Texas Instruments TPS3125J18DBVRG4

Overview

TPS3125J18DBVRG4 from Texas Instruments is an ultra-low-voltage processor supervisory IC with 1.62 V nominal reset threshold, 180 ms power-on reset delay, active-high push-pull RESET output, manual reset (MR) input, and operation down to 0.9 V supply. It monitors 1.8 V rails in DSP and microprocessor systems requiring reliable power sequencing and fault recovery in battery-powered industrial controllers.

For engineers reviewing the TPS3125J18DBVRG4 datasheet, TPS3125J18DBVRG4 pinout, TPS3125J18DBVRG4 application, or TPS3125J18DBVRG4 equivalent, key selection criteria include its fixed 1.62 V threshold (±60 mV), MR-triggered reset assertion, 14 µA typical supply current at 0.9 V, and SOT-23-5 package compatibility with space-constrained embedded designs.

Technical Context

The TPS3125J18DBVRG4 implements a precision voltage comparator with internal hysteresis (20 mV) to prevent false resets during supply transients, paired with a fixed 180 ms reset delay timer that activates only after VDD exceeds VIT+ = VIT− + VHYS. Its active-high RESET output remains asserted until the delay expires, ensuring full system initialization before release.

This device integrates manual reset functionality via the MR pin-asserting low forces immediate RESET activation independent of VDD level-and supports robust noise immunity with 1 µs/V input transition rate requirement on MR and WDI pins. It lacks watchdog timer circuitry, distinguishing it from TPS3123/3124/3128 variants.

Key Specifications

Pinout & Package

TPS3125J18DBVRG4 is housed in a 5-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 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 supervision applications.

Compared with TPS3125J18DBVRG4, TPS3125L30DBVR shifts threshold to 3.0 V rails and TPS3124J18DBVR removes MR while changing RESET polarity-neither offers drop-in replacement capability without schematic or firmware modification.

Availability

TPS3125J18DBVRG4 is available at Aetrix Electronics and suitable for industrial automation, wireless sensor networks, and building management systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TPS3125J18DBVRG4 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 over 50 years of innovation in industrial and automotive electronics.

The TPS312x family was designed specifically for ultra-low-voltage supervision in DSP, microcontroller, and FPGA-based systems-emphasizing minimal supply current, precise threshold accuracy, and integrated reset timing without external components.

FAQ

What is the exact reset threshold voltage of the TPS3125J18DBVRG4?

The TPS3125J18DBVRG4 has a nominal reset threshold voltage of 1.62 V, with a guaranteed range of 1.56 V to 1.68 V over the full –40°C to +85°C operating temperature range. This value is factory-programmed and does not require external calibration or trimming. The TPS3125J18DBVRG4 uses internal resistor division to achieve this fixed threshold, eliminating the need for external components while maintaining tight tolerance.

Does the TPS3125J18DBVRG4 include a watchdog timer function?

No, the TPS3125J18DBVRG4 does not include a watchdog timer. It belongs to the TPS3125 variant group, which provides manual reset (MR) input and active-high push-pull RESET output but omits the WDI pin and associated watchdog logic. Watchdog functionality is exclusive to TPS3123, TPS3124, and TPS3128 devices. The TPS3125J18DBVRG4 relies solely on voltage monitoring and MR-triggered reset.

What is the function of Pin 4 on the TPS3125J18DBVRG4?

Pin 4 on the TPS3125J18DBVRG4 is a no-connect (NC) terminal. It is internally unconnected and must remain floating or be tied to GND per TI's recommended layout practices. This pin serves no electrical function and should not be used for signal routing, grounding, or decoupling. The TPS3125J18DBVRG4 uses Pins 1 (RESET), 2 (GND), 3 (MR), and 5 (VDD) for all operational functions.

Can the TPS3125J18DBVRG4 operate from a 0.9 V supply?

Yes, the TPS3125J18DBVRG4 is fully specified to operate from a minimum supply voltage of 0.9 V, with typical supply current of 14 µA at that level. Its internal circuitry remains functional and RESET output valid down to 0.9 V, making it suitable for ultra-low-power applications such as energy-harvesting nodes and deeply discharged battery systems. The TPS3125J18DBVRG4 maintains accurate threshold detection and delay timing across the entire 0.9 V to 3.3 V range.

What package type and dimensions does the TPS3125J18DBVRG4 use?

The TPS3125J18DBVRG4 uses a 5-pin SOT-23 (DBV) package with nominal body dimensions of 2.90 mm × 1.60 mm. It is RoHS-compliant, lead-free (NIPDAU/Sn finish), and rated for Level-1 moisture sensitivity (260°C peak reflow). The package supports standard surface-mount assembly and is compatible with automated pick-and-place equipment. The TPS3125J18DBVRG4 shares footprint and soldering profiles with other TPS312x DBV variants.