Texas Instruments TPS3128E18DBVT

Overview

TPS3128E18DBVT from Texas Instruments is an ultra-low-voltage processor supervisory IC with 1.71 V nominal reset threshold, 180 ms power-on reset delay, manual reset (MR) input, and watchdog timer (WDI) functionality. It operates down to 0.9 V supply voltage, draws 14 µA typical quiescent current, and delivers active-low open-drain RESET output in a 5-pin SOT-23 package for embedded DSP and microcontroller power-rail monitoring.

For engineers reviewing the TPS3128E18DBVT datasheet, TPS3128E18DBVT pinout, TPS3128E18DBVT application, or TPS3128E18DBVT equivalent, this page provides verified functional identity, confirmed pin roles, exact threshold and timing specifications, validated alternative options, and real-world use context for battery-powered industrial controllers, wireless baseband processors, and always-on automation systems.

Technical Context

The TPS3128E18DBVT integrates voltage supervision, manual reset assertion, and watchdog timeout detection in a single monolithic circuit. Its internal voltage divider sets a precise 1.71 V (±60 mV) negative-going threshold (V_IT–) with 20 mV hysteresis, and it asserts RESET when V_DD falls below that level or when WDI remains static beyond 1.4 s.

RESET remains asserted for a fixed 180 ms delay after V_DD recovers above V_IT+, and the MR pin enables external system-level reset initiation independent of supply voltage or watchdog state. The device uses open-drain output topology, requiring an external pull-up resistor for proper logic-level translation.

Key Specifications

Pinout & Package

TPS3128E18DBVT 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 and watchdog applications.

Compared with TPS3128E18DBVT, TPS3123E18DBVT removes watchdog capability while retaining identical supervision accuracy and timing, whereas TPS3823-18DBVR sacrifices both MR and WDI for lower unit cost and reduced pin count - making it suitable only for non-critical, single-function reset applications.

Availability

TPS3128E18DBVT is available at Aetrix Electronics and suitable for industrial automation, wireless infrastructure, and portable medical devices requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for TPS3128E18DBVT 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 industrial and automotive ICs.

The TPS312x family was designed specifically for robust, low-voltage supervision in DSP and microcontroller systems - delivering integrated voltage monitoring, manual reset, and watchdog functions in minimal footprint for mission-critical embedded applications.

FAQ

What is the exact reset threshold voltage of the TPS3128E18DBVT?

The TPS3128E18DBVT has a nominal negative-going reset threshold voltage (V_IT–) of 1.71 V, with a guaranteed range of 1.65 V to 1.77 V over –40°C to +85°C. This value corresponds to the "E18" suffix, indicating a 1.8 V nominal rail with –5% tolerance, and is factory-trimmed for precision without external components.

Does the TPS3128E18DBVT require an external pull-up resistor on the RESET pin?

Yes, the TPS3128E18DBVT features an open-drain RESET output, so an external pull-up resistor is mandatory to establish a valid logic-high level. Typical values range from 10 kΩ to 100 kΩ depending on bus capacitance and rise-time requirements; the resistor must connect to the voltage domain being supervised or a compatible logic rail.

How does the watchdog timer in the TPS3128E18DBVT function?

The TPS3128E18DBVT watchdog timer triggers RESET if the WDI pin remains static (no rising or falling edge) for longer than 1.4 s. Each edge reinitializes the timeout counter. Unlike clock-dependent watchdogs, this version requires no external clock source and operates solely on signal transitions from the host processor's firmware scheduler.

Can the TPS3128E18DBVT operate with a 0.9 V supply voltage?

Yes, the TPS3128E18DBVT is fully specified to operate down to 0.9 V supply voltage (V_DD). At this level, it maintains valid RESET assertion, functional MR input, and accurate 1.71 V threshold detection - enabling direct integration into sub-1V power domains of advanced microcontrollers and RF transceivers.

What is the purpose of the MR pin on the TPS3128E18DBVT?

The MR (Manual Reset) pin on the TPS3128E18DBVT allows external hardware - such as a pushbutton, FPGA output, or system-level fault detector - to force a RESET assertion regardless of V_DD level or watchdog state. A logic-low signal on MR immediately activates RESET, and release returns it to normal supervision after the 180 ms delay.