FEATURES

● High Efficiency, 1.5MHz, Synchronous Buck Charger

? 95% Charge Efficiency at 1A from 5V Input

? Selectable PFM Mode for Light Load Efficiency

● Boost Mode Support

? Boost Efficiency of 95.5% at 0.5A and 95% at 1A

? PMID_GD Pin Control External P-MOSFET for

Protection against Fault Conditions

? Selectable PFM Mode for Light Load Operations

● Single Input for USB or High Voltage Adaptors

? 3.9V to 13.5V Operating Input Voltage Range

? 22V Absolute Maximum Input Voltage Rating

? Programmable Input Current Limit and Dynamic

Power Management (IINDPM, 100mA to 3.2A with

100mA Resolution) to Support USB 2.0 and USB 3.0

Standards and High Voltage Adaptors

? Maximum Power Tracking by Programmable Input

Voltage Limit (VINDPM) with Selectable Offset

? VINDPM Tracking of Battery Voltage

● High Battery Discharge Efficiency with 10mΩ Switch

● Narrow Voltage DC (NVDC) Power Path Management

? Instant-On with No or Highly Depleted Battery

? Ideal Diode Operation in Battery Supplement Mode

● Ship Mode, Wake-Up and Full System Reset Capability

by Battery FET Control

● Flexible Autonomous and I2

C Operation Modes for

Optimal System Performance

● Fully Integrated Switches, Current Sense and

Compensation

● External Direct Charging Path Enable Output

● 9μA Ship Mode Low Battery Leakage Current

● High Accuracy

? ±0.5% Charge Voltage Regulation (8mV/Step)

? ±5% Charge Current Regulation at 1.26A

? ±7.5% Input Current Regulation at 0.5A

● Safety

? Battery Temperature Sensing (Charge/Boost Modes)

? Thermal Regulation and Thermal Shutdown

? Input Under-Voltage Lockout (UVLO)

? Input Over-Voltage (ACOV) Protection

APPLICATIONS

Smart Phones, EPOS

Portable Internet Devices and Accessory

GENERAL DESCRIPTION

The SGM41518 is a battery charger and system power path

management device with integrated converter and power

switches for using with single-cell Li-Ion or Li-polymer

batteries. This highly integrated 1.26A device is capable of

fast charging and supports a wide input voltage range

suitable for wearable and earphone applications. I

2

C

programming makes it a very flexible powering and charger

design solution.

The device includes four main power switches: input reverse

blocking FET (RBFET, Q1), high-side switching FET for Buck

or Boost mode (HSFET, Q2), low-side switching FET for Buck

or Boost mode (LSFET, Q3) and battery FET that controls the

interconnection of the system and battery (BATFET, Q4). The

bootstrap diode for the high-side gate driving is also

integrated. The internal power path has a very low impedance

that reduces the charging time and maximizes the battery

discharge efficiency. Moreover, the input voltage and current

regulations provide maximum charging power delivery to the

battery with various types of input sources.

A wide range of input sources are supported, including

standard USB hosts, charging ports and USB compliant high

voltage adaptors. The SGM41518 is USB 2.0 and USB 3.0

power specifications compliant with input current and voltage

regulation. This limit is determined by the detection circuit in

the system (e.g. USB PHY).

The SGM41518 is capable of boosting the battery voltage to

supply 5V (adjustable 4.85V/5V/5.15V/5.3V) on PMID. The

Boost mode is used to charge another battery by the control

of PMID_GD. The PMID_GD pin is used to drive an external

P-MOSFET to disconnect Boost output PMID from attached

accessories.

The system voltage is regulated slightly above the battery

voltage by the power path management circuit and is kept

above the programmable minimum system voltage (3.5V by

default). Therefore, system power is maintained even if the

battery is completely depleted or removed. Dynamic power

management (DPM) feature is also included that

automatically reduces the charge current if the input current

or voltage limit is reached. If the system load continues to

increase after reduction of charge current down to zero, the

power path management provides the deficit from battery by

discharging battery to the system until the system power

demand is fulfilled. This is called supplement mode, which

prevents the input source from overloading.

Starting and termination of a charging cycle can be

accomplished without software control. The sensed battery

voltage is used to decide for starting phase of charging in one

of the three phases of charging cycle: pre-conditioning,

constant current or constant voltage. When the charge

current falls below a preset limit and the battery voltage is

above recharge threshold, the charger function will

automatically terminate and end the charging cycle. If the

voltage of a charged battery falls below the recharge

threshold, the charger begins another charging cycle.

Several safety features are provided in the SGM41518 such

as over-voltage and over-current protections, battery

temperature monitoring, charging safety timing, thermal

shutdown and input UVLO. TS pin is connected to an NTC

thermistor for battery temperature monitoring and protection

in both charge and Boost modes according to JEITA profile.

This device also features thermal regulation in which the

charge current is reduced, if the junction temperature

exceeds 80℃ or 120℃ (selectable).

Charging status is reported by the STAT output and

fault/status bits. A negative pulse is sent to the nINT output

pin as soon as a fault occurs to notify the host. BATFET reset

control is provided by nQON pin to exit ship mode or for a full

system reset.

The SGM41518 is available in a Green WLCSP-2.0×2.4-30B

package.