Texas Instruments LM3724IM5-2.32/NOPB

Overview

LM3724IM5-2.32/NOPB from Texas Instruments is an active-low open-drain microprocessor reset supervisor IC designed for 2.5V supply monitoring. It asserts reset when VCC falls below 2.32V ±10mV, guarantees valid output down to VCC ≥1V, delivers 190ms typical reset timeout, and draws only 6µA typical supply current at 2.5V. It is used in battery-powered embedded systems requiring reliable power-on initialization and brownout protection.

For engineers reviewing the LM3724IM5-2.32/NOPB datasheet, LM3724IM5-2.32/NOPB pinout, LM3724IM5-2.32/NOPB application, or LM3724IM5-2.32/NOPB equivalent, key selection considerations include its 2.32V reset threshold, open-drain output architecture, SOT-23-5 package, −40°C to +85°C industrial temperature range, and compatibility with manual reset (MR) debouncing and multi-supervisor wire-OR configurations.

Technical Context

The LM3724IM5-2.32/NOPB integrates a precision voltage reference (1.225V), low-line comparator, manual reset comparator, and one-shot timer. Its open-drain RESET output enables direct wire-OR connection with other supervisors or logic families without level-shifting.

It features built-in MR glitch immunity (100ns), 22kΩ internal MR pull-up, and transient rejection optimized for short negative-going VCC excursions - maintaining reset assertion only when overdrive exceeds defined thresholds per Figure 14 of SNVS154E.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.9mm × 1.6mm × 1.45mm body, gull-wing leads, RoHS-compliant matte tin lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor reset applications.

Compared with TPS3808G125DBVR and MAX809SEUR+T, the LM3724IM5-2.32/NOPB uniquely combines precise 2.32V threshold matching for 2.5V rails, open-drain output for flexible bus interfacing, integrated MR debouncing, and industrial temperature rating - making it optimal for robust, multi-supervisor embedded systems where timing accuracy and signal integrity are critical.

Availability

LM3724IM5-2.32/NOPB is available at Aetrix Electronics and suitable for industrial PLCs, battery-powered medical wearables, automotive body control modules, and IoT edge sensors requiring stable component supply across extended lifecycle programs.

Supply support for LM3724IM5-2.32/NOPB includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The LM372x family was designed specifically for high-reliability microprocessor reset supervision in space-constrained, low-power embedded systems - emphasizing precision threshold accuracy, guaranteed reset timing, and robust noise immunity.

FAQ

What is the exact reset threshold voltage of the LM3724IM5-2.32/NOPB?

The LM3724IM5-2.32/NOPB has a factory-programmed reset threshold of 2.32V with a tolerance of ±10mV over the full industrial temperature range (−40°C to +85°C). This value is specified in the Electrical Characteristics table of SNVS154E and applies directly to the LM3724IM5-2.32/NOPB variant. It is optimized for monitoring nominal 2.5V power rails within a 90.8–94.8% voltage window.

Does the LM3724IM5-2.32/NOPB require an external pull-up resistor on the RESET pin?

Yes, the LM3724IM5-2.32/NOPB features an active-low open-drain RESET output and requires an external pull-up resistor to define the logic-high voltage level. The datasheet recommends a 100kΩ resistor for general use, though values must be selected based on sink current requirements and bus capacitance. No pull-up is integrated internally on the RESET pin - only on the MR pin.

Can the LM3724IM5-2.32/NOPB operate reliably below 1.0V VCC?

No - the LM3724IM5-2.32/NOPB guarantees valid RESET output only for VCC ≥1.0V, as stated in the Electrical Characteristics table. Below 1.0V, the internal comparators and timer cease functioning, and RESET becomes indeterminate. For systems requiring reset assertion down to 0V, TI recommends adding a 100kΩ pull-down resistor from RESET to GND, as described in Application Information section "ENSURING A VALID RESET OUTPUT DOWN TO VCC = 0V".

How does the manual reset (MR) function work on the LM3724IM5-2.32/NOPB?

The MR pin on the LM3724IM5-2.32/NOPB is an active-low input with an internal 22kΩ pull-up resistor. When pulled below 0.25×VCC for longer than 10µs, it triggers a full 190ms reset pulse. Glitches shorter than 100ns are rejected. The MR pin may be left unconnected (floating), in which case the internal pull-up holds it high and disables manual reset functionality.

Is the LM3724IM5-2.32/NOPB pin-compatible with other devices in the LM372x family?

Yes - all LM372x variants including LM3722, LM3723, and LM3724 share identical SOT-23-5 pinouts and footprints. The LM3724IM5-2.32/NOPB uses pins 1(GND), 2(GND), 3(RESET), 4(MR), and 5(VCC) as defined in the Connection Diagram (Figure 3) of SNVS154E. This allows direct substitution within the same family when reset polarity and threshold match design requirements.