Texas Instruments TPS3838E18DBVT

Overview

TPS3838E18DBVT from Texas Instruments is a nano-power voltage supervisor IC with active-low open-drain RESET output, 1.71 V threshold voltage (V_IT), 10 ms / 200 ms selectable reset delay via CT pin, and 220 nA typical supply current - designed for undervoltage monitoring in ultra-low-power microcontroller systems powered by lithium coin cells or energy-harvesting sources.

For engineers reviewing the TPS3838E18DBVT datasheet, TPS3838E18DBVT pinout, TPS3838E18DBVT application, or TPS3838E18DBVT equivalent, key selection considerations include its open-drain output requiring external pull-up, precise 1.71 V supervision for 1.8 V rail monitoring, CT-configurable delay timing, manual reset capability, and operation across –40°C to 85°C industrial temperature range.

Technical Context

The TPS3838E18DBVT integrates a precision bandgap reference, comparator with hysteresis (V_HYS = 30 mV), refresh timer, and open-drain output stage. Its internal voltage divider sets a fixed 1.71 V threshold, validated over –40°C to 85°C with ±1.5% tolerance. The CT pin selects between two discrete delay modes: 10 ms (CT = GND) or 200 ms (CT = VDD), with no intermediate values supported.

Reset assertion occurs when VDD falls below V_IT or MR is pulled low; deassertion requires VDD > V_IT + V_HYS and MR high, followed by full delay time t_D. Propagation delay t_PHL is 10 µs typical from VDD or MR to RESET activation, ensuring fast fault response without compromising noise immunity.

Key Specifications

Pinout & Package

TPS3838E18DBVT is housed in a 5-pin SOT-23 (DBV) package, 2.90 mm × 1.60 mm body size, with gull-wing leads and RoHS-compliant NiPdAu finish. Pin 1 is VDD; pin 2 is GND; pin 3 is CT; pin 4 is MR; pin 5 is RESET. Pin 5 (RESET) is open-drain and requires external pull-up per Recommended Operating Conditions.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3836E18DBVT and MAX6375XR22+T, the TPS3838E18DBVT uniquely combines ultra-low 220 nA current, configurable delay, and open-drain output - enabling both long battery life and flexible reset architecture in space-constrained designs.

Availability

TPS3838E18DBVT is available at Aetrix Electronics and suitable for wearable health monitors, smart meter sensor nodes, industrial wireless sensors, and energy-harvesting edge nodes requiring stable component supply with guaranteed long-term manufacturability.

Supply support for TPS3838E18DBVT 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 delivering analog and embedded processing solutions, with leadership in power management, signal chain, and microcontrollers.

The TPS383x family was developed specifically for ultra-low-power voltage supervision in battery-critical applications - emphasizing nanoscale current consumption, precision thresholds, and minimal external component count for portable and energy-constrained systems.

FAQ

What is the exact threshold voltage of the TPS3838E18DBVT and how tightly is it specified?

The TPS3838E18DBVT has a nominal threshold voltage (V_IT) of 1.71 V, with a maximum deviation of ±1.5% over the full –40°C to 85°C operating temperature range. This specification is guaranteed by design and verified in production test, ensuring consistent 1.8 V rail supervision without calibration. The TPS3838E18DBVT achieves this accuracy using a trimmed internal voltage divider referenced to a stable bandgap.

Does the TPS3838E18DBVT require an external pull-up resistor on the RESET pin?

Yes, the TPS3838E18DBVT features an active-low open-drain RESET output and requires an external pull-up resistor to the desired logic-high voltage (e.g., 1.8 V or 3.3 V). The recommended value depends on rise time and bus loading but is typically 10 kΩ to 100 kΩ. This differs from the push-pull variants (e.g., TPS3836E18DBVT), which do not require external pull-ups.

How is the reset delay time selected on the TPS3838E18DBVT?

The reset delay time on the TPS3838E18DBVT is selected solely by the voltage applied to the CT pin: connecting CT to GND configures a 10 ms delay, while connecting CT to VDD configures a 200 ms delay. No external capacitor or resistor is needed. The TPS3838E18DBVT does not support intermediate or user-programmable delay values - only these two factory-characterized options.

Can the TPS3838E18DBVT monitor a 1.8 V supply rail reliably?

Yes, the TPS3838E18DBVT is explicitly designed for 1.8 V rail supervision, with a 1.71 V threshold and 30 mV hysteresis (V_HYS). This ensures the device asserts RESET before the 1.8 V rail drops below the minimum operating voltage of most 1.8 V MCUs and deasserts only after the rail recovers to ~1.74 V for the full delay period - preventing oscillation near the trip point.

What is the maximum supply voltage the TPS3838E18DBVT can tolerate on its VDD pin?

The TPS3838E18DBVT has an absolute maximum VDD rating of 7 V, as specified in Section 7.1 of the datasheet. However, its recommended operating range is 1.6 V to 6 V. Exceeding 7 V risks permanent damage. For systems with potential transients (e.g., automotive or industrial), TI recommends adding clamping protection or filtering ahead of the VDD pin to ensure compliance with this limit.