Texas Instruments LM3722IM5-4.63/NOPB

Overview

LM3722IM5-4.63/NOPB from Texas Instruments is a precision 5-pin SOT-23 microprocessor reset supervisor IC with active-low push-pull RESET output, factory-trimmed 4.63 V reset threshold (±1.5% over −40°C to +85°C), 190 ms typical reset timeout, guaranteed operation down to VCC ≥1 V, and 6 µA typical supply current. It monitors 5 V supply rails in embedded controllers and industrial microprocessor systems.

For engineers reviewing the LM3722IM5-4.63/NOPB datasheet, LM3722IM5-4.63/NOPB pinout, LM3722IM5-4.63/NOPB application, or LM3722IM5-4.63/NOPB equivalent, key selection criteria include reset threshold accuracy, temperature stability (30 ppm/°C tempco), MR input debounce timing (2 µs propagation), open-drain compatibility via external pull-up, and guaranteed reset validity at low VCC for brownout recovery.

Technical Context

The LM3722IM5-4.63/NOPB integrates a precision bandgap reference (1.225 V), dual comparators (reset and manual reset), and a one-shot timer to generate a minimum 100 ms (190 ms typical) active-low reset pulse after VCC rises above 4.63 V or MR is released. Its internal 22 kΩ MR pull-up enables direct switch interfacing without external components.

It operates across −40°C to +85°C (industrial grade), supports VCC from 1.0 V to 5.5 V, and features glitch immunity on both VCC (≥100 ns rejection) and MR inputs. The active-low push-pull output drives loads up to 3.2 mA at VCC = 4.63 V while maintaining VOL ≤ 0.4 V.

Key Specifications

Pinout & Package

LM3722IM5-4.63/NOPB uses the industry-standard 5-pin SOT-23 (DBV) package, 2.9 mm × 1.6 mm × 1.1 mm, RoHS-compliant, green (Pb-free, no Sb/Br), moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM3722IM5-4.63/NOPB, MAX811TEUS+T requires external pull-up and offers shorter timeout, while TPS3808G33DBVR targets 3.3 V systems and lacks factory-trimmed 4.63 V accuracy-neither provides identical functionality or pinout compatibility.

Availability

LM3722IM5-4.63/NOPB is available at Aetrix Electronics and suitable for industrial PLC controllers, embedded medical monitors, point-of-sale terminals, smart energy meters, and battery-powered instrumentation requiring stable component supply across extended temperature ranges.

Supply support for LM3722IM5-4.63/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 leader specializing in analog, embedded processing, and power management technologies, with decades of experience in high-reliability supervisory circuits.

The LM3722IM5-4.63/NOPB belongs to TI's microprocessor supervisory IC product line, designed specifically for robust power-on reset, brownout detection, and manual reset functionality in cost-sensitive industrial and portable electronics.

FAQ

What is the exact reset threshold voltage of LM3722IM5-4.63/NOPB and how tightly is it specified?

The LM3722IM5-4.63/NOPB has a factory-trimmed reset threshold of 4.63 V, specified as 4.54 V (min) to 4.72 V (max) over the full industrial temperature range (−40°C to +85°C), corresponding to ±1.5% tolerance. This tight specification ensures reliable detection of 5 V supply brownouts at 92.6–94.4% of nominal voltage without external calibration. The LM3722IM5-4.63/NOPB achieves this via laser-trimmed internal resistors referenced to a 1.225 V bandgap.

Does LM3722IM5-4.63/NOPB support manual reset functionality, and what are the interface requirements?

Yes, LM3722IM5-4.63/NOPB includes a dedicated MR (Manual Reset) input pin with an internal 22 kΩ pull-up to VCC, enabling direct connection to a momentary switch tied to GND. The MR pin is fully debounced: it asserts reset within 2 µs of being pulled below VIH (0.7×VCC) and requires a minimum 10 µs low pulse. No external components are needed, making LM3722IM5-4.63/NOPB ideal for compact front-panel reset implementations.

What is the guaranteed minimum reset pulse width for LM3722IM5-4.63/NOPB, and how does it behave during power-up?

The LM3722IM5-4.63/NOPB guarantees a minimum reset pulse width of 100 ms, with a typical value of 190 ms. During power-up, RESET remains low until VCC rises above 4.63 V and then stays asserted for the full timeout period-even if VCC remains stable-ensuring the microprocessor completes its internal initialization sequence. This behavior is implemented via an internal one-shot timer, independent of VCC slew rate.

Can LM3722IM5-4.63/NOPB operate reliably at very low supply voltages, and what is its minimum functional VCC?

Yes, LM3722IM5-4.63/NOPB guarantees valid RESET output operation down to VCC = 1.0 V, as confirmed in the Electrical Characteristics table. Below 1 V, the output may not sink rated current, but above 1 V, VOL remains ≤0.4 V at 3.2 mA sink load. This capability allows LM3722IM5-4.63/NOPB to maintain system integrity during deep brownout recovery and supports graceful shutdown sequences in battery-powered devices.

How does LM3722IM5-4.63/NOPB handle power supply transients, and what is its immunity specification?

LM3722IM5-4.63/NOPB provides built-in immunity to short negative-going VCC transients: glitches ≤100 ns in duration are rejected outright, and longer transients require progressively larger overdrive (e.g., 125 mV below threshold) to trigger reset. Figure 14 in the datasheet quantifies maximum allowable transient duration versus overdrive. A 0.1 µF ceramic bypass capacitor placed near the VCC pin further enhances immunity, making LM3722IM5-4.63/NOPB suitable for electrically noisy industrial environments.