Overview

Features and Benefits

  • 4-layer printed circuit board (PCB), 53 mm × 72 mm form factor
  • Resistor programmable log slope and intercept
  • Single-or dual-supply operation
  • Full two argument logarithmic computation
  • On-board precision 100 nA reference
  • Optimized for very fast response at all input currents
    • Overall bandwidth of >4 MHz for inputs >1 μA
    • Bandwidth: 25 kHz at input of 1 nA and 350 kHz at 10 nA
  • 10 decades of input range: 1 pA to 10 mA
  • Law conformance: ±0.25 dB from 100 pA to 100 μA
  • Log ratio or fixed-intercept operation
  • On-board precision 1.5 V and 2.0 V voltage references
  • Adaptive photodiode (PD) bias for low dark current
  • Default log slope of 10 mV/dB at VLOG pin

Product Details

This user guide refers to the ADL5304 evaluation board, which allows users to connect the ADL5304 precision log amplifier to current sources with simple SMA connections or, with modification of the default configuration, to mount a photodiode to the INUM input for optical power level applications.

The ADL5304 evaluation board is laid out to minimize errors due to leakage into the sensitive INUM and IDEN nodes through driven guards.

Slope and logarithmic intercept are programmable through on-chip resistors and can be further optimized for specific applications using external resistors. Additional components can be added to optimize filtering for specific applications.

Adaptive photodiode bias is available using the IMON output to optimize photodiode response and dark current.

Full details about the part are available in the ADL5304 data sheet, which should be consulted when using the ADL5304-EVALZ.

Documentation & Resources