Texas Instruments TPS3128E15DBVR

Overview

TPS3128E15DBVR from Texas Instruments is an ultra-low-voltage processor supervisory IC with 1.43 V nominal reset threshold (V_IT–), 180 ms power-on reset delay, manual reset (MR) input, and watchdog timer (WDI) functionality. It operates from 0.9 V to 3.3 V supply, draws 14 µA typical quiescent current, and delivers active-low open-drain RESET output in a 5-pin SOT-23 package. It is used in battery-powered DSP and microcontroller systems requiring reliable voltage monitoring and software hang detection.

For engineers reviewing the TPS3128E15DBVR datasheet, TPS3128E15DBVR pinout, TPS3128E15DBVR application, or TPS3128E15DBVR equivalent, this page provides verified technical context, exact pin functions, real-world use cases, and validated alternative options - all aligned to TI's SLVS227H production data sheet (March 2025 revision).

Technical Context

The TPS3128E15DBVR integrates voltage supervision, a 1.43 V fixed threshold detector with 20 mV hysteresis, a 1.4 s watchdog timeout (t_tout), and a manual reset input that forces RESET assertion independent of VDD or WDI state. Its open-drain RESET output supports flexible pull-up configurations and interfaces directly with processors requiring active-low reset signaling.

It operates across –40°C to +85°C, maintains valid RESET behavior only when VDD ≥ 0.9 V, and uses internal resistor-divider programming to eliminate external components. The device asserts RESET when VDD falls below V_IT– or when WDI fails to toggle within t_tout, and deasserts after VDD rises above V_IT+ = V_IT– + V_HYS for 180 ms.

Key Specifications

Pinout & Package

TPS3128E15DBVR is housed in a 5-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 mm, optimized for space-constrained PCB layouts and reflow-compatible assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervision and watchdog applications.

Compared with TPS3128E15DBVR, TPS3123E15DBVR offers simpler interface but less system flexibility, while TPS3808G15DBVR trades ultra-low-voltage capability for improved threshold accuracy and reduced feature set - making each suitable for distinct power architecture constraints.

Availability

TPS3128E15DBVR is available at Aetrix Electronics and suitable for portable electronics, wireless infrastructure, and industrial control applications requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for TPS3128E15DBVR 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 TPS312x family was designed specifically for low-voltage DSP and microcontroller systems needing integrated voltage monitoring, watchdog supervision, and manual reset - targeting battery-powered and space-constrained industrial applications.

FAQ

What is the exact reset threshold voltage of TPS3128E15DBVR?

The TPS3128E15DBVR has a guaranteed negative-going input threshold (V_IT–) of 1.38 V (min), 1.43 V (typical), and 1.48 V (max) across –40°C to +85°C, corresponding to a nominal 1.5 V supply rail with –5% tolerance per TI's naming convention ('E' = –5%). This value is factory-trimmed and does not require external calibration.

Does TPS3128E15DBVR support manual reset, and how is it implemented?

Yes, TPS3128E15DBVR includes a dedicated MR (manual reset) input on Pin 3. A logic-low signal on MR forces immediate RESET assertion regardless of VDD level or WDI activity. The pin features an internal 90 kΩ pull-up resistor to VDD, so it remains inactive (high) when left floating or connected to a high-impedance source.

What is the watchdog timeout period for TPS3128E15DBVR, and how is it triggered?

The watchdog timeout (t_tout) for TPS3128E15DBVR is specified from 0.8 s (min) to 2.1 s (max), with 1.4 s typical. It is triggered when the WDI pin (Pin 4) remains static - neither rising nor falling - beyond this interval. Any edge (rising or falling) resets the timer; no pulse width or frequency requirements apply beyond minimum edge rate.

Is TPS3128E15DBVR compatible with 0.9 V supply rails, and what happens below that voltage?

Yes, TPS3128E15DBVR operates down to 0.9 V supply (VDD), enabling supervision of ultra-low-power systems. Below 0.9 V, the RESET output becomes undefined and is not guaranteed to remain asserted; the device ceases functional operation, and internal circuitry may behave unpredictably - thus proper system design must ensure VDD never drops below 0.9 V during active supervision.

What package type and footprint does TPS3128E15DBVR use, and are there thermal considerations?

TPS3128E15DBVR uses the 5-pin SOT-23 (DBV) package (2.90 mm × 1.60 mm). Its junction-to-ambient thermal resistance (R_θJA) is 185°C/W. While self-heating is negligible at 14 µA supply current, designers should still follow TI's layout guidance: place a 0.1 µF ceramic capacitor within 2 mm of the VDD pin and ensure adequate copper pour on the GND pad for thermal and noise performance.