Texas Instruments TPS3123J12DBVT

Overview

TPS3123J12DBVT from Texas Instruments is an ultra-low-voltage processor supervisory IC with 1.08 V nominal reset threshold, 180 ms fixed 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 push-pull RESET output in a 5-pin SOT-23 package for DSP and microprocessor power-rail monitoring.

For engineers reviewing the TPS3123J12DBVT datasheet, TPS3123J12DBVT pinout, TPS3123J12DBVT application, or TPS3123J12DBVT equivalent, this page provides verified circuit role, validated timing parameters, confirmed pin functions, and real-world use cases in battery-powered systems, industrial automation, and wireless infrastructure where reliable low-voltage reset supervision is critical.

Technical Context

The TPS3123J12DBVT integrates voltage monitoring, power-on reset generation, manual reset assertion, and watchdog timeout detection in a single 5-pin SOT-23 device. Its internal voltage divider sets a precise 1.08 V (±40 mV) threshold with 15 mV hysteresis, and the watchdog timer triggers RESET if WDI transitions are missed beyond 0.8–2.1 s.

RESET assertion occurs when VDD falls below VIT− or MR is pulled low; deassertion follows a fixed 100–260 ms delay after VDD rises above VIT+ = VIT− + VHYS. The device supports operation from −40°C to +85°C and requires no external components for threshold setting or timing.

Key Specifications

Pinout & Package

TPS3123J12DBVT is housed in a 5-pin SOT-23 (DBV) package with 2.90 mm × 1.60 mm body size, optimized for space-constrained PCBs. Pin 1 is RESET (active-low output), Pin 2 is GND, Pin 3 is MR (manual reset input), Pin 4 is WDI (watchdog timer input), and Pin 5 is VDD (supply input).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3123J12DBVT, TPS3123J12DBVR offers identical supervision performance with modern packaging and lifecycle support, while MAX6326L31D2T provides simpler reset-only functionality at higher thresholds and without programmable supervision features.

Availability

TPS3123J12DBVT is available at Aetrix Electronics and suitable for portable electronics, industrial controllers, and wireless infrastructure requiring stable component supply despite its obsolete status - we maintain legacy stock with full traceability and documentation support.

Supply support for TPS3123J12DBVT 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 90 years of innovation in industrial, automotive, and communications markets.

The TPS312x family was designed specifically for ultra-low-voltage DSP and microprocessor supervision, integrating reset generation, watchdog monitoring, and manual reset in minimal footprint to address reliability challenges in battery-powered and always-on systems.

FAQ

What is the exact reset threshold voltage of the TPS3123J12DBVT?

The TPS3123J12DBVT has a nominal reset threshold voltage of 1.08 V, with a guaranteed range of 1.04 V to 1.12 V over the full −40°C to +85°C operating temperature range. This value is factory-trimmed and applies specifically to the J12 variant, which targets 1.2 V supply rails with a −10% offset. The TPS3123J12DBVT does not require external resistors to set this threshold.

Does the TPS3123J12DBVT support watchdog timer functionality?

Yes, the TPS3123J12DBVT includes a fully integrated watchdog timer with a timeout range of 0.8 s to 2.1 s. It monitors digital pulses on the WDI pin and asserts the active-low RESET output if no rising or falling edge is detected within that interval. The timer resets on each valid WDI transition, making it suitable for detecting software hangs in DSP or microcontroller applications.

What is the function of the MR pin on the TPS3123J12DBVT?

The MR (Manual Reset) pin on the TPS3123J12DBVT is an active-low input that forces the RESET output low regardless of VDD level or watchdog state. When pulled to logic low, it immediately asserts RESET; release to high (or floating, due to internal 90 kΩ pullup) allows RESET to deassert after the 180 ms delay. This enables hardware-initiated resets for testing, safety interlocks, or field service.

Is the TPS3123J12DBVT pin-compatible with other TPS312x variants?

Yes, the TPS3123J12DBVT shares identical 5-pin SOT-23 (DBV) pinout and package dimensions with all TPS312x family members, including TPS3123J12DBVR, TPS3124J12DBVT, and TPS3125G15DBVR. Pin 1 is RESET, Pin 2 is GND, Pin 3 is MR, Pin 4 is WDI, and Pin 5 is VDD - no PCB redesign is needed when substituting within the same package variant.

What is the supply current consumption of the TPS3123J12DBVT at minimum operating voltage?

The TPS3123J12DBVT draws 14 µA typical supply current at VDD = 0.9 V and TA = +25°C, with no significant increase across the full −40°C to +85°C range. This ultra-low quiescent current enables deployment in energy-sensitive applications such as coin-cell-powered sensors and always-on edge nodes where standby power budget is constrained to single-digit µA.