SMBus Dual/Quad Current Monitor

Accurate Current Measurement with Automatic Overcurrent Shutdown for Four Supply Rails

Please check latest availability status for a specific part variant.


The MAX34408 and MAX34409 are two- and four-channel current monitors that are configured and monitored with a standard I2C/SMBus serial interface. Each unidirectional current sensor offers precision high-side operation with a low full-scale sense voltage. The devices automatically sequence through two or four channels and collect the current-sense samples and average them to reduce the effect of impulse noise. The raw ADC samples are compared to user-programmable digital thresholds to indicate overcurrent conditions. Overcurrent conditions trigger a hardware output to provide an immediate indication to shut down any necessary external circuitry.
MAX34408, MAX34409: Typical Application Circuit and Block Diagram MAX34408, MAX34409: Typical Application Circuit and Block Diagram Enlarge+

Key Features

  • Enables Accurate Current Consumption Measurement on Up to Four Rails with Digital Serial Readout
    • Low 12.25mV Full-Scale Current-Sense Voltage
    • Automatic Round Robin Sequencing to Sample Each Current-Sense Input
    • Selectable Averaging to Improve Current-Sense Accuracy
    • Programmable Digital Overcurrent Thresholds with Delay Function
    • I2C/SMBus Interface with Bus Timeout
    • Register Access to Real-Time Current Measurements
  • Compatible on a Wide Range of Voltage Rails
    • Wide 2.5V to 13.2V Common-Mode Range
  • Automatic System Shutdown on Overcurrent Condition
    • Shutdown Output Provides Immediate Hardware Indication of Overcurrent


  • Base Stations
  • Industrial Controls
  • Network Switches and Routers
  • Servers
  • Smart Grid Network Systems

See parametric specs for Current Sense Amplifiers (52)

Part NumberOutput FormatCMVR
Bi-Dir. Curr. SenseVSENSE_FS
VOS @25°C
Gain Accuracy @25°C
ComparatorsReferenceOper. Temp.
minmaxminmaxtyprecomm.maxmaxSee Notes
MAX34408 Digital2.513.22.73.6830No1019122Bandgap-40 to +85
$2.54 @1k
MAX34409 4
$2.64 @1k

Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

MAX34409EVKIT: Evaluation Kit for the MAX34409
Product Reliability Reports: MAX34409.pdf 
Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C   Material Composition  

Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

Quality Management System >
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