NCP1256ESN65T1G

AC DC Converters, Offline Switchers Overview

The NCP1256ESN65T1G is a low-power offline PWM current-mode controller manufactured by onsemi, designed for flyback converter topologies. It operates within a supply voltage range of 8.9 V to 35 V and features a fixed switching frequency of 65 kHz with an internal jitter circuit to optimize EMI performance. The device supports a maximum duty cycle of 83% and includes integrated protection mechanisms such as over-power protection (OPP), under-voltage lockout (UVLO), and timer-based auto-recovery short-circuit protection. It is housed in a compact TSOP-6 surface-mount package and functions reliably across an operating temperature range from -40°C to +125°C.

AC DC Converters, Offline Switchers Feature Summary

• Integrates a 65 kHz switching frequency with an internal jitter circuit to reduce electromagnetic interference emissions.
• Features adjustable over-power protection (OPP) that limits output power at high input voltages while maintaining low standby consumption.
• Includes a timer-based auto-recovery short-circuit protection mechanism to prevent thermal runaway during fault conditions.
• Supports frequency foldback and skip-cycle modes to enhance efficiency during light-load or no-load operation.

AC DC Converters, Offline Switchers Applications

• Low-power AC-DC adapters for consumer electronics
• Standby power supplies for televisions and monitors
• Battery chargers for mobile devices
• Offline power supplies for appliances

AC DC Converters, Offline Switchers Procurement Notes

Verify the specific suffix 'ESN65' against the official datasheet to confirm pinout compatibility and electrical characteristics relative to other variants like 'ASN65'. Ensure the component meets RoHS directives if required for your assembly process. Confirm the package type is TSOP-6 and check for moisture sensitivity level requirements prior to soldering. Cross-reference the manufacturer part number with authorized distributors to avoid counterfeit components.

AC DC Converters, Offline Switchers Selection Notes

Select this controller for designs requiring a balance between low standby power and robust protection features in small form factors. It is suitable for applications where EMI reduction is critical due to the integrated jitter function. Consider the 65 kHz frequency for standard transformer sizes. Evaluate the need for its specific OPP implementation versus simpler current-limiting schemes based on system safety requirements.

AC DC Converters, Offline Switchers Part Context

This component belongs to the NCP125x series of current-mode PWM controllers from onsemi, which are engineered for cost-effective and high-performance offline power supplies. The series is characterized by its ability to operate with minimal external components while providing comprehensive protection features. It targets the market segment for energy-efficient power adapters and standalone converters.

AC DC Converters, Offline Switchers Replacement Considerations

Check for NCP1256ASN65T1G as a potential variant within the same family, ensuring functional equivalence regarding pinout and specifications before substitution.