MAX8845W, MAX8845X, MAX8845Y, MAX8845Z 28V Linear Li+ Battery Chargers with Battery Detection and Overvoltage-Protected Output

Description

The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W are intelligent, stand-alone constant-current, constant-voltage (CCCV), thermally regulated linear chargers designed for charging a single-cell lithium-ion (Li+) battery. The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W integrate a current-sense circuit, MOSFET pass element, thermal-regulation circuitry, and eliminate the external reverse-blocking Schottky diode to create the simplest and smallest charging solutions for handheld equipment.

The ICs control the charging sequence from the pre-qualification state through constant current fast-charge, top-off charge, and full-charge indication. Proprietary thermal-regulation circuitry limits the die temperature during fast-charging or when the ICs are exposed to high ambient temperatures, allowing maximum charging current without damaging the ICs.

The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W achieve high flexibility by providing adjustable fast-charge currents (SETI) and an adjustable top-off current threshold (MIN) through external resistors. The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W feature a booting assistant circuit that distinguishes input sources and battery connection and provides an enable signal (ABO—MAX8845Z and active-low ABO—MAX8845Y/MAX8845X/MAX8845W) for system booting.

The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W also integrate an overvoltage-protected output (SAFEOUT) for low voltage-rated USB or charger inputs in system, and a battery-pack detection circuit (DETBAT) that disables the charger when the battery pack is absent. Other features include an active-low control input (active-low EN), an active-low input power source detection output (active-low POK), and a fully charged top-off threshold detection output (active-low CHG).

The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W accept an input supply range from 4.25V (4.4V for MAX8845W only) to 28V, but disable charging if the supply voltage exceeds +7.5V (+8.0V for MAX8845X only) to protect against unqualified or faulty AC adapters. The ICs operate over the extended temperature range (-40°C to +85°C) and are available in a compact 12-pin, thermally enhanced thin QFN, 3mm x 3mm package (0.8mm max height).

An evaluation kit is available: MAX8845ZEVKIT

Key Features		Applications/Uses
CCCV, Thermally Regulated Linear 1-Cell Li+ Battery Charger No External MOSFET, Reverse Blocking Diode, or Current-Sense Resistor Programmable Fast-Charge Currents (1A_RMS max) Programmable Top-Off Current Threshold (MIN) Input Overvoltage Protected 4.7V Output (MAX8845Z/MAX8845Y/MAX8845W) or 4.85V (MAX8845X) (SAFEOUT) Proprietary Die Temperature Regulation Control (+115°C) 4.25V (4.4V for MAX8845W only) to 28V Input Voltage Range with Input Overvoltage Protection Above +7.5V (+8.0V for MAX8845X only) Low-Dropout Voltage (300mV at 500mA) Input Power-Source Detection Output (Active-Low POK), Charge Status Output (Active-Low CHG), Charge-Enable Input (Active-Low EN) Output for Autobooting (ABO—MAX8845Z, Active-Low ABO—MAX8845Y/MAX8845X/MAX8845W) Tiny, 3mm x 3mm 12-Pin Thin QFN Package, 0.8mm Height (max)		Bluetooth® Equipment Cellular and Cordless Phones Charging Cradles and Docks Digital Still Cameras MP3 Players Smart Phones and PDAs USB Appliances

Key Specifications: Battery Chargers

Part Number

Cell Chemistry

Lithium Ion Cells

Protected V_IN
(V)

Charging V_IN
(V)

Charge Rate Set by

Max. I_CHG
(A)

Charge Termination

Charge Regulation

Features

EV Kit

Oper. Temp.
(°C)

Package/Pins

max

≥

MAX8845

Li-Ion

Li-Polymer

Resistor

External Control

Linear

Internal FET/Transistor

Thermal Die Regulation

USB Input

-40 to +85

See Data Sheet/

See All Battery Chargers (60)

Reliability Reports

	Reliability Report: MAX8845Y.pdf MAX8845Z.pdf
	Show FIT data for:
	Request Reliability Report for:

Ordering Information

Notes:

Other options and links for purchasing parts are listed at: http://www.maxim-ic.com/sales.
Didn't Find What You Need? Ask our applications engineers. Expert assistance in finding parts, usually within one business day.
Part number suffixes: T or T&R = tape and reel;+ = RoHS/lead-free;# = RoHS/lead-exempt. More: SeeFull Data Sheet or Part Naming Conventions.
* Some packages have variations, listed on the drawing. "PkgCode/Variation" tells which variation the product uses. Note that "+", "#", "-" in the part number suffix describes RoHS status. Package drawings may show a different suffix character.

Devices: 1-8 of 8

MAX8845W

Free
Sample

Buy

Status

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX8845WETC+

Active

TQFN;12 pin;9.6 mm²
Outline Drawing: 21-0136 (PDF)
Land Pattern: 90-0019 (PDF)
Use pkgcode/variation: T1233+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8845WETC+T

Active

TQFN;12 pin;9.6 mm²
Outline Drawing: 21-0136 (PDF)
Land Pattern: 90-0019 (PDF)
Use pkgcode/variation: T1233+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8845X

Free
Sample

Buy

Status

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX8845XETC+

Active

TQFN;12 pin;9.6 mm²
Outline Drawing: 21-0136 (PDF)
Land Pattern: 90-0019 (PDF)
Use pkgcode/variation: T1233+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8845XETC+T

Active

TQFN;12 pin;9.6 mm²
Outline Drawing: 21-0136 (PDF)
Land Pattern: 90-0019 (PDF)
Use pkgcode/variation: T1233+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8845Y

Free
Sample

Buy

Status

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX8845YETC+

Active

TQFN;12 pin;9.6 mm²
Outline Drawing: 21-0136 (PDF)
Land Pattern: 90-0019 (PDF)
Use pkgcode/variation: T1233+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8845YETC+T

Active

TQFN;12 pin;9.6 mm²
Outline Drawing: 21-0136 (PDF)
Land Pattern: 90-0019 (PDF)
Use pkgcode/variation: T1233+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8845Z

Free
Sample

Buy

Status

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX8845ZETC+

Active

TQFN;12 pin;9.6 mm²
Outline Drawing: 21-0136 (PDF)
Land Pattern: 90-0019 (PDF)
Use pkgcode/variation: T1233+4*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX8845ZETC+T

Active

TQFN;12 pin;9.6 mm²
Outline Drawing: 21-0136 (PDF)
Land Pattern: 90-0019 (PDF)
Use pkgcode/variation: T1233+4*