+5V, Low-Power, 12-Bit Serial ADCs

See MAX1240 for 3V Applications

Please check latest availability status for a specific part variant.


The MAX187/MAX189 serial 12-bit analog-to-digital converters (ADCs) operate from a single +5V supply and accept a 0 to 5V analog input. Both parts feature an 8.5µs successive-approximation ADC, a fast track/hold (1.5µs), an on-chip clock, and a high-speed 3-wire serial interface.

The MAX187/MAX189 digitize signals at a 75ksps throughput rate. An external clock accesses data from the interface, which communicates without external hardware to most digital signal processors and microcontrollers. The interface is compatible with SPI, QSPI™, and MICROWIRE®.

The MAX187 has an on-chip buffered reference, and the MAX189 requires an external reference. Both the MAX187 and MAX189 save space with 8-pin PDIP and 16-pin SO packages. Power consumption is 7.5mW and reduces to only 10µW in shutdown.

Excellent AC characteristics and very low power consumption combined with ease of use and small package size make these converters ideal for remote DSP and sensor applications, or for circuits where power consumption and space are crucial.

MAX187, MAX189: Functional Diagram MAX187, MAX189: Functional Diagram Enlarge+

Key Features

  • 12-Bit Resolution
  • ±½ LSB Integral Nonlinearity (MAX187A/MAX189A)
  • Internal Track/Hold, 75kHz Sampling Rate
  • Single +5V Operation
  • Low Power
    • 2µA Shutdown Current
    • 1.5mA Operating Current
  • Internal 4.096V Buffered Reference (MAX187)
  • 3-Wire Serial Interface, Compatible with SPI, QSPI, and MICROWIRE
  • Small-Footprint 8-Pin PDIP and 16-Pin SO


  • High-Accuracy Process Control
  • Isolated Data Acquisition
  • Portable Data Logging
  • Remote Digital Signal Processing
Part NumberResolution
Input Chan.Conv. Rate
ADC ArchitectureData BusDiff/S.E. InputInternal VREF
External VREF
External VREF
Unipolar VIN
ADCmaxnominalminmaxmaxSee Notes
MAX187 12175SARSPIS.E. Only4.0962.55.254.096-80
SOIC (W)/16
$9.61 @1k
MAX189 -
SOIC (W)/16
$6.97 @1k
See All Precision ADCs (< 5Msps) (443)
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.

MAX187EVKIT: Evaluation Kit for the MAX187

Technical Documents

App Note 827 PC Serial Port Drives 12-Bit A/D Converter
App Note 439 Interfacing the MAX187 to the TMS320C3X Evaluation Module

Quality and Environmental Data

Request Reliability Report for: MAX187 
Lead-Free Package Tin (Sn) Whisker Reports
Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C  

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 >
Environmental Management System >


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