UCSP, 1.8V, Nanopower, Beyond-the-Rails Comparators With/Without Reference

Please check latest availability status for a specific part variant.


The MAX9025–MAX9028 nanopower comparators in space-saving chip-scale (UCSP) packages feature Beyond-the-Rails™ inputs and are guaranteed to operate down to +1.8V. The MAX9025/MAX9026 feature an on-board 1.236V ±1% reference and draw an ultra-low supply current of only 1µA, while the MAX9027/MAX9028 (without reference) require just 0.6µA of supply current. These features make the MAX9025–MAX9028 family of comparators ideal for all 2-cell battery-monitoring/management applications.

The unique design of the output stage limits supply-current surges while switching, virtually eliminating the supply glitches typical of many other comparators. This design also minimizes overall power consumption under dynamic conditions. The MAX9025/MAX9027 have a push-pull output stage that sinks and sources current. Large internal-output drivers allow rail-to-rail output swing with loads up to 5mA. The MAX9026/MAX9028 have an open-drain output stage that makes them suitable for mixed-voltage system design. All devices are available in the miniature 6-bump UCSP packages.

Refer to the MAX9117 data sheet for similar comparators in 5-pin SC70 packages and the MAX9017 data sheet for similar dual comparators in 8-pin SOT23 packages.
MAX9025, MAX9026, MAX9027, MAX9028: Functional Diagram MAX9025, MAX9026, MAX9027, MAX9028: Functional Diagram Enlarge+

Key Features

  • Space-Saving UCSP Package (1mm x 1.52mm)
  • Ultra-Low Supply Current
    • 0.6µA (MAX9027/MAX9028)
    • 1µA with Reference (MAX9025/MAX9026)
  • Guaranteed to Operate Down to +1.8V
  • Internal 1.236V ±1% Reference (MAX9025/MAX9026)
  • Input Voltage Range Extends 200mV Beyond-the-Rails
  • CMOS Push-Pull Output with ±5mA Drive Capability (MAX9025/MAX9027)
  • Open-Drain Output Versions Available (MAX9026/MAX9028)
  • Crowbar-Current-Free Switching
  • Internal Hysteresis for Clean Switching
  • No Phase Reversal for Overdriven Inputs


  • 2-Cell Battery Monitoring/Management
  • Medical Instruments
  • Mobile Communications
  • Notebooks and PDAs
  • Sensing at Ground or Supply Line
  • Telemetry and Remote Systems
  • Ultra-Low-Power Systems

See parametric specs for Comparators (96)

Part NumberComparatorstPD
Input RangeVSUPPLY (Total)
ICC per Comp.
Logic OutOper. Temp.
typminmaxmaxtypmaxSee Notes
MAX9027 114000
Rail to Rail
to Neg. Rail
1.85.510.35Push-Pull-40 to +85
UCSP (B)/6
$0.48 @1k
MAX9028 Open Drain
UCSP (B)/6
$0.44 @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.

See parametric specs for Comparators + Reference (48)

Part NumberComparatorsThresh.
Internal Reference Accuracy
Prog. Hyst.VOS
Logic OutOper. Temp.
typminmaxmaxtypmaxSee Notes
MAX9025 11.2361201.85.51.7No0.35Push-Pull-40 to +85
UCSP (B)/6
$0.70 @1k
MAX9026 Open Drain
UCSP (B)/6
Product Reliability Reports: MAX9025.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 >
Environmental Management System >


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