UCC28750 Series

Current-mode flyback controller with secondary-side regulation (SSR) for offline applications

Catalog

Current-mode flyback controller with secondary-side regulation (SSR) for offline applications

Part	Topology	Supplier Device Package	Duty Cycle	Control Features	Operating Temperature [Min]	Operating Temperature [Max]	Package / Case	Voltage - Supply (Vcc/Vdd) [Min]	Voltage - Supply (Vcc/Vdd) [Max]	Output Isolation	Mounting Type	Voltage - Start Up	Frequency - Switching	Fault Protection
Texas Instruments UCC287506DBVR
Texas Instruments UCC287504DBVR
Texas Instruments UCC287503DBVR
Texas Instruments UCC287508DBVR
Texas Instruments UCC287505DBVR	Flyback Secondary Side SR	SOT-23-6	80 %	Soft Start	-40 °C	125 ¯C	SOT-23-6	10 V	26 V	Isolated	Surface Mount	15.3 V	100 kHz	Current Limiting Over Power Over Temperature Over Voltage Short Circuit
Texas Instruments UCC287507DBVR	Flyback Secondary Side SR	SOT-23-6	80 %	Soft Start	-40 °C	125 ¯C	SOT-23-6	10 V	26 V	Isolated	Surface Mount	15.3 V	100 kHz	Current Limiting Over Power Over Temperature Over Voltage Short Circuit
Texas Instruments UCC287501DBVR

Catalog

Current-mode flyback controller with secondary-side regulation (SSR) for offline applications

Key Features

• Stable continuous conduction mode (CCM) operation with internal slope compensationFixed-frequency operation of 65kHz or 100kHzSecondary-side regulation (SSR) with opto-couplerFrequency foldback and burst mode for improved light-load efficiencyFrequency dithering for improved EMI performanceGate source/sink capability: 300mA/500mAInternal 4ms soft-startRobust protection features:Over-voltage and Under-voltage lockoutOutput over-power protection (OPP)Output short-circuit (OSC) protectionOutput over-voltage (OVP) protectionCycle-by-cycle peak over-current limitExternal over-temperature, over-voltage protection (OTP, OVP) and brownout detection on FLT pinInternal thermal shutdownStable continuous conduction mode (CCM) operation with internal slope compensationFixed-frequency operation of 65kHz or 100kHzSecondary-side regulation (SSR) with opto-couplerFrequency foldback and burst mode for improved light-load efficiencyFrequency dithering for improved EMI performanceGate source/sink capability: 300mA/500mAInternal 4ms soft-startRobust protection features:Over-voltage and Under-voltage lockoutOutput over-power protection (OPP)Output short-circuit (OSC) protectionOutput over-voltage (OVP) protectionCycle-by-cycle peak over-current limitExternal over-temperature, over-voltage protection (OTP, OVP) and brownout detection on FLT pinInternal thermal shutdown

Description

UCC28750 is a highly-integrated current-mode, continuous-conduction-capable, PWM controller optimized for high performance, low standby power, and cost effective offline flyback converter applications using an opto-coupler. During light-load conditions the device enters frequency foldback and burst modes, improving light-load efficiency. The burst-mode algorithm used in UCC28750 controls the minimum effective switching frequency to prevent audible noise during light-load conditions. Frequency dithering improves EMI performance, and is active in normal, frequency foldback, and power boost operations. UCC28750 provides protection features that enable a robust converter design with minimal external components. Output over-power protection (OPP) and cycle-by-cycle over-current limit protect the load and power-stage components from electrical stress. Over-voltage and under-voltage lockout (OVLO and UVLO) prevent switching in unwanted input conditions. The FLT pin provides line brown-out sensing and protection, or external over-temperature and over-voltage protection, depending on the device variant. The FLT pin is also used to disable the device through external control by pulling the pin to ground, regardless of the device variant. UCC28750 is a highly-integrated current-mode, continuous-conduction-capable, PWM controller optimized for high performance, low standby power, and cost effective offline flyback converter applications using an opto-coupler. During light-load conditions the device enters frequency foldback and burst modes, improving light-load efficiency. The burst-mode algorithm used in UCC28750 controls the minimum effective switching frequency to prevent audible noise during light-load conditions. Frequency dithering improves EMI performance, and is active in normal, frequency foldback, and power boost operations. UCC28750 provides protection features that enable a robust converter design with minimal external components. Output over-power protection (OPP) and cycle-by-cycle over-current limit protect the load and power-stage components from electrical stress. Over-voltage and under-voltage lockout (OVLO and UVLO) prevent switching in unwanted input conditions. The FLT pin provides line brown-out sensing and protection, or external over-temperature and over-voltage protection, depending on the device variant. The FLT pin is also used to disable the device through external control by pulling the pin to ground, regardless of the device variant.