Texas Instruments TPS3851H30EDRBR

Overview

TPS3851H30EDRBR from Texas Instruments is a precision voltage supervisor IC with integrated watchdog timer, designed for microcontroller and SoC power-rail monitoring in industrial and embedded systems. It delivers 0.8% undervoltage threshold accuracy (–40°C to +125°C), 200 ms reset timeout (±15%), 10 µA quiescent current, and supports 1.6 V to 6.5 V supply operation - enabling reliable system startup and fault recovery in WLAN access points and IP network cameras.

For engineers reviewing the TPS3851H30EDRBR datasheet, TPS3851H30EDRBR pinout, TPS3851H30EDRBR application, or TPS3851H30EDRBR equivalent, this page provides verified technical context, validated pin functions, confirmed timing parameters (tRST = 200 ms typ, tWD = 1600 ms typ with factory settings), and real-world application constraints including open-drain RESET/WDO drive capability and CWD capacitor-programmable watchdog configuration.

Technical Context

The TPS3851H30EDRBR implements a high-accuracy comparator-based undervoltage detection circuit with 0.5% hysteresis and factory-trimmed reference, ensuring stable reset assertion across temperature and supply variation. Its dual-output architecture separates RESET (system-wide reset) and WDO (watchdog fault flag) signals, allowing independent fault diagnosis without full system reboot.

Watchdog timing is configurable via CWD pin: unconnected or pulled up enables factory-programmed 1600 ms (typ) timeout (H30 variant), while external capacitor selection supports adjustable standard/extended timing modes. SET1 pin disables watchdog entirely, and MR input provides manual reset initiation with internal pullup.

Key Specifications

Pinout & Package

TPS3851H30EDRBR is housed in a 3.00 mm × 3.00 mm, 8-pin VSON package (DRB) with exposed thermal pad connected internally to GND. The package supports high-density PCB layouts and efficient thermal dissipation via soldered thermal pad connection to ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor with watchdog timer applications.

Compared with TPS3851H30EDRBR, TPS3851G33EDRBR offers identical timing and accuracy but narrower voltage coverage, while MAX6373KA29+T trades precision and configurability for reduced BOM count and lower unit cost in non-critical applications.

Availability

TPS3851H30EDRBR is available at Aetrix Electronics and suitable for WLAN access points, IP network cameras, string inverters, and portable medical devices requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for TPS3851H30EDRBR 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-grade ICs.

The TPS3851 product line delivers precision supervisory ICs with integrated watchdog timers for mission-critical embedded systems, targeting applications demanding tight voltage tolerance, extended temperature operation, and diagnostic flexibility.

FAQ

What is the undervoltage threshold accuracy of the TPS3851H30EDRBR over temperature?

The TPS3851H30EDRBR achieves ±0.8% undervoltage threshold (VITN) accuracy across the full operating junction temperature range of –40°C to +125°C. This specification is measured and guaranteed per TI's production test flow and applies to the H30 variant's support of 1.8 V to 5.0 V rails. The accuracy includes built-in hysteresis compensation and is validated using statistical process control on production lots.

How is the watchdog timeout configured on the TPS3851H30EDRBR?

The TPS3851H30EDRBR watchdog timeout is configured via the CWD pin: leaving it unconnected or pulling it up to VDD with a 10 kΩ resistor selects the factory-programmed 1600 ms typical timeout (H30 variant). Connecting a capacitor between CWD and GND enables user-adjustable timing using TI's standard or extended equations. SET1 must be high for watchdog operation; grounding SET1 disables it entirely.

What is the function of the WDO pin on the TPS3851H30EDRBR?

The WDO (Watchdog Output) pin on the TPS3851H30EDRBR is an open-drain output that asserts low for the duration of tRST (200 ms typ) when a watchdog timeout occurs - but only when RESET is high. When RESET is low (e.g., during undervoltage condition), WDO enters high-impedance state. This decoupling allows independent fault reporting without triggering full system reset.

Can the TPS3851H30EDRBR monitor multiple voltage rails simultaneously?

No, the TPS3851H30EDRBR monitors only the VDD supply rail - the same pin serves as both power input and monitored voltage source. It does not support multi-rail supervision. For systems requiring independent monitoring of 1.8 V, 3.3 V, and 5.0 V rails, multiple TPS3851H30EDRBR units or a multi-channel supervisor like TPS386000 would be required.

What package type and thermal considerations apply to the TPS3851H30EDRBR?

The TPS3851H30EDRBR uses the DRB package: a 3.00 mm × 3.00 mm, 8-pin VSON with exposed thermal pad. The pad is internally connected to GND and must be soldered to a large-area PCB ground plane to achieve specified RθJB = 25.8°C/W. Thermal design must account for maximum 125°C junction temperature under worst-case power dissipation (≤19 µA × 6.5 V ≈ 124 µW).