Texas Instruments TPS386040RGPT

Overview

TPS386040RGPT from Texas Instruments is a quad supply voltage supervisor IC with adjustable delay and watchdog timer, featuring four independent supervisors (including one window comparator), 0.25% typical threshold accuracy, 11 μA typical quiescent current, and push-pull RESET/WDO outputs - used for reliable power-on reset and fault monitoring in FPGA, DSP, and microprocessor systems.

For engineers reviewing the TPS386040RGPT datasheet, TPS386040RGPT pinout, TPS386040RGPT application, or TPS386040RGPT equivalent, key selection considerations include its 20-pin VQFN package, programmable 1.4 ms–10 s reset delays per channel, support for negative voltage sensing via SENSE4L/SENSE4H + VREF, and push-pull output drive capability eliminating external pull-ups.

Technical Context

The TPS386040RGPT implements four independent supervisory circuits (SVS-1 to SVS-4), each with user-programmable undervoltage thresholds down to 0.4 V using external resistor dividers on SENSE pins; SVS-4 adds window-comparator functionality via dual inputs (SENSE4L for falling threshold, SENSE4H for rising threshold) and supports negative rail monitoring when paired with the 1.2 V VREF output.

It integrates a dedicated watchdog timer with WDI input and WDO output, where timeout occurs if no edge is detected within 600 ms (typical); reset delay timing is independently configured per channel via CTn pins using capacitors (220 pF–1000 nF) or fixed resistors, and MR input provides active-low manual reset only for SVS-1.

Key Specifications

Pinout & Package

TPS386040RGPT is housed in a 4.0 mm × 4.0 mm, 20-pin VQFN (RGP) package with exposed thermal pad, optimized for compact high-density PCB layouts and thermal performance (R_θJA = 46°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad voltage supervisor applications.

Compared with TPS386000RGPT, TPS386040RGPT eliminates pull-up components and improves drive strength; versus MAX6804HEUT+T, it adds a fourth supervisor channel, window detection, watchdog timer, and programmable delays - making it suitable for complex, safety-aware power architectures.

Availability

TPS386040RGPT is available at Aetrix Electronics and suitable for FPGA power sequencing, DSP/microcontroller reset management, analog signal chain monitoring, and negative voltage rail supervision requiring stable component supply across industrial, telecom, and embedded computing programs.

Supply support for TPS386040RGPT 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 for industrial, automotive, and communications markets.

The TPS3860x0 product line was designed specifically for high-accuracy, multi-rail power supervision in systems demanding precise voltage margining, flexible sequencing, and hardware-based fault recovery - targeting FPGA, ASIC, and DSP platforms.

FAQ

What is the function of the VREF pin on the TPS386040RGPT?

The VREF pin on the TPS386040RGPT provides a precision 1.20 V ±20 mV reference output, intended solely for sourcing current into resistor networks. It enables accurate negative-voltage supervision when connected with SENSE4H in an inverting configuration - for example, monitoring –3.3 V using a two-resistor divider. The TPS386040RGPT datasheet specifies that VREF must not be loaded above 0.2 mA or connected to voltages exceeding 1.2 V.

How does the watchdog timer operate in the TPS386040RGPT?

The watchdog timer in the TPS386040RGPT is triggered by edges on the WDI pin; a rising or falling transition every 600 ms (typical) prevents timeout. If no edge occurs within this period, WDO asserts low. The timer starts counting after RESET1 is released, and WDI must be driven actively - floating or static states cause timeout. This behavior is fully documented in the TPS386040RGPT switching characteristics table and Figure 5 of the datasheet.

Can the TPS386040RGPT monitor negative supply voltages?

Yes, the TPS386040RGPT can monitor negative supply voltages using SENSE4H in combination with the VREF pin. By connecting VREF to one end of a resistor divider and the negative rail to the other, SENSE4H senses the inverted, level-shifted voltage. When the negative rail drops below its threshold (e.g., –3.3 V), the resulting voltage at SENSE4H exceeds 400 mV, triggering RESET4. This method is explicitly described in the TPS386040RGPT datasheet Section 9.1 and Figure 34.

What is the difference between TPS386040RGPT and TPS386000RGPT?

The primary difference is output driver topology: TPS386040RGPT features push-pull RESETn and WDO outputs, while TPS386000RGPT uses open-drain outputs requiring external pull-up resistors. All supervision functions, pinout, timing, and electrical specifications (except output structure) are identical. The TPS386040RGPT simplifies design by removing four pull-up resistors and enabling direct logic-level interfacing - confirmed in the TPS386040RGPT Pin Functions table and Features list.

What package type and dimensions does the TPS386040RGPT use?

The TPS386040RGPT uses a 20-pin VQFN package (RGP variant) with nominal body dimensions of 4.0 mm × 4.0 mm and 0.5 mm pitch. It includes an exposed thermal pad that must be soldered to a ground plane for optimal thermal performance (R_θJB = 22.4°C/W). This package is specified in the TPS386040RGPT Device Information table and Mechanical section of the official datasheet.