POWER AND LINEAR IC SOLUTIONS

Switching Converters Optimise Power and EMI Performance in Flyback Designs

Fairchild Semiconductor’s Green FPS e-Series is a new family of Fairchild Power Switch (FPS™) switching converters that offer high efficiency and low ElectroMagnetic Interference (EMI). They are particularly suitable for achieving high system reliability in DVD player, Set Top Box, LCD monitor and other 25W, and lower power, power supply designs.



Based on Fairchild’s proprietary valley switching technique, the Green FPS products raise power conversion efficiency by 1% and reduce EMI by up to 5dB compared to conventional hard-switched converter topologies. In burst-mode operation, the devices can attain no-load standby power consumption of below 0.2W and below 1W with a 0.5W load.

The converters combine a fully avalanche rated SenseFET, a current mode Pulse Width Modulation (PWM) controller and various protection functions, simplifying design and improving system reliability. The PWM controller includes an integrated fixed-frequency oscillator, UnderVoltage LockOut (UVLO), Leading Edge Blanking (LEB), optimised gate driver, internal soft-start, temperature compensated precise current sources for loop compensation, and self-protection circuitry. This combination offers designers the system cost, component count, reliability, size and weight advantages of PWM IC and MOSFET integration, together with high energy efficiency and reliability, in an all-in-one solution.

Well suited to cost effective designs of valley switching fly-back converters, the Green FPS e-Series allows power converters to operate with narrow frequency variation while maintaining valley switching operation. Valley switching operation enables the MOSFET to turn on with minimum drain voltage and offers inherent frequency modulation resulting in a dramatic reduction in EMI noise. This mode of operation also enables soft switching, with resultant efficiency improvements.

Supplied in space saving eight-lead DIP or LSOP packaging, the devices integrate OverVoltage Protection (OVP), OverLoad protection (OLP), abnormal over-current protection (AOCP) and Thermal ShutDown (TSD).

Product Specification Table

Products	VDS Max (V)	RDS(ON) Max (Ω)	Peak Current Limit (A)	Output Power Max @85-265VAC (W)	Output Power Max @230VAC (W)	Package
FSQ0165RN	650	10	0.9	13	15	8DIP/8LSOP
FSQ0265RN	650	6	1.2	16	20	8DIP/8LSOP
FSQ0365RN	650	4.5	1.5	19	25	8DIP/8LSOP
FSQ311	650	19	0.6	8	10	8DIP/8LSOP
FSQ321	650	19	0.6	10	12	8DIP/8LSOP

Features

• Integrated switching converters
• Low EMI: 5dB below conventional solutions
• High efficiency: 1% above conventional solutions
• 0.2W standby power (no load)
• Pulse-by-pulse current limit
• Integrated protection
  • OverLoad Protection (OLP)
  • OverVoltage Protection (OVP)
  • Abnormal OverCurrent Protection (AOCP)
  • Internal Thermal ShutDown (TSD)
  • UnderVoltage LockOut (UVLO) with hysteresis
• Built-in soft-start (15ms)

Applications

• Power supply for DVD players and recorders
• Set-top boxes
• Mains adaptors
• PCs
• LCD TVs
• PDP TVs

For further information, including a copy of the Application Notes, please click here