SF5565M
η-BalanceTM Current Mode PWM Controller with Brownout Protection
FEATURES
◆ Less than 100mW Standby Power
◆ Brownout Protection (BOP)
◆ Proprietary η-BalanceTM Control to Boost
Light Load Efficiency
◆ Proprietary “Zero OCP/OPP Recovery Gap”
Control
◆ Proprietary “Audio Noise Free OCP
Compensation”
◆ Fixed 65KHz Switching Frequency
◆ Built-in Frequency Shuffling
◆ Built-in Soft Start Function
◆ Frequency Reduction and Burst Mode Control
for Energy Saving
◆ Built-in Synchronous Slope Compensation
◆ Cycle-by-Cycle Current Limiting
◆ Built-in Leading Edge Blanking (LEB)
◆ Current Mode Control
◆ Pin Floating Protection
◆ Latch Plug-off Protection
◆ VDD UVLO, OVP & Clamp
APPLICATIONS
Offline AC/DC Flyback Converter for
◆ AC/DC Adaptors
◆ Open-frame SMPS
TYPICAL APPLICATION
GENERAL DESCRIPTION
SF5565M is a high performance, high efficiency,
highly integrated current mode PWM controller for
offline flyback converter applications.
In SF5565M, PWM switching frequency with shuffling
is fixed to 65KHz and is trimmed to tight range. When
the output power demands decrease, the IC
decreases switching frequency based on the
proprietary η -BalanceTM control to boost power
conversion efficiency at the light load. When output
power falls below a given value, the IC enters into
burst mode and can achieve less than 100mW no
load power.
The IC can achieve “Zero OCP/OPP Recovery Gap”
using SiFirst’s proprietary control algorithm.
SF5565M also has built in proprietary “Audio Noise
Free OCP Compensation”, which can achieve
constant power limiting and can achieve audio noise
operation at heavy loading when line input is around
90VAC.
SF5565M integrates functions and protections of
Brownout Protection (BOP), Under Voltage Lockout
(UVLO), VDD Over Voltage Protection (OVP), Cycle-
by-cycle Current Limiting (OCP), Over Load
Protection (OLP), Gate Clamping, VDD Clamping,
Leading Edge Blanking (LEB), Soft Start, Pins
Floating Protection, etc.
In SF5565M, VDD OVP is latch plug-off protection,
the other protections are auto-recovery mode.
SF5565M is available in SOT23-6 package.
AC IN
65
GATE VDD
4
CS
SF5565M
GND FB BO
1 23
DC Out
TL431
©SiFirst Technology
- 1 - Confidential
SiFirst_DS_5565M_V1.0
