General Description
In order to enhance the efficiency performance, the
LD5523D2 integrates the multi-mode PWM controller, which
consists of Quasi-Resonant (QR) PWM control for light load
condition and Continue Conduction Mode (CCM) for heavy
load condition. Moreover, the QR controller gains the system
performance, but also brings the worse EMI capability,
especially at boundary mode in heavy load. While the
frequency swapping function of LD5523D2 can reduce the
EMI emission of SMPS and helps the power circuit designers
to simply deal with EMI filter and saves several component
and developing time.
The LD5523D2 is implemented in SOT-26 package, and
includes the comprehensive protection function, such as
Over Load Protection (OLP), Over Voltage Protection (OVP),
Output Short Circuit Protection (OSCP) and adjustable Over
Temperature Protection (CS_OTP). Furthermore, the
programmable brown-in/out protection is built-in.

Features
 PSR CCM+QR Multi-Mode Control.
 Frequency Swapping for better EMI performance
 Low Startup Current (<1.5A)
 Built-in load regulation compensation
 65 kHz PWM switching frequency.
 Current mode control with cycle-by-cycle current limit
 UVLO (Under Voltage Lock Out)
 LEB (Leading-Edge Blanking) on CS pin
 VCC & FB Over Voltage Protection
 Adjustable Brown in/out on FB pin.
 External OTP (Over Temperature Protection) on CS Pin
 Internal OTP (Over Temperature Protection)
 Gate Source/Sink Capability: 40mA/-170mA @ output
pin with 1nF capacitor.

Applications
 Networking power supply
 Lower Power AC/DC Adaptor