NC-Cap/PSR-VTM (Primary Side Regulation) CV/CC Power Switch
EATURES
◆ Built-in 800V Power BJT and start resistance
◆ Proprietary NC-Cap/PSR-VTM Control:
● ±5% CC and CV Precision
● Proprietary “Audio Noise Cancellation” Control
● Built-in “Fast Dynamic Response” Control to Meet USB Charge Requirements
● Proprietary “Zero-Output Startup” Control
● Proprietary “Smart Output Short Protection”
● without External Compensation/Filtering Capacitor Needed
◆ Direct Drive of Low Cost BJT
◆ Double winding transformer scheme to optimize system cost
◆ Proprietary Cable Drop Compensation
◆ Multi Mode Control
◆ Cycle-by-Cycle Current Limiting
◆ Leading Edge Blanking (LEB)
◆ Built-in Soft Start, Pin Floating Protection
◆ VDD UVLO, Clamp
APPLICATIONS
◆ Battery chargers
◆ Replaces linear transformer and RCC SMPS
◆ Small power adapter
◆ AC/DC LED lighting
GENERAL DESCRIPTION
SF1152 is a high precision, highly integrated DCM (Discontinuous Conduction Mode) Self powered Primary Side Regulation (PSR) power switch for offline small power converter applications. It has built-in power BJT, which can further lower system cost.
SF1152 has built-in proprietary NC-Cap/PSR-VTM control for CV control, which eliminates external compensation or filtering capacitor. It has built-in cable drop compensation function, which can provide excellent CV performance. The IC uses Multi Mode Control to improve efficiency and reliability and to decrease audio noise energy @ light loadings.
SF1152 integrates proprietary “Audio Noise Cancellation” control for audio noise free operation. The IC has built-in “Fast Dynamic Response” control to meet USB Charge requirements. SF1152 also integrates proprietary “Zero-Output Startup” control to achieve startup when output is near zero voltage. The IC has proprietary “Smart Output Short Protection”, which can protect the system with large leakage inductance when output is short circuit.
SF1152 integrates functions and protections of FB Short Protection, Under Voltage Lockout (UVLO), Soft Start, Cycle-by-cycle Current Limiting (OCP), Pin Floating Protection, VDD Clamping.
SF1152 is available SOP7 packages
