60 dB-RANGE (100 nA-100 µA) Low-Cost Logarithmic Converter
The ADL5306 is a low cost micro-miniature logarithmic converter optimized for the determination of optical power in fiber-optic systems. It uses an advanced implementation of a classic translinear (junction-based) technique to provide a large dynamic range in a versatile and easily-used form. A single supply voltage of between 3 V and 5.5 V is adequate; dual supplies may optionally be used. The low quiescent current (typically 5 mA) permits use in battery-operating applications
The input current IPD of 100 nA to 100 µA applied to the INPT pin is the collector current of an optimally-scaled NPN transistor, which converts this current to a voltage (its VBE) with a precise logarithmic relationship. A second such converter is used to handle the reference current, IREF, applied to pin IREF. These input nodes are biased slightly above ground (0.5 V). This is generally acceptable for photodiode applications where the anode does not need to be grounded. Similarly, this bias voltage is easily accounted for in generating IREF. The output of the logarithmic front-end is available at pin VLOG.
Comparable Parts Click to see all in Parametric Search
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Optical and High Speed Networking ICs
Analog Devices' optical and high speed networking ICs solve a depth and breadth of challenges faced by today's designers
Closed-Loop Control of Variable Optical Attenuators with Logarithmic Analog...
By Eric J. Newman and Matthew Pilotte, Analog Devices, Inc. (Analog Dialogue, Vol 37, December 2003)
Log Amps and Directional Couplers Enable VSWR Detection
by Anil Rachakonda and Larry Hawkins, Analog Devices, Inc. (RF Design, 1/1/2007)
Logarithmic Processing Applied to Network Power Monitoring
by Eric Newman, Analog Devices, Inc.
Design a Logamp RF Pulse Detector
by Eamon Nash
(Microwaves & RF, January 1, 2000)
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.