Overview
The LOG114AIRGVT from Texas Instruments is a precision high-speed logarithmic amplifier designed for measuring low-level and wide dynamic range currents in various systems, including communications, lasers, medical, and industrial applications. This device computes the logarithm or log-ratio of an input current or voltage relative to a reference current or voltage, ensuring high precision over a wide dynamic range of input signals. It operates on either bipolar (±5V) or single (+5V) supply and includes special temperature drift compensation circuitry for stable performance over a wide temperature range.
Key Specifications
| Parameter | Value | Units |
|---|---|---|
| Package | VQFN-16 (RGV) | - |
| Pins | 16 | - |
| Operating Temperature Range | -5°C to +75°C | °C |
| Input Dynamic Range | 100pA to 10mA (Eight Decades) | - |
| Reference Voltage | 2.5V | V |
| Quiescent Current | ±10mA | mA |
| Supply Voltage | ±2.4V to ±5.5V (Dual), 4.8V to 11V (Single) | V |
| Output Scale Factor | 0.375V per decade of input current | V/decade |
| Frequency Response (3dB) | Up to 2.3 MHz | Hz |
| Thermal Resistance (θJA) | 62°C/W | °C/W |
Key Features
- Tiny for High Density Systems: Small QFN-16 package (4mm x 4mm)
- Precision on One Supply: High precision over a wide dynamic range on either bipolar or single supply
- Fast Over Eight Decades: Wide input dynamic range from 100pA to 10mA
- Two Scaling Amplifiers: Allows for scaling and offsetting the output signal
- Stable Over Temperature: Special temperature drift compensation circuitry included
- Low Quiescent Current: ±10mA
- Dual or Single Supply: Operates on ±5V or +5V supply
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
Q & A
- What is the primary function of the LOG114AIRGVT? The LOG114AIRGVT is a precision high-speed logarithmic amplifier that computes the logarithm or log-ratio of an input current or voltage relative to a reference current or voltage.
- What is the input dynamic range of the LOG114AIRGVT? The input dynamic range is from 100pA to 10mA, spanning eight decades.
- What are the operating temperature ranges for the LOG114AIRGVT? The specified temperature range is -5°C to +75°C, and it can operate from -40°C to +85°C.
- Can the LOG114AIRGVT operate on a single supply? Yes, it can operate on either a bipolar (±5V) or a single (+5V) supply.
- What is the quiescent current of the LOG114AIRGVT? The quiescent current is ±10mA.
- What is the output scale factor of the LOG114AIRGVT? The output scale factor is 0.375V per decade of input current.
- What are some common applications of the LOG114AIRGVT? Common applications include ONET EDFA, laser optical density measurement, photodiode signal compression, log and log-ratio functions, and analog signal compression in front of ADC converters.
- What is the package type and size of the LOG114AIRGVT? The package is a small QFN-16 (4mm x 4mm).
- Does the LOG114AIRGVT include temperature drift compensation? Yes, it includes special temperature drift compensation circuitry.
- What is the frequency response of the LOG114AIRGVT? The frequency response can be up to 2.3 MHz depending on the input current level.
