MMTL431AR

Overview

The MMTL431AR is an adjustable precision diode shunt regulator manufactured by Diotec Semiconductor in a SOT-23 (TO-236) package. It features a reference voltage of 2.495 V with a narrow tolerance band of ±0.5%. The device operates within a cathode voltage range of VREF to 36 V and supports a cathode current from 1 mA to 100 mA. It exhibits low dynamic output impedance of approximately 0.15 Ω and temperature drift of up to 6 mV across the commercial/industrial operating range of -25°C to +85°C.

Feature Summary

• Temperature compensated for stable operation across varying thermal conditions
• Reverse pinning configuration available in the R version variant
• Low output impedance ensuring precise regulation performance
• Narrow voltage tolerance band for high accuracy applications

Applications

• Precision voltage reference for voltage regulators and comparators
• Replacement for low voltage Zener diodes requiring tighter tolerances
• Low component count power supplies for microcontrollers
• Secondary side control and regulation for flyback converters

Procurement Notes

Verify the specific suffix designation when ordering, as the base model denotes standard commercial grade while suffixes indicate automotive compliance levels. Confirm that the selected variant meets the required reliability standards for the intended application environment. Ensure compatibility with surface mount assembly processes and verify storage temperature limits during handling.

Selection Notes

Select this component for circuits requiring a programmable shunt regulator with tight initial voltage accuracy. Consider the reverse pinning feature if PCB layout constraints require inverted terminal orientation compared to standard TO-236 packages. Evaluate the minimum regulation current requirements against the specific A or B version characteristics to ensure stable operation at low load currents.

Part Context

This part belongs to the MMTL431A/B series of adjustable precision diode shunt regulators. It serves as a direct functional replacement for fixed low-voltage Zener diodes where adjustable output and superior linearity are required. The device integrates internal temperature compensation to maintain reference stability without external components.

Replacement Considerations

Direct substitutes include the MMTL431A for standard commercial grade applications. For automotive-grade requirements, consider the MMTL431AR-AQ which holds AEC-Q100 qualification. Verify pinout compatibility if replacing non-Diotec equivalents due to potential variations in lead frame configurations.