STR-X6769

Description

The STR-X6769 is a quasi-resonant topology IC designed for

SMPS applications. It shows lower EMI noise characteristics

than conventional PWM solutions, especially at greater than

2 MHz. It also provides a soft-switching mode to turn on the

by use of the resonant characteristic of primary inductance

and a resonant capacitor.

The package is a fully molded TO-3P, which contains the

controller chip (MIC) and MOSFET, enabling output power

up to 310 W at 230 VAC and 210 W at universal input. The

MOSFET at the second bottom point, to minimize an increase

of operating frequency at light output load, improving system-

level efficiency over the entire load range.

There are two standby functions available to reduce the input

powerunderverylightloadconditions.ThefirstisAuto-Standby

mode, which is internally triggered by periodic sensing, and

the other is a manual standby mode, which is executed by

clamping the secondary output. In general applications, the

manualstandbymodereducestheinputpowerfurthercompared

to Auto-Standby mode.

Features and Benefits

▪ Quasi-resonant topology IC

 Low EMI noise and soft

switching

▪ Bottom-skip mode

 Improved system efficiency over

the entire output load by avoiding increase of switching

frequency

▪ Auto-Standby mode

 Lowers input power at very light

output load condition

▪ Avalanche-guaranteed MOSFET

 Improves system-level

▪ Various protections

 Improved system-level reliability

▫ Pulse-by-pulse drain overcurrent limiting

▫ Overvoltage Protection (bias winding voltage sensing),

with latch

▫ Overload Protection with latch

▫ Maximum on-time limit

Off-Line Quasi-Resonant Switching Regulators

Typical Application

Not to scale

Package: 7-Pin TO-3P

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