESCENT CURRENT: 10mA
● DUAL OR SINGLE SUPPLY: ±5V, +5V
● PACKAGE: Small QFN-16 (4mm x 4mm)
● SPECIFIED TEMPERATURE RANGE: −5°C to +75°C
●APPLICATIONS
● ONET ERBIUM-DOPED FIBER OPTIC AMPLIFIER (EDFA)
● LASER OPTICAL DENSITY MEASUREMENT
● PHOTODIODE SIGNAL COMPRESSION AMP
● LOG, LOG-RATIO FUNCTION
● ANALOG SIGNAL COMPRESSION IN FRONT OF ANALOG-TO-DIGITAL (ADC) CONVERTER
● ABSORBANCE MEASUREMENT