SGM41526中文資料圣邦股份數(shù)據(jù)手冊PDF規(guī)格書

FEATURES

● 4A Synchronous 1.6MHz PWM Charger

? Cycle-by-Cycle Current Limit

? Integrated 24V Switching MOSFETs

? Integrated Bootstrap Diode

? Digital Soft-Start

● Up to 95.2% Charge Efficiency

● 30V Absolute Maximum Input Voltage Rating with

Adjustable Over-Voltage Threshold

● 4.5V to 22V Input Operating Voltage Range

● Automatic Power Path Selector (Battery/Adapter)

● Dynamic Power Management (DPM)

● Battery Charge Voltage

? SGM41526: Select 2-, 3-, or 4-Cell with 4.2V/Cell

? SGM41527: Adjustable Charge Voltage

● 18μA Battery Current (No Adapter)

● 1.3mA Input Current (Charge Disabled)

● High Accuracy

? ±0.4% Charge Voltage Regulation

? ±5% Charge Current Regulation

? ±4% Input Current Regulation

● Safety

? Thermal Regulation (Current Limit for TJ = +120℃)

? Thermal Shutdown

? Battery Thermistor Sense Hot/Cold Charge Suspend

? Input Under-Voltage Lockout (UVLO)

? Input Over-Voltage (ACOV) Protection

APPLICATIONS

Tablet PCs

Portable Terminals and Printers

Portable Medical Equipment

Battery Backup Systems

GENERAL DESCRIPTION

The SGM41526 and SGM41527 are stand-alone Li-Ion and

Li-polymer battery chargers. The PWM switches are integrated

inside and they can automatically select the power path. They

also include gate drivers for external power path selector

MOSFETs. The synchronous PWM controller runs at a fixed

frequency (1.6MHz) and is capable of providing accurate

regulation of charge voltage, charge current and input current.

They are capable of providing continuous battery pack

temperature monitoring in which the charge is only allowed

when the temperature is within the desired range. The

SGM41526 can charge 2-, 3- or 4-cell (selected by CELL pin);

while the SGM41527 has an adjustable charge voltage for up

to 4 cells. In the SGM41527, the FB pin is used for charge

voltage regulation (feedback) using an internal 2.1V reference

and comparator.

Typically, a full battery charging cycle has three consequent

phases: pre-conditioning, constant current and constant

voltage. The charge current is small during the pre-conditioning

phase in which battery is heavily depleted. When the battery

voltage exceeds a threshold voltage, the charge current

increases to its maximum (fast charge current) until the battery

voltage reaches its regulation level. Then the voltage is

regulated and charge current drops. The starting phase is

determined by the initial battery voltage. In constant voltage

condition, the charge current drops automatically. When it

decreases below 10% of the fast charge value, charging is

terminated. A programmable safety charge timer is provided to

prevent prolonged charging if it is not naturally terminated for

any reason. When the battery voltage falls below recharge

threshold, charge cycle is automatically started (or restarted).

If the input voltage falls below the battery voltage, the device

enters sleep mode. In sleep mode, the quiescent current is

very low.

The SGM41526 and SGM41527 use dynamic power

management (DPM) to prevent overload of the input source

(AC adaptor). With DPM, the output charge current is reduced

if the input power limit is reached. The input current is sensed

and controlled by a precision current-sense amplifier to limit the

input power.

Gate driver outputs are provided for power path selection that

can be achieved by three external switches. Two N-type

back-to-back MOSFETs (Q1, Q2) are used as input pair

(adapter power in and reverse blocking control) along with a

P-type (Q3) that is used to control the battery connection to the

system bus. The system is powered from adapter by Q1 and

Q2 on if a qualified adapter is present. Otherwise, the system is

connected to the battery by Q3. And with power path control,

the battery cannot feed back to the input.

The SGM41526 and SGM41527 can charge the battery from a

DC source with a voltage up to 22V. This range covers

common adapter voltages and the car battery voltage. The

qualified adapter range is adjustable by OVPSET pin. If the

input voltage is out of the range, Q1 and Q2 will not be turned

on.

For 1-cell applications (only applicable to SGM41527), when

the battery is not removable, the design can be simplified by

direct connection of the battery to the system. Therefore, when

the input source is overloaded, the battery can help power the

system automatically.

The SGM41526 and SGM41527 are available in a Green

TQFN-5.5×3.5-24L package. It can operate over an ambient

temperature range of -40℃ to +85℃.