Texas Instruments TPS3851H50EDRBT

Overview

TPS3851H50EDRBT from Texas Instruments is a precision voltage supervisor IC with integrated watchdog timer, designed for system-level power integrity monitoring in microcontroller-based applications. It delivers 0.8% undervoltage threshold accuracy (–40°C to +125°C), 200 ms reset timeout (±15%), and user-programmable or factory-set watchdog timeouts up to 1.6 s - enabling reliable startup and fault recovery in industrial and connected devices.

For engineers reviewing the TPS3851H50EDRBT datasheet, TPS3851H50EDRBT pinout, TPS3851H50EDRBT application, or TPS3851H50EDRBT equivalent, this device supports tight-tolerance rail supervision (1.8V–5.0V), offers open-drain RESET/WDO outputs with 0.5% hysteresis, and integrates manual reset (MR), watchdog disable (SET1), and capacitor-programmable timing (CWD) for flexible system-level reset architecture design.

Technical Context

The TPS3851H50EDRBT implements a high-accuracy comparator-based undervoltage detection circuit with 0.8% VITN tolerance over full temperature range and 0.5% hysteresis, ensuring stable reset assertion without chatter near threshold. Its dual-output architecture separates RESET (system reset) and WDO (watchdog fault flag), allowing independent fault diagnosis without full system reboot.

Watchdog timing is configurable via CWD pin: unconnected or pulled-up enables factory-programmed 1.6 s (standard) or 200 ms (extended) timeouts; external capacitor enables continuous adjustment (0.7 ms to 77 s). SET1 pin disables watchdog entirely, and MR provides synchronous manual reset initiation - all operating within 1.6V–6.5V supply range and –40°C to +125°C junction temperature.

Key Specifications

Pinout & Package

TPS3851H50EDRBT is housed in a thermally enhanced 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 heat dissipation in compact designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3851H50EDRBT, the G50 variant offers identical performance and drop-in replacement capability, while the MAX6369KA29+T sacrifices programmability and diagnostic granularity for simpler fixed-function supervision - making it suitable only for cost-sensitive, single-rail applications without advanced fault isolation needs.

Availability

TPS3851H50EDRBT is available at Aetrix Electronics and suitable for WLAN access points, wireless security cameras, IP network cameras, string inverters, and blood pressure monitors requiring stable component supply across extended temperature and long product lifecycles.

Supply support for TPS3851H50EDRBT 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 since 1930.

The TPS3851 family was engineered specifically for high-reliability embedded systems requiring simultaneous precision rail monitoring and intelligent fault detection - targeting applications where traditional supervisors lack diagnostic depth or timing flexibility.

FAQ

What is the undervoltage threshold voltage for TPS3851H50EDRBT?

The TPS3851H50EDRBT is configured for a nominal 4.8 V undervoltage threshold (VITN), with ±0.8% accuracy over –40°C to +125°C. This corresponds to a guaranteed trip range of 4.7616 V to 4.8384 V at 25°C, and remains within ±0.8% across full temperature range per SBVS300B datasheet Section 5.5.

Does TPS3851H50EDRBT support both factory-programmed and user-adjustable watchdog timeouts?

Yes, TPS3851H50EDRBT supports both modes. With CWD unconnected or pulled up via 10 kΩ to VDD, it uses factory-programmed timeouts: 1.6 s (standard) or 200 ms (extended). Connecting a capacitor between CWD and GND enables continuous adjustment from 0.7 ms to 77 s using TI's published timing equations.

What is the function of the SET1 pin on TPS3851H50EDRBT?

The SET1 pin on TPS3851H50EDRBT controls watchdog enable/disable functionality. When SET1 is grounded, the watchdog timer is fully disabled and WDI input is ignored. When SET1 is high, watchdog operates normally. This allows safe firmware development and field updates without unintended timeouts.

Can TPS3851H50EDRBT monitor multiple voltage rails simultaneously?

No, TPS3851H50EDRBT monitors only the VDD supply rail. Its undervoltage detection is applied directly to the VDD pin - it does not include auxiliary sense inputs or multi-rail tracking capability. For multi-rail supervision, multiple TPS3851H50EDRBT units or a dedicated multi-channel supervisor like TPS3808G33 would be required.

What package type and thermal considerations apply to TPS3851H50EDRBT?

TPS3851H50EDRBT uses the DRB package: an 8-pin VSON measuring 3.00 mm × 3.00 mm with exposed thermal pad. The pad must be soldered to a large-area PCB ground plane to achieve specified RθJB = 25.8°C/W. Thermal design must account for max 150°C junction rating and ensure adequate copper area beneath the pad per TI's SZZA039 application note.