Analog Devices Inc. ADA4351-2 Precision Programmable Gain TIA

Analog Devices ADA4351-2 Precision Programmable Gain Transimpedance Amplifier (PGTIA) is a compact, monolithic, dual-channel, precision PGTIA. The ADA4351-2 is a breakthrough solution for precisely measuring small currents over a wide dynamic range. The precision of the ADA4351-2 over a wide temperature range of −40°C to +125°C enables users to perform one calibration of the end equipment at room temperature, thereby saving test time and cost. The ADA4351-2 integrates two low-off leakage current switches per channel, and the gain is programmable using two user-selectable external resistors to provide a flexible, fully functional compact PGTIA solution. Separate analog and digital supplies allow the amplifier of the ADA4351-2 to operate on bipolar supplies, while the integrated logic level shifting allows the digital interface to remain ground-referenced. Additionally, with its robust output stage and low noise, the ADA4351-2 can directly drive 16-bit precision analog-to-digital converters (ADCs, such as AD4696), providing a complete analog front-end (AFE) to address the most challenging precision current measurement applications.

The Analog Devices ADA4351-2 is offered in a 3mm × 3mm LFCSP, reducing the printed circuit board (PCB) area by up to 70% relative to a discrete design using standalone operational amplifiers (op amps) and switches. Additionally, there is no exposed pad (EPAD) on the back side of the LFCSP, eliminating the need for vias and allowing routing on all layers of the PCB beneath the device. This feature further reduces the board area and provides the most compact PGTIA and AFE solution.

Features

  • Small, dual-channel, complete PGTIA and AFE solution
  • 16-lead LFCSP, 3mm × 3mm small size package
  • Integrated switches, two external gains per channel
  • Wide input current dynamic range from picoamps to milliamps
  • Excellent DC precision
    • Low offset voltage of ±100μV maximum, 25°C
    • Low offset voltage drift of ±0.85μV/°C maximum, -40°C to +125°C
    • Low input bias current of ±9pA maximum, 25°C
    • Low switch off leakage current of ±90pA maximum (-40°C to +125°C)
  • The integrated architecture eliminates gain error due to switch resistance
  • Single-supply operation of +2.7V to +5.5V or dual-supply operation of ±1.85V to ±2.75V
  • Wide gain bandwidth product of 8.5MHz
  • -40°C to +125°C wide operating temperature range

Applications

  • Precision current to voltage (I to V) conversion
  • Programmable gain TIAs
  • Photodetector interface and amplification
  • Optical networking equipment
  • Optical power measurement
  • Instrumentation-spectroscopy and chromatography
  • Precision data acquisition systems (DAQ)

Typical Application Diagram

Application Circuit Diagram - Analog Devices Inc. ADA4351-2 Precision Programmable Gain TIA

Analog Devices Inc. ADA4351-2 Precision Programmable Gain TIA