MAX921:Ultra Low-Power, Single/Dual-Supply Comparators

The MAX921–MAX924 single, dual, and quad micropower, low-voltage comparators feature the lowest power consumption available. These comparators draw less than 4µA supply current over temperature (MAX921/MAX922), and include an internal 1.182V ±1% voltage reference, programmable hysteresis, and TTL/CMOS outputs that sink and source current. Ideal for 3V or 5V single-supply applications, the MAX921–MAX924 operate from a single +2.5V to +11V supply (or a ±1.25V to ±5V dual supply), and each comparator's input voltage range swings from the negative supply rail to within 1.3V of the positive supply. The MAX921–MAX924's unique output stage continuously sources as much as 40mA. And by eliminating power-supply glitches that commonly occur when comparators change logic states, the MAX921–MAX924 minimize parasitic feedback, which makes them easier to use. The single MAX921 and dual MAX923 provide a unique and simple method for adding hysteresis without feedback and complicated equations, simply by using the HYST pin and two resistors.

Key Features
  • µMAX® Package—Smallest 8-Pin SO (MAX921/MAX922/MAX923)
  • Ultra-Low 4µA Max Quiescent Current Over Extended Temp. Range (MAX921)
  • Power Supplies:
    • Single +2.5V to +11V
    • Dual ±1.25V to ±5.5V
  • Input Voltage Range Includes Negative Supply
  • Internal 1.182V ±1% Bandgap Reference
  • Adjustable Hysteresis
  • TTL/CMOS-Compatible Outputs
  • 12µs Propagation Delay (10mV Overdrive)
  • No Switching Crowbar Current
  • 40mA Continuous Source Current
MAX921, MAX922, MAX923, MAX924: Typical Operating Circuit
MAX921, MAX922, MAX923, MAX924: Typical Operating Circuit
Applications/Uses
  • Battery-Powered Applications
  • Oscillator Circuits
  • Threshold Detectors
  • Window Comparators
DataSheet
titleDownload file
MAX921-MAX924 Data SheetMAX921-MAX924.pdf
Parametrics
Part NumberComp-
arators
tPD
(ns)
Input RangeVSUPPLY (Total)
(V)
VSUPPLY (Total)
(V)
ICC per Comp.
(µA)
VOS
(mV)
Logic OutOper. Temp.
(°C)
Package/PinsBudgetary
Price
typminmaxmaxmaxSee Notes
MAX922212000to Neg. Rail2.5111.610Push-Pull-55 to +125
-40 to +85
0 to +70
µMAX/8
PDIP(N)/8
SOIC(N)/8
$2.17 @1k

Part NumberComp-
arators
Thresh.
(V)
Internal Ref. Accuracy
(%)
tPD
(µs)
VSUPPLY
(V)
VSUPPLY
(V)
ICC
(µA)
Prog. Hyst.VOS
(mV)
Logic OutOper. Temp.
(°C)
Package/PinsBudgetary
Price
typminmaxmaxmaxSee Notes
MAX92111.1821122.5113.2Yes10TTL/CMOS-55 to +125
-40 to +85
0 to +70
µMAX/8
CDIP(N)/8
PDIP(N)/8
SOIC(N)/8
$2.96 @1k
MAX92324.5YesµMAX/8
CDIP(N)/8
PDIP(N)/8
SOIC(N)/8
$3.23 @1k
MAX92446.6NoCDIP(N)/16
PDIP(N)/16
SOIC(N)/16
$3.05 @1k
Quality and Environmental Data
MAX921-MAX924.pdf MAX924
Provide Remote Alarm for Smoke Detector MAX921
Circuit Connection Adds Current-Mode Operation to PFM Boost Converters MAX933
Simple Circuit Measures Battery Drain MAX921
Boost Converter Has High Efficiency at Light Loads MAX921
MAX921.pdf MAX921
MAX921-MAX924.pdf MAX924