TL431IDMR2

Overview

The TL431IDMR2 is a three-terminal programmable shunt regulator diode from onsemi, housed in an 8-lead Micro8 package. It operates as a low temperature coefficient zener, providing a reference voltage adjustable from the internal 2.5V up to 36V using two external resistors. The device supports a cathode current range of 1.0 mA to 100 mA with a typical dynamic impedance of 0.22 ohms. It features a reference input voltage tolerance of ±2.2% and an equivalent full-range temperature coefficient of 50 ppm/°C. Designed for industrial applications, it functions over an ambient temperature range of -40°C to +85°C.

Feature Summary

• Programmable output voltage capability extending from the internal reference up to 36 V
• Temperature compensated operation across the full rated industrial ambient temperature range
• Low dynamic output impedance ensuring stable regulation under varying load conditions
• Internal 2.5 V reference allows convenient generation of stable voltages from standard logic supplies

Applications

• Feedback control circuits driving optocouplers in switching power supplies
• Digital voltmeters requiring precise voltage references
• Op amp circuitry utilizing the device as a positive or negative voltage reference
• Constant current sources and sinks for LED drivers or battery testing

Procurement Notes

Verify that the ordering suffix matches the required package type and shipping configuration. Confirm the specific tolerance grade corresponds to the design requirements. Check RoHS compliance status if restricted substances are prohibited. Ensure the operating temperature range meets the environmental constraints of the target application. Validate pinout compatibility during PCB layout integration.

Selection Notes

Select this component when a precision adjustable shunt regulator is needed within the industrial temperature range. Consider the Micro8 package dimensions for space-constrained surface mount designs. Evaluate stability boundary conditions regarding load capacitance and cathode current to ensure loop stability. Compare initial accuracy against other series grades if tighter tolerances are required.

Part Context

This device belongs to the TL431 family of programmable precision references manufactured by onsemi. It serves as a monolithic replacement for traditional Zener diodes in various analog and power management applications. The family includes variants with different tolerances and extended temperature ranges, such as the NCV prefix for automotive use.

Replacement Considerations

TL431IDMR2G is the lead-free version of this component. NCV431AIDMR2 offers automotive qualification with similar electrical characteristics. TL431CDMR2 provides a wider initial tolerance range. Verify pinout and thermal performance when substituting with packages from other manufacturers.