Texas Instruments TPS3128E15DBVT

Overview

TPS3128E15DBVT 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 input (MR), and watchdog timer (WDI) functionality. It operates down to 0.9 V supply voltage, draws 14 µA typical supply current, and delivers active-low open-drain RESET output in a 5-pin SOT-23 package for embedded DSP and microcontroller systems requiring reliable power-up sequencing and software hang detection.

For engineers reviewing the TPS3128E15DBVT datasheet, TPS3128E15DBVT pinout, TPS3128E15DBVT application, or TPS3128E15DBVT equivalent, this page provides verified functional identity, confirmed pin roles, exact threshold and timing specifications, validated alternative parts, and real-world use context for low-voltage industrial and portable electronics design.

Technical Context

The TPS3128E15DBVT integrates voltage supervision, watchdog timer, and manual reset in a single 5-pin SOT-23 device. Its fixed 1.43 V threshold (±5% over –40°C to +85°C) triggers RESET when V_DD falls below V_IT–, with 20 mV hysteresis and 180 ms delay after V_DD rises above V_IT+. The WDI input detects missing edges within 0.8–2.1 s timeout window, and MR forces immediate RESET assertion independent of supply or watchdog state.

This variant belongs to the TPS312x family's E-series (–5% nominal threshold), uses open-drain RESET output, and supports operation across full industrial temperature range (–40°C to +85°C) with 14 µA typical quiescent current at 0.9 V - enabling battery-sensitive applications where supply rail monitoring and software fault recovery must coexist without external components.

Key Specifications

Pinout & Package

TPS3128E15DBVT is housed in a 5-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 mm, optimized for high-density PCB layouts and automated assembly. Pin functions are validated per TI SLVS227H datasheet Figure 5-1 and Table 5-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3128E15DBVT, TPS3123E15DBVT removes watchdog functionality while retaining identical threshold and pinout - simplifying design where software supervision is handled externally; TPS3823-15DBVR offers tighter threshold accuracy and stronger output drive but sacrifices MR and watchdog, making it ideal for fixed-supply applications without manual intervention requirements.

Availability

TPS3128E15DBVT is available at Aetrix Electronics and suitable for industrial automation, portable medical devices, and wireless infrastructure requiring stable component supply with long-term lifecycle assurance.

Supply support for TPS3128E15DBVT 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 delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The TPS312x product line was designed specifically for ultra-low-voltage processor supervision in space-constrained, battery-sensitive systems - integrating reset generation, watchdog timing, and manual reset in minimal footprint SOT-23 packages.

FAQ

What is the exact reset threshold voltage of the TPS3128E15DBVT?

The TPS3128E15DBVT has a nominal reset threshold voltage (V_IT–) of 1.43 V, with a guaranteed range of 1.38 V to 1.48 V across –40°C to +85°C. This value corresponds to the "E" suffix (–5% of 1.5 V nominal) and is factory-trimmed - no external components are needed to set the threshold.

Does the TPS3128E15DBVT require an external pull-up resistor on the RESET pin?

Yes, the TPS3128E15DBVT features an open-drain RESET output, so an external pull-up resistor is mandatory to establish a valid high-level logic state. The value depends on bus capacitance and rise-time requirements, but 10 kΩ to 100 kΩ to a compatible voltage rail (e.g., 1.8 V or 3.3 V) is typical for most applications using the TPS3128E15DBVT.

How does the watchdog timer in the TPS3128E15DBVT function?

The TPS3128E15DBVT watchdog timer triggers RESET if no edge (rising or falling) occurs on the WDI pin within 0.8–2.1 s. Each valid edge resets the timeout counter. If WDI is left floating or held static, timeout occurs. This behavior ensures detection of software hangs in the host processor - a core function of the TPS3128E15DBVT.

Can the TPS3128E15DBVT operate from a 0.9 V supply?

Yes, the TPS3128E15DBVT is fully specified to operate from 0.9 V to 3.3 V. At 0.9 V, it delivers 14 µA typical supply current and maintains valid RESET assertion/deassertion behavior - making it uniquely suited for next-generation ultra-low-voltage systems where other supervisors fail to function.

What is the purpose of the MR pin on the TPS3128E15DBVT?

The MR (Manual Reset) pin on the TPS3128E15DBVT allows external hardware - such as a front-panel button, system supervisor, or fault detector - to force an immediate RESET assertion regardless of V_DD level or WDI state. A logic-low pulse on MR causes RESET to go active within 0.1 µs, providing deterministic recovery outside software control - a key safety feature in the TPS3128E15DBVT.