Texas Instruments TPS3813L30DBVR

Overview

TPS3813L30DBVR from Texas Instruments is a window-watchdog supervisory IC for microcontroller and DSP systems, featuring a fixed 2.64V supply voltage threshold (VIT), 25ms power-on reset delay, 9µA typical supply current, open-drain RESET output, and programmable watchdog window ratio via WDR/WDT pins. It operates across –40°C to +85°C and is used in safety-critical embedded systems requiring dual-voltage monitoring and timing supervision.

For engineers reviewing the TPS3813L30DBVR datasheet, TPS3813L30DBVR pinout, TPS3813L30DBVR application, or TPS3813L30DBVR equivalent, key selection considerations include its precise 2.64V VIT tolerance (±30mV), configurable watchdog window ratios (e.g., 1:31.8 to 1:127.7), SOT-23-6 package footprint, low-power operation, and immunity to VDD transients with 3µs glitch immunity.

Technical Context

The TPS3813L30DBVR integrates a precision voltage comparator with internal bandgap reference and hysteresis (35mV) to monitor VDD against its fixed 2.64V threshold, asserting RESET when VDD drops below VIT or rises above VIT+VHYS only after 25ms delay. Its window-watchdog logic requires periodic WDI triggering within user-defined upper and lower time boundaries set by WDT (GND/VDD/external cap) and WDR (GND/VDD).

This architecture enables detection of both software hangs (no WDI pulse) and timing violations (pulse too early or too late), unlike standard watchdogs. The device supports VDD rails from 2V to 6V, delivers 0.2V VOL at 500µA, and maintains functional integrity under transient conditions with 3µs minimum VDD pulse immunity at VIT ±0.2V.

Key Specifications

Pinout & Package

TPS3813L30DBVR is housed in a 6-pin SOT-23 package (2.90mm × 1.60mm body size) with exposed pad not electrically connected. Pin assignments are validated per TI SLVS331J Rev. August 2024.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3813L30DBVR, TPS3813K33DBVR offers higher VIT for tighter 3.3V rail monitoring but reduced brownout margin on 3.0V systems, while MAX6373KA26T provides simpler supervision without windowed timing validation-making it unsuitable for IEC 61508 or ISO 26262 applications requiring dual-boundary fault detection.

Availability

TPS3813L30DBVR is available at Aetrix Electronics and suitable for active antenna systems, electricity meters, infusion pumps, and HVAC controllers requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for TPS3813L30DBVR 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 company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and communications markets.

The TPS3813xxx family was designed specifically for safety-critical embedded systems needing combined voltage supervision and windowed watchdog functionality-targeting medical devices, smart grid infrastructure, and 5G infrastructure where deterministic fault detection is mandatory.

FAQ

What is the exact VIT threshold voltage for TPS3813L30DBVR and how tightly is it specified?

The TPS3813L30DBVR has a nominal VIT threshold of 2.64V, with a guaranteed range of 2.58V to 2.70V over –40°C to +85°C. This ±30mV tolerance is factory-trimmed and applies across full temperature and supply voltage ranges, enabling reliable brownout detection on 3.0V systems without external calibration. The TPS3813L30DBVR datasheet specifies this value in Section 6.5 Electrical Characteristics under VIT for the L30 variant.

How does the window-watchdog function of TPS3813L30DBVR differ from a standard watchdog timer?

Unlike standard watchdogs that only detect absence of pulses, the TPS3813L30DBVR implements a true window-watchdog: it requires WDI triggers to occur within both an upper time limit (e.g., 2.5s) and a lower time limit (e.g., 19.6ms), defined by WDT and WDR pin configurations. This enables detection of both software hangs and accelerated execution-critical for safety standards like IEC 61508. The TPS3813L30DBVR achieves this using an internal oscillator and ratio-based boundary logic.

Can TPS3813L30DBVR's RESET output interface directly with a 5V microcontroller reset pin?

Yes, the TPS3813L30DBVR's open-drain RESET output can be pulled up to 5V (or any voltage ≤6V) independently of its VDD supply, which may be 2.5V–6V. A 10kΩ–100kΩ pull-up resistor to the MCU's 5V rail ensures valid logic-high levels. The TPS3813L30DBVR guarantees VOL ≤0.4V at 2mA sink current, meeting standard TTL/CMOS reset input thresholds. No level-shifter is needed.

What is the minimum recommended bypass capacitance for TPS3813L30DBVR's VDD pin?

Texas Instruments specifies a minimum 0.1µF ceramic capacitor placed as close as possible to the VDD and GND pins of the TPS3813L30DBVR. This is required to stabilize the internal bandgap reference and ensure accurate VIT detection during power-up and transient events. Larger values (up to 1µF) may be used in noisy environments, but the 0.1µF value is sufficient for most applications and is explicitly shown in the Typical Operating Circuit of the TPS3813L30DBVR datasheet.

Does TPS3813L30DBVR require external components to configure its watchdog window settings?

No external components are required to configure the TPS3813L30DBVR watchdog window-basic operation uses only WDT and WDR pin connections to GND or VDD to select among four fixed window ratios (e.g., 1:31.8 or 1:127.7). An external capacitor (155pF–63nF) on WDT enables fine-tuned upper-bound adjustment, but is optional. All timing parameters-including 25ms reset delay-are internally generated; no RC networks are needed for core functionality.