Texas Instruments TPS3780BDRYT

Overview

TPS3780BDRYT from Texas Instruments is a dual-channel, open-drain voltage detector IC designed for precision rail monitoring in low-power systems. It features 5% hysteresis, ±1% V_IT+ accuracy over –40°C to +125°C, 2 µA typical quiescent current, and operates from 1.5 V to 6.5 V supply. It is used to assert reset or enable signals for microcontrollers and power supplies during undervoltage conditions.

For engineers reviewing the TPS3780BDRYT datasheet, TPS3780BDRYT pinout, TPS3780BDRYT application, or TPS3780BDRYT equivalent, key selection criteria include its open-drain output architecture (supporting independent pull-up to 6.5 V), factory-set 5% hysteresis, adjustable detection threshold down to 1.2 V via external resistor divider, and µSON-6 package compatibility with space-constrained portable and industrial designs.

Technical Context

The TPS3780BDRYT implements two independent high-accuracy comparators with internal reference and fixed 5% hysteresis - meaning V_IT– = V_IT+ × (1 − 0.05). Its SENSE1/SENSE2 inputs accept voltages up to 6.5 V regardless of VDD, enabling monitoring of rails higher than the device supply. Each channel asserts its respective open-drain output (OUT1/OUT2) low when input falls below V_IT–, and releases it (high-impedance) when input rises above V_IT+.

Startup delay is fixed at 570 µs after VDD crosses V_DD(min); propagation delays are 5.5 µs (rising) and 10 µs (falling). The device includes built-in immunity to brief glitches via hysteresis and supports wired-AND logic combining of outputs - critical for system-level reset coordination in multi-rail power architectures.

Key Specifications

Pinout & Package

TPS3780BDRYT is housed in a 1.45 mm × 1.00 mm, 6-pin µSON (DRY) package with wettable flanks for automated optical inspection. Thermal resistance R_θJA is 306.7°C/W, suitable for compact PCB layouts with limited copper area.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel voltage detector applications.

Compared with TPS3780CDRYT, the TPS3780BDRYT offers tighter hysteresis for improved threshold resolution in clean power environments; compared with MAX6315US29D3+T, it delivers true dual-rail supervision in half the footprint with configurable thresholds - reducing BOM count and layout complexity in multi-supply systems.

Availability

TPS3780BDRYT is available at Aetrix Electronics and suitable for microcontroller power sequencing, portable medical device monitoring, industrial PLC I/O module supervision, and solid-state drive (SSD) power-rail validation requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TPS3780BDRYT 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 expertise in precision sensing and power integrity solutions.

The TPS37xx family was engineered specifically for high-accuracy, low-quiescent-current dual-rail monitoring in space- and power-constrained applications - targeting portable electronics, industrial automation, and automotive subsystems demanding reliable voltage supervision.

FAQ

What is the factory-set hysteresis value for the TPS3780BDRYT?

The TPS3780BDRYT has a factory-set hysteresis of exactly 5%, meaning V_IT– = V_IT+ × 0.95. This value is laser-trimmed during production and remains stable across –40°C to +125°C. It is not user-adjustable and differs from other variants in the TPS3780 series (e.g., TPS3780CDRYT = 10%). The 5% hysteresis balances noise immunity and threshold resolution for general-purpose rail monitoring.

Can the TPS3780BDRYT monitor a 5-V rail while powered from a 3.3-V supply?

Yes, the TPS3780BDRYT can monitor a 5-V rail while operating from a 3.3-V VDD supply. Its SENSE1 and SENSE2 inputs tolerate voltages up to 6.5 V independent of VDD, enabling direct connection to higher-voltage rails via a resistor divider. For a 5-V rail, use a standard 1% divider (e.g., 1.13 MΩ/787 kΩ) to scale to ~1.194 V at the SENSE pin - matching the nominal V_IT+ threshold.

What is the minimum pull-up resistor value required for the TPS3780BDRYT's open-drain outputs?

The minimum pull-up resistor value for the TPS3780BDRYT's OUT1/OUT2 is determined by V_OL ≤ 0.25 V at I_SINK = 2 mA (for VDD ≥ 2.7 V). Using Ohm's Law: R_PU(min) = (V_PULLUP − V_OL) / I_SINK. With 3.3-V pull-up, R_PU(min) ≈ (3.3 − 0.25) / 0.002 = 1.525 kΩ. TI recommends 10 kΩ as a robust default; values between 1.5 kΩ and 100 kΩ are supported per datasheet R_PU specification (1.5–10,000 kΩ).

Does the TPS3780BDRYT require an input bypass capacitor on the SENSE pins?

The TPS3780BDRYT does not require a bypass capacitor on SENSE1 or SENSE2 under normal conditions. Its built-in 5% hysteresis provides inherent noise immunity. However, for extremely noisy environments (e.g., motor drives or switch-mode power supply feedback paths), TI recommends adding a 1-nF to 10-nF ceramic capacitor directly at the SENSE pin to suppress high-frequency transients - as noted in Section 8.3.1 of the SBVS250 datasheet.

How does the TPS3780BDRYT behave during power-up when VDD ramps slowly?

During slow VDD ramp-up (<200 mV/ms), the TPS3780BDRYT may assert OUT1/OUT2 high erroneously if SENSEx voltage rises before VDD reaches V_DD(min). To prevent this, TI specifies that SENSEx lines must be held ≤ V_IT– until VDD exceeds V_DD(min), or sequenced after VDD. Once VDD crosses V_DD(min), a fixed 570-µs startup delay ensures outputs reflect true SENSE states - documented in Section 8.4.1 and Figure 15 of SBVS250.