Top

Precision Transimpedance Logarithmic Amplifier with Over 5 Decades of Dynamic Range

Product Details

The MAX4206 logarithmic amplifier computes the log ratio of an input current relative to a reference current (externally or internally generated) and provides a corresponding voltage output with a default 0.25V/decade scale factor. The device operates from a single +2.7V to +11V supply or from dual ±2.7V to ±5.5V supplies and is capable of measuring five decades of input current across a 10nA to 1mA range.

The MAX4206's uncommitted op amp can be used for a variety of functions, including filtering noise, adding offset, and adding additional gain. A 0.5V reference is also included to generate an optional precision current reference using an external resistor, which adjusts the log intercept of the MAX4206. The output-offset voltage and the adjustable scale factor are also set using external resistors.

The MAX4206 is available in a space-saving 16-pin thin QFN package (4mm x 4mm x 0.8mm), and is specified for operation over the -40°C to +85°C extended temperature range.

Key Features

  • Single Supply Capability Reduces System Power Supply Requirements
    • +2.7V to +11V Single-Supply Operation
    • Also Supports ±2.7V to ±5.5V Dual-Supply Operation if Required
  • Wide Dynamic Range Supports Most Photodiode Current Measurement Applications
    • 5 Decades of Dynamic Range (10nA to 1mA)
    • Monotonic Over a 1nA to 1mA Range
    • Adjustable Output Scale Factor
    • 0.25V/Decade Internally Trimmed Output Scale Factor
    • Adjustable Output Offset Voltage
    • Internal 10nA to 10µA Reference Current Source
    • 0.5V Input Common-Mode Voltage
  • Small Package and Few External Components Saves Space and Simplifies Design-In
    • 16-Pin TQFN Package (4mm x 4mm x0.8mm)

Applications/Uses

  • Analog Signal Processing
  • Medical Instrumentation
  • Photodiode Current Monitoring
  • Portable Instrumentation
Parametric specs for Logarithmic Amplifiers (Log Amps)
VSUPPLY (Single) (V) (min) 2.7
VSUPPLY (Single) (V) (max) 11
VSUPPLY (Dual) (±V) (min) 2.7
VSUPPLY (Dual) (±V) (max) 5.5
ICC (mA) (typ) 3.9
Log. Slope (mV/ decade) 250
Dynamic Range (dB) 100
Package/Pins TQFN/16
Oper. Temp. (°C) -40 to +85
Budgetary
Price (See Notes)
$1.09 @1k
Parametric specs for Transimpedance Amplifiers (TIA)
Target Oper. Range (Gbps) <1
Data Rate (Mbps) (min) 0.005
VSUPPLY (V) 5
ICC (mA) (typ) 3.9
Input Noise (nA) (max) 17000
Bandwidth (MHz) (min) 5
IIN (µA) (max) 10
Package/Pins TQFN/16
View More

Simplified Block Diagram

MAX4206: Typical Operating Circuit MAX4206: Typical Operating Circuit Zoom icon

Technical Docs

Design & Development

Click any title below to view the detail page where available.

Description

The MAX4206 evaluation kit (EV kit) is a fully assembled and tested surface-mount circuit board that demonstrates the MAX4206 logarithmic amplifier. The MAX4206 computes the log ratio of an input current relative to a reference current and provides a corresponding voltage output with a default 0.25V/decade scale factor. The EV kit operates from a single +2.7V to +11V supply or from dual ±2.7V to ±5.5V supplies, with the ability to select one of four reference currents.

The MAX4206 EV kit can be used to evaluate the MAX4207 by changing the IC and the input RC networks R1, R2, C7, and C8.

View Details

Features

  • +2.7V to +11V Single-Supply Operation or ±2.7V to ±5.5V Dual-Supply Operation
  • Selectable 10nA/100nA/1µA/10µA On-Board Reference Current
  • Adjustable Output Scale Factor
  • Surface-Mount Construction
  • Fully Assembled and Tested

/en/design/design-tools/ee-sim.html?

SIMULATION MODELS

MAX4206 Orcad Library

Download

SIMULATION MODELS

MAX4206 Macromodel

Download

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal.

Parameters

Parametric specs for Logarithmic Amplifiers (Log Amps)
VSUPPLY (Single) (V) (min) 2.7
VSUPPLY (Single) (V) (max) 11
VSUPPLY (Dual) (±V) (min) 2.7
VSUPPLY (Dual) (±V) (max) 5.5
ICC (mA) (typ) 3.9
Log. Slope (mV/ decade) 250
Dynamic Range (dB) 100
Package/Pins TQFN/16
Oper. Temp. (°C) -40 to +85
Budgetary
Price (See Notes)
$1.09 @1k
Parametric specs for Transimpedance Amplifiers (TIA)
Target Oper. Range (Gbps) <1
Data Rate (Mbps) (min) 0.005
VSUPPLY (V) 5
ICC (mA) (typ) 3.9
Input Noise (nA) (max) 17000
Bandwidth (MHz) (min) 5
IIN (µA) (max) 10
Package/Pins TQFN/16

Key Features

  • Single Supply Capability Reduces System Power Supply Requirements
    • +2.7V to +11V Single-Supply Operation
    • Also Supports ±2.7V to ±5.5V Dual-Supply Operation if Required
  • Wide Dynamic Range Supports Most Photodiode Current Measurement Applications
    • 5 Decades of Dynamic Range (10nA to 1mA)
    • Monotonic Over a 1nA to 1mA Range
    • Adjustable Output Scale Factor
    • 0.25V/Decade Internally Trimmed Output Scale Factor
    • Adjustable Output Offset Voltage
    • Internal 10nA to 10µA Reference Current Source
    • 0.5V Input Common-Mode Voltage
  • Small Package and Few External Components Saves Space and Simplifies Design-In
    • 16-Pin TQFN Package (4mm x 4mm x0.8mm)

Applications/Uses

  • Analog Signal Processing
  • Medical Instrumentation
  • Photodiode Current Monitoring
  • Portable Instrumentation

Description

The MAX4206 logarithmic amplifier computes the log ratio of an input current relative to a reference current (externally or internally generated) and provides a corresponding voltage output with a default 0.25V/decade scale factor. The device operates from a single +2.7V to +11V supply or from dual ±2.7V to ±5.5V supplies and is capable of measuring five decades of input current across a 10nA to 1mA range.

The MAX4206's uncommitted op amp can be used for a variety of functions, including filtering noise, adding offset, and adding additional gain. A 0.5V reference is also included to generate an optional precision current reference using an external resistor, which adjusts the log intercept of the MAX4206. The output-offset voltage and the adjustable scale factor are also set using external resistors.

The MAX4206 is available in a space-saving 16-pin thin QFN package (4mm x 4mm x 0.8mm), and is specified for operation over the -40°C to +85°C extended temperature range.

Simplified Block Diagram

MAX4206: Typical Operating Circuit MAX4206: Typical Operating Circuit Zoom icon

Technical Docs

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal.