SG6846ACSZ FAIRCHILD [Fairchild Semiconductor], SG6846ACSZ Datasheet

SG6846ACSZ

Manufacturer Part Number

SG6846ACSZ

Description

Highly Integrated Green-Mode PWM Controller

Manufacturer

FAIRCHILD [Fairchild Semiconductor]

Datasheet

1.SG6846ACSZ.pdf (13 pages)

Current page: 1 of 13
Download datasheet (491Kb)

Highly Integrated Green-Mode PWM Controller

FEATURES

APPLICATIONS

General-purpose switch-mode power supplies and

flyback power converters, including:

DESCRIPTION

The highly integrated SG6846A series of PWM

controllers provides features to enhance the performance

of flyback converters. To minimize standby power

TYPICAL APPLICATION

Version 1.1.1 (IAO33.0059.B1)

Two-level OCP with 1700ms delay time

Output short-circuited delay time: 100ms

Low start-up current (8µA)

Low operating current (3.7mA)

Peak-current mode operation with cycle-by-cycle

current limiting

Programmable PWM frequency with frequency

hopping

PWM frequency continuously decreasing with burst

mode at light loads

AC input brownout protection with hysteresis and

constant output power limit

Constant output power limit (full AC input range)

Internal latch circuit for OVP, OTP, and OCP

Built-in soft-start

Open-loop protection with 1700ms delay time

Power adapters

Open-frame SMPS

Specifically fit for SMPS with surge-current output

(such as for printers, scanners, motor drivers, etc.)

over-voltage protection (OVP)

- 1 -

consumption, a proprietary green-mode function provides

off-time modulation to continuously decrease the

switching frequency under light-load conditions. Under

zero-load conditions, the power supply enters burst-mode.

The SG6846A is especially designed for SMPS with

surge-current output, incorporated with a two-level OCP

function. Besides the cycle-by-cycle current limiting, if

the switching current is higher than two thirds the

peak-current

protection is activated and the SG6846A latches off.

If the switching current is higher than two thirds the

peak-current threshold for 100ms and the voltage on the

VDD pin is higher than V

are latched off immediately once V

than V

SG6846A also integrates a frequency hopping function

that reduces EMI emission of a power supply with

minimum line filters. Its built-in synchronized slope

compensation provides proprietary internal compensation

for constant output power limit over a universal AC input

range. Also, the gate output is clamped at 18V to protect

the external MOSFET from over-voltage damage.

Internal soft-start is built-in to reduce stress on the

MOSFET and start-up current during power-on period.

Other protection functions include: AC input brownout

protection with hysteresis, V

and over-temperature protection. For over-temperature

protection, an external NTC thermistor can be applied to

sense the ambient temperature. When OCP, V

OTP are activated, an internal latch circuit is used to

latch-off the controller. The PWM pulses stay latched off

until the power supply is unplugged from the main outlet.

SG6846A is available in an 8-pin SOP package.

DD-OFF

+ 1V; useful if an output short-circuit occurs.

www.sg.com.tw • www.fairchildsemi.com

threshold

DD-OFF

for

Product Specification

over-voltage protection,

1700ms,

+ 1V, the PWM pulses

September 26, 2007

voltage is lower

SG6846A

over-current

OVP, or

Related parts for SG6846ACSZ

Related keywords

SG6846ACSZ datasheet
SG6846ACSZ data sheet
SG6846ACSZ pdf datasheet
SG6846ACSZ component
SG6846ACSZ part
SG6846ACSZ distributor
SG6846ACSZ RoHS
SG6846ACSZ datasheet download