NCP1256BSN100T1G

AC DC Converters, Offline Switchers Overview

The NCP1256BSN100T1G is a low-power offline PWM current-mode controller designed for flyback topologies. It operates with a fixed switching frequency of 100 kHz and supports a maximum duty cycle of 84%. The device functions within an operating supply voltage range of 8.9 V to 35 V, delivering up to 500 mA output current. It features a TSOP-6 surface-mount package and withstands temperatures from -40°C to +125°C.

AC DC Converters, Offline Switchers Feature Summary

• Implements peak current-mode control with jittered switching circuitry to reduce electromagnetic interference.
• Provides adjustable over-power protection that disables at low line conditions to prevent overload.
• Supports frequency foldback down to 26 kHz and skip-cycle operation during light load conditions.
• Includes timer-based auto-recovery short-circuit protection and adjustable brown-out levels.

AC DC Converters, Offline Switchers Applications

• Cost-effective switch mode power supplies
• Adapters for consumer electronics
• Chargers for portable devices

AC DC Converters, Offline Switchers Procurement Notes

Verify the specific suffix 'BSN100' confirms the 100 kHz fixed frequency variant against the manufacturer datasheet. Ensure the TSOP-6 package matches the target PCB footprint. Confirm RoHS compliance status if required by regional regulations. Validate the operating temperature range aligns with the intended environmental conditions.

AC DC Converters, Offline Switchers Selection Notes

Select this component for designs requiring low standby power through frequency foldback and skip-cycle modes. The integrated brown-out protection simplifies input voltage monitoring requirements. Consider the 100 kHz switching frequency for balancing efficiency and component size in flyback applications.

AC DC Converters, Offline Switchers Part Context

This part belongs to the NCP1256 series of low-power offline controllers. It shares functional similarities with other variants like the NCP1256ASN65T1G, differing primarily in the fixed switching frequency setting. The series targets compact power supply designs where cost and performance are critical.

AC DC Converters, Offline Switchers Replacement Considerations

The NCP1256ASN65T1G serves as a direct substitute offering identical functionality with a 65 kHz fixed frequency instead of 100 kHz. Verify transformer design compatibility when swapping between these frequency variants.

AC DC Converters, Offline Switchers FAQ

How does the controller manage efficiency under light loads?

It automatically folds back the switching frequency down to 26 kHz and enters skip-cycle mode while freezing the peak current to minimize losses.

What protection mechanisms are included for fault conditions?

The device features timer-based auto-recovery short-circuit protection, lossless over-power protection, and latchable inputs for OVP and OTP events.