Texas Instruments TPS3125J18DBVT

Overview

TPS3125J18DBVT from Texas Instruments is an ultra-low-voltage supervisor IC designed for power-rail monitoring and reset generation in DSP and processor-based systems. It provides 1.62 V nominal reset threshold (V_IT–), 180 ms fixed reset delay, manual reset input (MR), and push-pull active-high RESET output - all in a 5-pin SOT-23 package operating from 0.9 V to 3.3 V supply.

For engineers reviewing the TPS3125J18DBVT datasheet, TPS3125J18DBVT pinout, TPS3125J18DBVT application, or TPS3125J18DBVT equivalent, this page delivers verified functional identity, validated pin roles, confirmed timing behavior, exact threshold tolerance (±0.06 V), and real-world deployment context for battery-powered and industrial embedded systems.

Technical Context

The TPS3125J18DBVT implements a fixed-threshold voltage monitor with built-in hysteresis (20 mV) and a dedicated manual reset input that forces active-high RESET assertion independent of VDD level. Its internal reference and comparator circuitry ensure valid RESET output only when VDD ≥ 0.9 V, and the output remains asserted for the full 180 ms delay after VDD rises above V_IT+ = V_IT– + V_HYS.

This device belongs to the TPS312x family variant with active-high push-pull RESET, no watchdog timer, and 1.8 V nominal supply compatibility. It shares the same SOT-23-5 footprint and –40°C to +85°C temperature range as other family members but excludes WDI functionality and uses J18 threshold coding (1.62 V typical).

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90 mm × 1.60 mm body size, 5-pin surface-mount, lead-free (RoHS-compliant), moisture sensitivity level 1 (260°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3125L30DBVR and TPS3808G18DBVR, the TPS3125J18DBVT delivers optimal integration for fixed 1.8 V rail supervision - eliminating external components, minimizing board area, and reducing total solution cost while maintaining industrial-grade temperature performance and MR-driven recovery capability.

Availability

TPS3125J18DBVT is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, wireless edge gateways, and building automation controllers requiring stable component supply across extended product lifecycles.

Supply support for TPS3125J18DBVT 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 real-time control ICs.

The TPS312x family was engineered specifically for low-voltage processor supervision in battery-powered and industrial systems, emphasizing minimal quiescent current, fixed-threshold accuracy, and robust reset timing under varying thermal and supply conditions.

FAQ

What is the exact reset threshold voltage of the TPS3125J18DBVT?

The TPS3125J18DBVT has a guaranteed negative-going input threshold voltage (V_IT–) between 1.56 V and 1.68 V at –40°C to +85°C, with 1.62 V typical. This matches the "J18" nomenclature indicating a 10% below nominal 1.8 V rail, and is factory-trimmed - no external calibration is needed. The TPS3125J18DBVT uses internal resistor dividers to achieve this precision without external components.

Does the TPS3125J18DBVT include a watchdog timer function?

No, the TPS3125J18DBVT does not include a watchdog timer. Per TI's device naming convention and functional block diagram, only TPS3123/3124/3128 variants incorporate WDI input and timeout logic. The TPS3125J18DBVT is designated for pure voltage supervision with manual reset (MR) and fixed-delay active-high RESET - making it ideal for systems where software hang detection is handled externally.

What is the function of Pin 5 on the TPS3125J18DBVT?

Pin 5 on the TPS3125J18DBVT is a no-connect (NC) terminal. It is internally unconnected and must remain floating or be tied to GND per TI's layout recommendations. Unlike TPS3123/3128 variants that assign Pin 5 to WDI, the TPS3125J18DBVT uses Pins 1–4 exclusively for RESET, GND, MR, and VDD - leaving Pin 5 unused to maintain package compatibility across the family.

Can the TPS3125J18DBVT operate from a 0.9 V supply?

Yes, the TPS3125J18DBVT is fully specified to operate down to 0.9 V supply voltage (VDD), with functional RESET output and valid MR response. Its internal bandgap reference and comparator remain stable at this level, enabling supervision of ultra-low-power subsystems such as energy-harvesting nodes or deep-sleep microcontrollers. The TPS3125J18DBVT's 14 µA typical supply current at 0.9 V further supports long-duration battery operation.

Is the TPS3125J18DBVT pin-compatible with other TPS312x devices in SOT-23-5?

Yes, the TPS3125J18DBVT shares identical SOT-23-5 (DBV) pinout and mechanical footprint with all TPS312x family members, including TPS3123J18DBVT and TPS3124J18DBVT. Pin assignments for RESET, GND, MR, VDD, and NC are consistent across variants - enabling drop-in replacement in existing layouts when switching between active-low, active-high, or watchdog-enabled versions, provided functional requirements align.