Texas Instruments LP3470A438DBVR

Overview

LP3470A438DBVR from Texas Instruments is an ultra-low-power voltage supervisor IC designed for precise power-on reset and brownout detection in microcontroller systems. It features a factory-programmed 4.38 V reset threshold (VIT−), ±1% accuracy over −40°C to 125°C, 0.3 µA typical quiescent current, open-drain RESET output, and programmable reset delay via external capacitor on SRT pin. It operates down to VCC = 0.95 V and is used in battery-powered industrial controllers and embedded safety monitors.

For engineers reviewing the LP3470A438DBVR datasheet, LP3470A438DBVR pinout, LP3470A438DBVR application, or LP3470A438DBVR equivalent, key selection criteria include reset threshold tolerance, supply voltage range (0.95–10 V), SRT-capacitor programmability (50 µs to 6.2 s), hysteresis (200 mV typ.), and SOT-23-5 package compatibility with space-constrained PCB layouts.

Technical Context

The LP3470A438DBVR implements a precision bandgap-based voltage reference comparator with internal hysteresis (200 mV typical) to prevent chatter during slow-rising or noisy VCC transitions. Its reset assertion logic triggers when VCC falls below 4.38 V (VIT−), and RESET remains active for a user-defined time after VCC recovers above VIT− + VHYS.

Reset timing is controlled by an internal RC network tied to the SRT pin, where tD = 619 × CSRT (in µF) yields delay in ms - enabling design flexibility from 50 µs (SRT floating) to 619 ms (1 µF) without changing ICs. The open-drain RESET output supports level-shifting up to 10 V and requires an external pull-up resistor.

Key Specifications

Pinout & Package

LP3470A438DBVR is housed in a 5-pin SOT-23 (DBV) package measuring 1.60 mm × 2.90 mm, optimized for high-density PCB layouts and reflow-compatible assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with TPS3808G33DBVR and MAX6326UT44D3+, the LP3470A438DBVR delivers tighter threshold accuracy (±1% vs ±2.5%), lower quiescent current (0.3 µA vs 1.1–1.6 µA), and field-programmable delay - making it optimal for precision, low-power, and timing-flexible industrial and medical applications.

Availability

LP3470A438DBVR is available at Aetrix Electronics and suitable for industrial motor control, smart building security sensors, factory automation field transmitters, portable medical diagnostic devices, and battery-powered instrumentation requiring stable component supply and long-term lifecycle support.

Supply support for LP3470A438DBVR 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 specializing in analog and embedded processing technologies, with leadership in power management, signal chain, and high-reliability ICs for industrial, automotive, and consumer markets.

The LP3470A438DBVR belongs to TI's ultra-low-power voltage supervisor product line, engineered specifically for deterministic power-on reset and brownout protection in energy-constrained, thermally demanding embedded systems.

FAQ

What is the exact reset threshold voltage of the LP3470A438DBVR?

The LP3470A438DBVR has a factory-programmed negative-going input threshold (VIT−) of 4.38 V, with ±1% typical accuracy over −40°C to 125°C. Its positive-going threshold (VIT+) is 4.58 V due to 200 mV hysteresis. This value is laser-trimmed during production and documented in TI's LP3470A device comparison table.

How do I calculate the reset delay time for LP3470A438DBVR using an external capacitor?

For LP3470A438DBVR, reset delay tD (ms) = 619 × CSRT (µF). For example, a 100 nF (0.1 µF) capacitor yields ~61.9 ms delay. The relationship holds for capacitors up to 10 µF; beyond that, discharge time may compromise accuracy. SRT pin must be connected to GND through the capacitor - leaving it floating gives minimum 50 µs delay.

Can LP3470A438DBVR operate with a 3.3 V supply rail?

No - LP3470A438DBVR is designed to monitor rails near its 4.38 V threshold. While it functions down to VCC = 0.95 V, asserting RESET requires VCC to fall below 4.38 V. Using it on a 3.3 V rail would cause permanent RESET assertion. For 3.3 V supervision, select LP3470A308DBVR (3.08 V threshold) instead.

What is the maximum allowable voltage on the RESET pin of LP3470A438DBVR?

The RESET pin of LP3470A438DBVR supports up to 10 V, independent of VCC. This allows pulling up to higher voltage rails (e.g., 5 V or 10 V) while monitoring a lower VCC - useful for interfacing with MCUs having different I/O voltage levels. Absolute maximum rating is 12 V, but recommended operating limit is 10 V per TI's Electrical Characteristics table.

Does LP3470A438DBVR require a bypass capacitor on the VCC pin?

Yes - TI recommends a minimum 0.1 µF ceramic capacitor placed as close as possible to the VCC pin and GND. This stabilizes the internal reference, improves noise immunity, and prevents false resets caused by high-frequency transients or LDO output ripple. Layout guidelines specify short traces and direct connection to minimize inductance.