Texas Instruments TPS3813J25DBVRG4

Overview

TPS3813J25DBVRG4 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 control.

For engineers reviewing the TPS3813J25DBVRG4 datasheet, TPS3813J25DBVRG4 pinout, TPS3813J25DBVRG4 application, or TPS3813J25DBVRG4 equivalent, key selection considerations include its programmable watchdog window ratio (via WDR/WDT pins), glitch-immune VDD monitoring, fixed 2.25V threshold accuracy (±0.05V), and SOT-23-6 package compatibility with space-constrained PCB layouts.

Technical Context

The TPS3813J25DBVRG4 integrates a precision voltage supervisor and a user-programmable window-watchdog timer in a single 6-pin SOT-23 device. Its internal bandgap reference sets a fixed 2.25V threshold with 30mV hysteresis, and the reset assertion is delayed by 25ms (typical) after VDD exceeds VIT.

Watchdog timing is configured via WDT (upper boundary) and WDR (lower boundary) pins: WDT accepts GND/VDD hard-wire or external capacitor (155pF–63nF); WDR selects GND or VDD to set window ratios from 1:31.8 to 1:127.7. The WDI input requires periodic edge-triggering within this window to prevent RESET assertion.

Key Specifications

Pinout & Package

TPS3813J25DBVRG4 is housed in a 6-pin SOT-23 (DBV) package measuring 2.90mm × 1.60mm, optimized for high-density PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3813J25DBVRG4, TPS3813L30DBVR offers higher threshold voltage for 3V systems but cannot replace it on 2.5V rails, while TPS3808G125DBVR reduces current consumption by 65% but eliminates critical window-watchdog functionality required for SIL-2/IEC 61508 designs.

Availability

TPS3813J25DBVRG4 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 traceable sourcing for medical and industrial certifications.

Supply support for TPS3813J25DBVRG4 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 TPS3813xxx family was designed specifically for functional safety-critical applications requiring both precise voltage monitoring and programmable window-watchdog supervision-targeting IEC 61508, ISO 26262, and UL 60730 compliance in medical, energy, and infrastructure systems.

FAQ

What is the exact supply voltage threshold (VIT) of the TPS3813J25DBVRG4?

The TPS3813J25DBVRG4 has a fixed negative-going input threshold voltage (VIT) of 2.25V, with a guaranteed range of 2.20V to 2.30V over the full –40°C to +85°C operating temperature range. This value is factory-trimmed and does not require external components or calibration. The 2.25V threshold makes the TPS3813J25DBVRG4 ideal for supervising 2.5V supply rails with appropriate headroom for ripple and droop.

How is the 25ms reset delay (t_d) of the TPS3813J25DBVRG4 implemented and is it adjustable?

The 25ms reset delay of the TPS3813J25DBVRG4 is an internal, factory-programmed timer that begins counting once VDD rises above the 2.25V threshold (VIT). It is not adjustable via external components or pins-this fixed delay ensures predictable, repeatable system initialization timing across all units. The typical value is 25ms, with min/max specifications of 20ms and 30ms respectively, verified across temperature and voltage conditions.

Can the TPS3813J25DBVRG4 watchdog window be configured without external capacitors?

Yes, the TPS3813J25DBVRG4 watchdog window can be fully configured using only pin strapping: WDT tied to GND or VDD selects fixed upper time-outs of 0.25s or 2.5s, while WDR tied to GND or VDD selects corresponding lower boundary ratios (e.g., 1:31.8 or 1:124.9). No external capacitor is required-capacitor-based programming is optional for intermediate timing values between those two fixed points.

What is the maximum allowable voltage on the RESET pin of the TPS3813J25DBVRG4?

The RESET pin of the TPS3813J25DBVRG4 supports a maximum voltage of 6V, independent of the VDD supply voltage. This allows the open-drain output to be pulled up to higher-voltage logic rails (e.g., 5V or 3.3V) even when VDD is 2.5V, enabling flexible interfacing with diverse microcontroller reset inputs. The absolute maximum rating for RESET is VDD + 0.3V, but the datasheet explicitly permits up to 6V when the pin is in high-impedance state.

Does the TPS3813J25DBVRG4 require an external bypass capacitor on VDD, and if so, what value?

Yes, the TPS3813J25DBVRG4 requires a ceramic bypass capacitor of 0.1µF placed as close as possible to the VDD and GND pins. This capacitor stabilizes the internal bandgap reference and prevents false resets caused by supply noise or transient droop. The datasheet specifies this as mandatory for best threshold stability and glitch immunity-omitting it degrades VIT accuracy and increases susceptibility to spurious reset events.