NCP432BISNT1G

Overview

The NCP432BISNT1G is a three-terminal programmable shunt regulator diode from onsemi, operating as a low temperature coefficient Zener reference. It features a typical voltage reference tolerance of ±0.5% at 25°C and an equivalent full-range temperature coefficient of 50 ppm/°C. The device supports a cathode current range of 40 µA to 100 mA with a maximum cathode-to-anode voltage of 36 V. It operates within an ambient temperature range of -40°C to +85°C and is housed in a surface-mount SOT-23-3 package.

Feature Summary

• Programmable output voltage adjustable from the internal 2.5 V reference up to 36 V using two external resistors
• Low minimum operating current capability for efficient secondary regulation in switching power supplies
• Temperature compensated operation across the full rated industrial temperature range

Applications

• Voltage adapters
• Switching power supply feedback control
• Precision voltage reference circuits
• Battery chargers
• Instrumentation systems

Procurement Notes

Verify the specific suffix ISNT1G corresponds to the required -40°C to +85°C temperature grade and 0.5% tolerance. Confirm the SOT-23-3 package orientation matches the schematic pinout (Pin 1: Cathode). Ensure the design accounts for the recommended operating conditions regarding continuous cathode current limits and thermal dissipation constraints.

Selection Notes

Select this component when a precision shunt regulator with low bias current is required for secondary side feedback loops. The NCP432B variant offers tighter initial accuracy compared to standard A-grade devices. Consider the dynamic impedance characteristics for stability analysis when driving capacitive loads or optocouplers in isolated converter topologies.

Part Context

This device belongs to the NCP431/NCP432 series of programmable precision references. It serves as a direct functional replacement for traditional Zener diodes in applications requiring higher accuracy and lower temperature drift. The NCP432B designation specifically indicates the B-grade tolerance level within the broader family of adjustable shunt regulators.

Replacement Considerations

NCP431BISNT1G

FAQ

How is the output voltage programmed?

The output voltage is set between the internal 2.5 V reference and 36 V by connecting two external resistors in a voltage divider configuration between the cathode and reference input pins.

What is the minimum cathode current required for regulation?

The device requires a minimum cathode current of 40 µA to maintain stable regulation and proper loop gain.