Texas Instruments TPS3840DL20DBVR

Overview

TPS3840DL20DBVR from Texas Instruments is a nano-power, high-input-voltage supervisor IC with active-low open-drain reset output, 2.0V fixed threshold (±1.5% max), 300nA typical supply current, and programmable reset delay up to 6.2s via external capacitor on CT pin - used for reliable power-on-reset and brownout detection in battery-powered industrial sensors and smart meters.

For engineers reviewing the TPS3840DL20DBVR datasheet, TPS3840DL20DBVR pinout, TPS3840DL20DBVR application, or TPS3840DL20DBVR equivalent, key selection criteria include its 1.5V–10V operating range, 220µs startup delay, built-in hysteresis (100mV typ.), MR input logic compatibility, and SOT-23-5 package footprint for space-constrained designs.

Technical Context

The TPS3840DL20DBVR implements a precision bandgap-referenced comparator monitoring VDD against a factory-trimmed 2.0V negative-going threshold (VIT−), with hysteresis (VIT+) generated internally to prevent chatter during slow-rising/falling supply transitions. Its glitch-immune MR input accepts logic-level signals down to 600mV (V_{MR_L}) and features internal 100kΩ pull-up.

Reset assertion occurs when VDD falls below 2.0V or MR is pulled low; deassertion requires VDD to rise above 2.1V (2.0V + 100mV hysteresis) *and* expiration of the user-programmed t_D delay (50µs–6.2s). The CT pin integrates a 500kΩ internal resistor (typ.) to form an RC timing network with external capacitance.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90mm × 1.60mm footprint, surface-mount, lead-free, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3840PL20DBVR, the TPS3840DL20DBVR offers lower system-level leakage and voltage-level flexibility via external pull-up, while MAX6326LT20D3+ trades programmability and nano-power for lower unit cost and guaranteed reset duration - making TPS3840DL20DBVR optimal for battery longevity and design adaptability.

Availability

TPS3840DL20DBVR is available at Aetrix Electronics and suitable for smart metering, portable safety instrumentation, and industrial PLC modules requiring stable component supply, long-term lifecycle support, and guaranteed nano-power performance.

Supply support for TPS3840DL20DBVR 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 personal electronics markets.

The TPS3840 family was designed specifically for ultra-low-power, high-voltage supervision in battery-backed and energy-harvesting systems - emphasizing precision threshold accuracy, minimal quiescent current, and flexible reset timing.

FAQ

What is the exact threshold voltage of the TPS3840DL20DBVR?

The TPS3840DL20DBVR has a factory-trimmed fixed negative-going input threshold (VIT−) of 2.0V, with accuracy of ±1.5% maximum over –40°C to +125°C. This value is laser-trimmed during production and does not require external calibration or adjustment in circuit design.

Can the TPS3840DL20DBVR monitor a 24V rail directly?

No - the TPS3840DL20DBVR absolute maximum VDD rating is 12V. To supervise a 24V rail, use a precision resistor divider to scale the voltage down to ≤10V at the VDD pin, ensuring the divider's Thevenin resistance stays within recommended limits (<100kΩ) to avoid threshold error.

How do I configure the reset delay time for the TPS3840DL20DBVR?

Connect a capacitor between the CT pin (Pin 5) and GND. With no capacitor, t_D = 50µs (min). A 100nF capacitor yields ~62ms; 1µF gives ~620ms; 10µF achieves ~6.2s (max). The relationship follows t_D ≈ 618937 × C_CT + 50µs, where C_CT is in farads.

Does the TPS3840DL20DBVR require an external pull-up resistor on the RESET pin?

Yes - the TPS3840DL20DBVR features an open-drain active-low RESET output (Pin 1), which must be pulled up to a valid logic voltage (e.g., VDD or another supply) using an external resistor. Typical values range from 10kΩ to 100kΩ depending on speed and drive strength requirements.

What is the purpose of the MR pin on the TPS3840DL20DBVR?

MR (Pin 4) is an active-low manual reset input that allows external logic (e.g., MCU GPIO) to force a system reset asynchronously. Pulling MR low for >300ns asserts RESET; releasing MR allows RESET to deassert only after VDD rises above 2.1V *and* the programmed t_D delay expires - ensuring deterministic recovery timing.