MCP73843-420I/MS Microchip Integrated Circuit (Small Outline Packages) In Stock

Microchip MCP73843-420I/MS is a single-cell Li-Ion battery charge controller with 4.2 V preset termination voltage, constant current/constant voltage algorithm, and programmable charge current via external resistor. Available in MSOP-8 package, RoHS compliant, in stock with worldwide shipping.

ACTIVEIntegrated CircuitVerified Jun 2026
Package / Visual Reference
MCP73843-420I/MSSmall Outline Packages
Quick Facts
Manufacturer
Microchip
Package
Small Outline Packages
Pin Count
8
Lifecycle
ACTIVE
Category
Integrated Circuit
Price
From $1.2588(MOQ 1)
Temp Range
-40.0°C to 85.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

Key Features

  • Preset 4.2 V termination voltage for standard Li-Ion single-cell charging with ±1% accuracy using CC/CV algorithm without firmware overhead
  • Programmable charge current set by a single external resistor from 15 mA to 500 mA supporting both thin-film and cylindrical Li-Ion cell capacities
  • Integrated charge status output and preconditioning for deeply discharged cells below 3 V enabling safe recovery charging in portable electronics designs

Applications

The MCP73843-420I/MS provides standalone single-cell Li-Ion charging for portable electronics such as Bluetooth headsets, handheld instruments, and wearable fitness devices where a USB 5 V or wall adapter powers the charge circuit directly without a host microcontroller. Its external resistor-set charge current allows designers to match charge rate to cell capacity, supporting 100 mA for small 300 mAh pouch cells up to 500 mA for larger 1000 mAh cylindrical formats. The MSOP-8 package with minimal external components reduces BOM count and PCB area, making it a low-cost alternative to integrated PMIC solutions in simple single-battery products.

Specifications

Pbfree CodeYes
Manufacturer Package CodeMSOP-8
Reach Compliance CodeCompliant
Factory Lead Time6Weeks
YTEOL9
Adjustable ThresholdYES
Analog IC - Other TypeBATTERY MONITOR
JESD-30 CodeS-PDSO-G8
JESD-609 Codee3
Number of Channels1
Number of Functions1
Package Body MaterialPLASTIC/EPOXY
Package Equivalence CodeTSSOP8,.19
Package ShapeSQUARE
Package StyleSMALL OUTLINE, THIN PROFILE, SHRINK PITCH
Peak Reflow Temperature (Cel)260
Qualification StatusNot Qualified
Screening LevelTS 16949
Supply Current-Max (Isup)4mA
Supply Voltage-Max (Vsup)12V
Supply Voltage-Min (Vsup)4.5V
Supply Voltage-Nom (Vsup)5.2V
Surface MountYES
TechnologyCMOS
Temperature GradeINDUSTRIAL
Terminal FinishMatte Tin (Sn)
Terminal FormGULL WING
Terminal Pitch0.65mm
Terminal PositionDUAL
Threshold Voltage-Nom+4.2V
Time@Peak Reflow Temperature-Max (s)40
PackageSmall Outline Packages

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
Moisture Sensitivity LevelMSL 1
ECCNEAR99
HTS Code8542.39.00.01
Country of OriginThailand

Datasheet

MCP73843-420I/MS Datasheet Download

Official datasheet from Microchip

Alternate & Equivalent Parts

No known alternates. Submit an RFQ and our team can suggest alternatives.

Frequently Asked Questions

What termination voltage does the MCP73843-420I/MS use, and how accurate is it for protecting Li-Ion cells?

The MCP73843-420I/MS uses a factory-preset 4.2 V charge termination voltage with ±1% accuracy, meaning the actual cutoff falls between 4.158 V and 4.242 V. This tight tolerance prevents Li-Ion cell overcharge above 4.2 V while maximizing capacity utilization, complying with cell manufacturer safety requirements without requiring an external precision reference or MCU firmware.

How is the charge current configured on the MCP73843, and what range does it support?

Charge current on the MCP73843 is set by a single external resistor connected to the PROG pin. The resistor value is calculated as approximately 1000 V/A divided by the desired charge current in amperes, enabling programmable rates from 15 mA for small 30 mAh pouch cells up to 500 mA for 1000 mAh cylindrical Li-Ion cells without firmware or DAC components.

Does the MCP73843-420I/MS support preconditioning of deeply discharged Li-Ion cells, and why is this important?

Yes, the MCP73843-420I/MS applies a low preconditioning current of approximately 10% of the programmed fast charge current when cell voltage is below 3 V. This slow-rate recovery phase prevents thermal runaway in cells discharged below the safe low-voltage limit, recovering cell capacity safely before transitioning to the full constant-current phase at voltages above 3 V.

What external component count does a typical MCP73843-420I/MS Li-Ion charger circuit require?

A complete MCP73843 charger circuit requires only the MSOP-8 IC, a single charge-current programming resistor, one input decoupling capacitor of 1 µF to 10 µF, and one output bypass capacitor, totaling 4 components. This minimal BOM and small 5 mm x 3 mm board footprint makes it the cost-effective solution for USB-charged single-cell product designs.

In what portable applications is the MCP73843-420I/MS preferred over a fully integrated PMIC with charging?

The MCP73843-420I/MS is preferred in cost-sensitive single-cell designs such as Bluetooth earbuds, portable sensors, and handheld barcode scanners where Li-Ion charging is the only power management function needed and a full PMIC's multiple buck converters and LDOs add unnecessary cost and quiescent current exceeding 1 mA. The dedicated charge controller's simplicity reduces firmware complexity and eliminates I2C configuration overhead.

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About Microchip

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AvailabilityIn Stock
Reference Price (USD)
From $1.2588
Buy from 1pc · Factory-direct pricing
Qty.Unit PriceExt. Price
1+$1.7600$1.76
25+$1.4700$36.75
50+$1.3600$68.00
100+$1.3059$130.59
200+$1.2600$252.00
500+$1.2588$629.40
pcs
Unit price: $1.7600 · Total: $1.76

In Stock · 24h Response · Worldwide Shipping

Lead Time3-7 business days
MOQFrom 1 piece
ShippingDHL / FedEx / UPS
OriginChina (Authorized)

Response within 24 hours · Worldwide shipping

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