R1225N182J-TR-FE

Overview

The R1225N182J-TR-FE is a PWM/VFM step-down DC/DC controller manufactured by Nisshinbo Micro Devices. It operates with an input voltage range of 2.3 V to 18.5 V and features a fixed output voltage of 1.8 V. The device supports a switching frequency of 180 kHz and delivers a maximum duty cycle of 100%. It is housed in a SOT-23W-6 surface-mount package and functions within a temperature range of -40°C to +85°C.

Feature Summary

• Integrates Pulse Width Modulation (PWM) and Variable Frequency Mode (VFM) control for optimized efficiency across varying load conditions.
• Supports a wide input voltage range from 2.3 V to 18.5 V, accommodating diverse power supply sources.
• Features a fixed 1.8 V output voltage setting, simplifying external component selection for standard logic levels.

Applications

• Portable electronic devices requiring efficient step-down conversion
• Battery-powered systems utilizing lithium-ion or lithium-polymer cells
• Embedded circuits needing stable 1.8 V logic supply rails

Procurement Notes

Verify the specific suffix 'J' corresponds to the required output voltage tolerance and marking code before ordering. Confirm that the SOT-23W-6 package dimensions align with the target PCB footprint. Ensure the operating temperature range meets the environmental requirements of the final assembly. Cross-reference the datasheet revision date to confirm current electrical specifications.

Selection Notes

Select this component when a fixed 1.8 V output is required without external feedback resistors. The 180 kHz frequency allows for smaller passive components compared to lower-frequency alternatives. Consider the non-synchronous design if cost reduction is prioritized over peak efficiency at light loads. Verify input voltage stability remains above the minimum threshold during transient events.

Part Context

This part belongs to the R1225N series of switching controllers from Nisshinbo Micro Devices. The series focuses on compact, low-cost solutions for general-purpose power management. The R1225N182J variant specifically targets applications requiring a fixed 1.8 V output. It complements other variants in the family that offer different fixed output voltages.

Replacement Considerations

Direct substitutes include other R1225N series parts with identical pinouts but different output voltages, such as R1225N182B or R1225N182K, provided the voltage requirement changes. Verify compatibility with existing inductor and capacitor values when swapping between fixed-voltage variants within the same series.

FAQ

Does the R1225N182J-TR-FE support synchronous rectification?

No, the R1225N182J-TR-FE is a non-synchronous controller that requires an external high-side and low-side MOSFET configuration.

What is the maximum duty cycle of this controller?

The device supports a maximum duty cycle of 100%, allowing the output voltage to track the input voltage closely under low dropout conditions.