SG1846J

Overview

The SG1846J is a high-reliability current mode PWM controller manufactured by Microchip Technology. It operates within an input voltage range of 8V to 40V and supports junction temperatures from -55°C to 125°C. The device features dual sink/source outputs, a typical rise time of 50 ns, and a switching frequency capability up to 500kHz with a peak output drive current of 100mA. Packaged in a 16-pin CDIP tube, it includes automatic feed-forward compensation, programmable pulse-by-pulse current limiting, and automatic symmetry correction for push-pull configurations.

Feature Summary

• Dual sink/source output configuration for versatile driver interfacing
• Automatic symmetry correction specifically designed for push-pull topologies
• Programmable pulse-by-pulse current limiting for enhanced protection
• Automatic feed-forward compensation for improved line regulation

Applications

• High-reliability isolated switching regulators
• Military and aerospace power supply systems
• Push-pull converter applications requiring symmetry correction
• Current mode PWM control circuits

Procurement Notes

Verify the specific ordering suffix and environmental qualification status when sourcing this component. Confirm that the package type matches the required 16-pin CDIP specification. Ensure compatibility with the intended operating temperature range of -55°C to 125°C. Check for any non-rohs designator or special handling requirements associated with the specific batch. Validate the manufacturer source against authorized distributors to guarantee authenticity.

Selection Notes

Select the SG1846J when designing for high-reliability environments requiring current mode PWM control. Consider its dual sink/source outputs for driving external power stages directly. Evaluate the need for automatic symmetry correction if utilizing a push-pull transformer configuration. Assess the thermal requirements against the specified -55°C to 125°C operating range. Verify that the 500kHz frequency capability aligns with the system's switching speed requirements.

Part Context

This component belongs to the SG1846 family of current mode PWM controllers. It shares functional similarities with other industry-standard controllers but is distinguished by its high-reliability construction and specific military-grade options. The SG1846J variant provides a robust solution for demanding applications where long-term stability and precise current limiting are critical performance factors.

Replacement Considerations

Public confirmed substitute part numbers include UC3846AJ and UC1846AJ. These alternatives offer similar current mode PWM functionality but may differ in package style or specific reliability qualifications. Verify pinout compatibility and electrical parameter alignment before substitution.