Texas Instruments TPS3126E15DBVT

Overview

TPS3126E15DBVT from Texas Instruments is an ultra-low-voltage processor supervisory IC with active-high reset output, 1.43 V nominal reset threshold (V_IT–), 180 ms fixed reset delay, manual reset input (MR), and open-drain RESET output - designed for reliable power-on initialization and fault recovery in low-power DSP and microcontroller systems operating down to 0.9 V.

For engineers reviewing the TPS3126E15DBVT datasheet, TPS3126E15DBVT pinout, TPS3126E15DBVT application, or TPS3126E15DBVT equivalent, this device delivers precise voltage supervision with integrated manual reset and open-drain topology for flexible system-level reset signaling in battery-powered and industrial embedded designs.

Technical Context

The TPS3126E15DBVT implements a fixed-threshold voltage monitor with internal hysteresis (20 mV) and a 180 ms power-on reset timer that activates only when V_DD ≥ 0.9 V. Its MR input accepts logic-low signals to force reset independently of supply voltage level or watchdog state.

This variant belongs to the TPS312x family's E-series (–5% threshold offset), features open-drain RESET output, lacks watchdog timer functionality, and operates across –40°C to +85°C with 14 µA typical supply current at 0.9 V.

Key Specifications

Pinout & Package

TPS3126E15DBVT is housed in a 5-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 mm, optimized for space-constrained PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3126E15DBVT, TPS3125E15DBVT offers simplified drive but loses wired-OR capability, while TPS3808G15DBVR trades fixed accuracy for configurability - making the TPS3126E15DBVT optimal for cost-sensitive, space-constrained designs requiring robust multi-rail reset coordination.

Availability

TPS3126E15DBVT is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, smart building HVAC controllers, and wireless edge gateways requiring stable component supply and long-term industrial lifecycle support.

Supply support for TPS3126E15DBVT 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, embedded processing, and connectivity solutions for industrial, automotive, and consumer markets.

The TPS312x product line delivers ultra-low-voltage supervisory circuits for DSP and microcontroller-based systems, emphasizing minimal external components, wide supply range, and robust reset timing for mission-critical embedded applications.

FAQ

What is the exact reset threshold voltage of the TPS3126E15DBVT?

The TPS3126E15DBVT has a guaranteed negative-going input threshold voltage (V_IT–) between 1.38 V and 1.48 V, with a nominal value of 1.43 V. This –5% offset from the 1.5 V nominal supply is factory-trimmed and includes 20 mV hysteresis to prevent chatter near the trip point. The TPS3126E15DBVT maintains this specification across –40°C to +85°C.

Does the TPS3126E15DBVT include a watchdog timer function?

No, the TPS3126E15DBVT does not include a watchdog timer. It belongs to the TPS3125/3126 subgroup, which provides manual reset (MR) and active-high open-drain RESET but omits the WDI input and associated timeout logic. Watchdog functionality is present only in TPS3123/3124/3128 variants. The TPS3126E15DBVT focuses on precise voltage supervision and hardware-initiated reset control.

What is the purpose of Pin 5 (NC) on the TPS3126E15DBVT?

Pin 5 on the TPS3126E15DBVT is designated NC (No Connect) and is internally unconnected. It must not be used as a signal or power path. Per TI's recommended practice, this pin may be left floating or tied to GND to improve mechanical stability and reduce noise coupling - but it serves no electrical function in the TPS3126E15DBVT circuit operation.

How does the open-drain RESET output of the TPS3126E15DBVT interface with a 3.3 V microcontroller?

The TPS3126E15DBVT's open-drain RESET output requires an external pull-up resistor to the target logic rail - e.g., 3.3 V - to establish the high state. When asserted, the pin pulls low; when deasserted, the pull-up defines the logic-high voltage. This allows direct interfacing with 3.3 V MCUs without level shifters, and supports wired-OR reset buses shared across multiple supervisors. The TPS3126E15DBVT datasheet specifies maximum sink current of 5 mA for reliable drive strength.

Is the TPS3126E15DBVT compatible with 0.9 V supply operation?

Yes, the TPS3126E15DBVT is fully specified to operate with supply voltages as low as 0.9 V. Its internal circuitry remains functional and RESET output is valid down to this minimum V_DD. At 0.9 V, supply current is 14 µA typical, and the 180 ms reset delay remains accurate. The TPS3126E15DBVT is explicitly characterized for this ultra-low-voltage range, making it suitable for energy-harvesting and single-cell battery systems.