Texas Instruments TPS3813J25DBVR

Overview

TPS3813J25DBVR from Texas Instruments is a window-watchdog supervisory IC for microcontroller and DSP systems, featuring a fixed 2.25V supply voltage threshold (VIT), 25ms power-on reset delay, 9µA typical supply current, open-drain RESET output, and operation from –40°C to +85°C. It ensures reliable system initialization and runtime fault detection in safety-critical embedded applications.

For engineers reviewing the TPS3813J25DBVR datasheet, TPS3813J25DBVR pinout, TPS3813J25DBVR application, or TPS3813J25DBVR equivalent, key selection considerations include its programmable watchdog window ratio (via WDR/WDT pins), glitch-immune VDD monitoring, fixed 2.25V threshold accuracy, SOT-23-6 package compatibility, and absence of external timing components.

Technical Context

The TPS3813J25DBVR integrates a precision voltage supervisor and a user-programmable window-watchdog timer. Its internal comparator monitors VDD against a factory-trimmed 2.25V threshold with 30mV hysteresis, while the watchdog requires WDI pulses within a configurable time window defined by WDT (upper bound) and WDR (lower bound) pin states or an external capacitor.

During power-up, RESET asserts when VDD exceeds 1.1V and remains active until VDD rises above 2.25V, then holds low for 25ms typical before releasing. The device operates from 2V to 6V supply, supports open-drain RESET pull-up to up to 6V, and delivers glitch immunity with 3µs minimum pulse width rejection at VDD.

Key Specifications

Pinout & Package

TPS3813J25DBVR is housed in a 6-pin SOT-23 package (2.90mm × 1.60mm body size) with standard lead pitch and thermal performance suitable for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3813L30DBVR and TPS3803-01DBVR, the TPS3813J25DBVR uniquely combines 2.25V precision thresholding with full window-watchdog capability in the same footprint-enabling both power-rail supervision and deterministic firmware health verification in safety-critical 2.5V systems.

Availability

TPS3813J25DBVR is available at Aetrix Electronics and suitable for infusion pumps, HVAC controllers, electricity meters, and active antenna systems requiring stable component supply, long-lifecycle support, and traceable sourcing for medical and industrial certifications.

Supply support for TPS3813J25DBVR 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 with emphasis on reliability, precision, and industrial-grade qualification.

The TPS3813xxx product line was designed specifically for safety-critical processor supervision-integrating precision voltage monitoring and programmable window-watchdog functionality into a single 6-pin SOT-23 IC for medical, energy, and communications equipment.

FAQ

What is the exact supply voltage threshold (VIT) of the TPS3813J25DBVR?

TPS3813J25DBVR has a factory-trimmed negative-going input threshold voltage (VIT) of 2.25V, with a guaranteed range of 2.20V to 2.30V over –40°C to +85°C. This value is fixed and does not require external configuration, making it ideal for supervising 2.5V rails where precise undervoltage detection is required.

How does the window-watchdog function in the TPS3813J25DBVR differ from a standard watchdog timer?

The TPS3813J25DBVR implements a true window-watchdog that requires WDI pulses to occur within a defined time interval-not just before timeout. By configuring WDR and WDT pins, users set both upper (e.g., 2.5s) and lower (e.g., 19.6ms) boundaries, enabling detection of both software hangs and premature/faster-than-expected execution-critical for functional safety compliance.

Can the TPS3813J25DBVR operate from a 5V supply rail?

Yes, TPS3813J25DBVR supports VDD from 2V to 6V per its Recommended Operating Conditions. When powered from 5V, it continues to monitor the 2.25V threshold on the same VDD pin and maintains 9µA typical supply current. The open-drain RESET output can be pulled up to any voltage ≤6V, independent of VDD.

What is the purpose of the WDR pin on the TPS3813J25DBVR?

The WDR (Watchdog Ratio) pin on TPS3813J25DBVR selects the lower boundary of the watchdog window relative to the upper timeout set by WDT. Tying WDR to GND yields ratios like 1:31.8; tying to VDD yields wider ratios like 1:127.7. This pin must be hard-connected-floating WDR causes undefined watchdog behavior and potential spurious resets.

Does the TPS3813J25DBVR require external components for basic operation?

No, TPS3813J25DBVR requires no external timing components for core supervision. A 0.1µF ceramic bypass capacitor on VDD is mandatory for stable operation, but the 25ms reset delay, 2.25V threshold, and watchdog timing are all internally generated. External capacitors on WDT are optional and used only for fine-tuning the upper watchdog timeout beyond the two fixed settings.