MAX6846:Low-Power, Adjustable Battery Monitors with Hysteresis and Integrated µP Reset

Adjustable Single-/Dual-Output Battery Monitors with Hysteresis and µP Supervisor Circuits in SOT23

The MAX6846–MAX6849 are a family of ultra-low-power battery monitors with integrated microprocessor (µP) supervisors. The user-adjustable battery monitors are offered with single or dual low-battery output options that can be used to signal when the battery is OK (enabling full system operation), when the battery is low (for low-power system operation), and when the battery is dead (to disable system operation). These devices also have an independent µP supervisor that monitors VCC and provides an active-low reset output. A manual reset function is available to reset the µP with a pushbutton. The MAX6846–MAX6849 are ideal for single-cell lithium-ion (Li+) or multicell alkaline/NiCd/NiMH applications. When the battery voltage drops below each adjusted low threshold, the low-battery outputs are asserted to alert the system. When the voltage rises above the adjusted high thresholds, the outputs are deasserted after a 150ms minimum timeout period, ensuring the voltages have stabilized before power circuitry is activated or providing microprocessor reset timing. These devices have user-adjustable battery threshold voltages, providing a wide hysteresis range to prevent chattering that can result due to battery recovery after load removal. Single low-battery outputs are supplied by the MAX6846/MAX6847 and dual low-battery outputs are supplied by the MAX6848/MAX6849. All battery monitors have open-drain low-battery outputs. The MAX6846–MAX6849 monitor system voltages (VCC) from 1.8V to 3.3V with seven fixed reset threshold options. Each device is offered with two minimum reset timeout periods of 150ms or 1200ms. The MAX6846/MAX6848 are offered with an open-drain active-low RESET output and the MAX6847/MAX6849 are offered with a push-pull active-low RESET output. The MAX6846–MAX6849 are offered in a SOT23 package and are fully specified over a -40°C to +85°C temperature range.

Key Features
  • User-Adjustable Thresholds for Monitoring Single-Cell Li+ or Multicell Alkaline/NiCd/NiMH Applications
  • Single and Dual Low-Battery Output Options
  • Independent µP Reset with Manual Reset
  • Factory-Set Reset Thresholds for Monitoring 1.8V to 3.3V Systems
  • Available with 150ms (min) or 1.2s (min) VCC Reset Timeout Period Options
  • 150ms (min) Active-Low LBO Timeout Period
  • Immune to Short-Battery Voltage Transients
  • Low Current (2.5µA, typ at 3.6V)
  • -40°C to +85°C Operating Temperature Range
  • Small 8-Pin SOT23 Packages
MAX6846, MAX6847, MAX6848, MAX6849: Pin Configuration
MAX6846, MAX6847, MAX6848, MAX6849: Pin Configuration
Applications/Uses
  • Battery-Powered Systems (Single-Cell Li+ or Multicell NiMH, NiCd, Alkaline)
  • Cell Phones/Cordless Phones
  • Digital Cameras
  • Electronic Toys
  • MP3 Players
  • Pagers
  • PDAs
  • Portable Medical Devices
DataSheet
titleDownload file
MAX6846-MAX6849 Data SheetMAX6846-MAX6849.pdf
Parametrics
Part NumberReset Thresh.
(V)
Reset OuttRESETWatchdog FeatureSupervisor FeaturesReset Thresh. Accur.
(%)
ICC
(µA)
Package/PinsBudgetary
Price
min@ +25°CmaxSee Notes
MAX68460 to 1.2
1.2 to 1.8
1.8 to 2.5
2.5 to 3.3
3.3 to 5.5
Active Low
Open Drain
85ms to 300ms
>1s
No WatchdogManual Reset
Power Fail Comparator/Low Battery Detect
1.57SOT/8$1.50 @1k
MAX6847Active Low
Push-Pull
Manual Reset
Power Fail Comparator/Low Battery Detect
SOT/8$1.50 @1k
MAX6848Active Low
Open Drain
Power Fail Comparator/Low Battery DetectSOT/8$1.93 @1k
Related Products
  • MAX6439:Low-Power, Single-/Dual-Level Battery Monitors with Hysteresis and Integrated µP Reset
  • MAX6442:Low-Power, Single-/Dual-Level Battery Monitors with Hysteresis and Integrated µP Reset
  • MAX6427:Low-Power, Single/Dual-Level Battery Monitors with Hysteresis
  • MAX6438:Low-Power, Single/Dual-Level Battery Monitors with Hysteresis
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6846KARD3+ActiveSOT,;8 pin;9 mm²-40°C to +85°CLead Free
MAX6846KARD3+TActiveSOT,;8 pin;9 mm²-40°C to +85°CLead Free
MAX6846KARD3-TNo Longer AvailableMAX6846KARD3+TSOT,;8 pin;9 mm²-40°C to +85°CNo
MAX6846KARD7+TActiveSOT;-40°C to +85°CSee data sheet
MAX6846KARD7-TNo Longer AvailableSee data sheet
MAX6846KASD3+TActiveSOT,;8 pin;9 mm²-40°C to +85°CLead Free
MAX6846KASD3-TNo Longer AvailableMAX6846KASD3+TSOT,;8 pin;9 mm²-40°C to +85°CNo
MAX6846KASD7+TActiveSOT;-40°C to +85°CSee data sheet
MAX6846KASD7-TNo Longer AvailableSee data sheet
MAX6846KATD3+TActiveSOT;-40°C to +85°CSee data sheet
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6846KATD3-TNo Longer AvailableSee data sheet
MAX6846KATD7+TActiveSOT;-40°C to +85°CSee data sheet
MAX6846KATD7-TNo Longer AvailableSee data sheet
MAX6846KAVD3+TActiveSOT;-40°C to +85°CSee data sheet
MAX6846KAVD3-TNo Longer AvailableSee data sheet
MAX6846KAVD7+TActiveSOT;-40°C to +85°CSee data sheet
MAX6846KAVD7-TNo Longer AvailableSee data sheet
MAX6846KAWD3-TNo Longer AvailableMAX6846KAWD3+TSOT,;8 pin;9 mm²-40°C to +85°CNo
MAX6846KAWD7+TActiveSOT;-40°C to +85°CSee data sheet
MAX6846KAWD7-TNo Longer AvailableSee data sheet
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6846KAYD3+TActiveSOT;-40°C to +85°CSee data sheet
MAX6846KAYD3-TNo Longer AvailableMAX6846KAYD3+TSee data sheet
MAX6846KAYD7+TActiveSOT;-40°C to +85°CSee data sheet
MAX6846KAYD7-TNo Longer AvailableSee data sheet
MAX6846KAZD3+TActiveSOT;8 pin-40°C to +85°CSee data sheet
MAX6846KAZD3-TNo Longer AvailableMAX6846KAZD3+TSOT,;8 pin;9 mm²-40°C to +85°CNo
MAX6846KAZD7+TActiveSOT;-40°C to +85°CSee data sheet
MAX6846KAZD7-TNo Longer AvailableSee data sheet
MAX6846-MAX6849.pdf MAX6848
引脚配置 MAX6849