Texas Instruments TPS3808EG18DBVR

Overview

TPS3808EG18DBVR from Texas Instruments is a low-quiescent-current, programmable-delay supervisory circuit designed to monitor 1.8V power rails in embedded systems. It features a fixed 1.67V undervoltage threshold (±0.5% accuracy), 0.6μA typical supply current, 20ms/300ms selectable or capacitor-programmable reset delay (1.25ms–10s), and operates across –40°C to +125°C. It is used in DC-input BLDC motor drives to ensure safe microcontroller startup after power stabilization.

For engineers reviewing the TPS3808EG18DBVR datasheet, TPS3808EG18DBVR pinout, TPS3808EG18DBVR application, or TPS3808EG18DBVR equivalent, key selection criteria include its open-drain RESET output with 400mV VOL at 1mA, SENSE/VDD separation for accurate rail monitoring, MR input with 90kΩ internal pull-up, CT-pin-based delay configuration, and SOT-23-6 package compatibility with space-constrained industrial PCBs.

Technical Context

The TPS3808EG18DBVR implements a precision voltage comparator with 0.5% threshold accuracy referenced to an internal bandgap, enabling reliable detection of 1.8V rail collapse. Its reset assertion logic responds to either SENSE falling below 1.67V or MR pulled low, holding RESET active for a user-defined delay after both conditions clear.

Delay timing is controlled via the CT pin: open-circuit yields 20ms, resistor-to-VDD yields 300ms, and external capacitor (≥130pF) enables programmable delays up to 10s using a 220nA on-chip current source. The open-drain RESET output requires an external pull-up (10kΩ–1MΩ) and supports voltages up to 6V, decoupling reset signaling from VDD level.

Key Specifications

Pinout & Package

TPS3808EG18DBVR is housed in a compact 6-pin SOT-23 (DBV) package measuring 2.90mm × 1.60mm, optimized for high-density PCB layouts in space-constrained industrial modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar supervisory circuit applications.

Compared with TPS3808EG18DBVR, TPS3808G18DBVR offers identical supervision functionality at lower cost but without automotive qualification, while MAX6326LT18D2T trades programmability and MR support for ultra-compact size and higher quiescent current-making it viable only in space-constrained, non-battery applications.

Availability

TPS3808EG18DBVR is available at Aetrix Electronics and suitable for DC-input BLDC motor drives, electricity meters, and surgical equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TPS3808EG18DBVR 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 and embedded processing solutions, with over 90 years of innovation in power management, signal chain, and microcontrollers.

The TPS3808E product line was engineered specifically for ultra-low-power, high-accuracy voltage supervision in industrial and medical systems demanding extended temperature operation and flexible reset timing.

FAQ

What is the exact undervoltage threshold voltage of the TPS3808EG18DBVR?

The TPS3808EG18DBVR has a factory-set undervoltage threshold of 1.67V with ±0.5% accuracy over –40°C to +125°C. This value corresponds to nominal 1.8V rail monitoring and is specified in TI's SNVSCE0B datasheet Section 4 (Device Voltage Thresholds). The threshold is derived from a precision internal reference, eliminating need for external resistor dividers in standard 1.8V applications. TPS3808EG18DBVR does not support adjustable thresholds.

How is the reset delay time configured on the TPS3808EG18DBVR?

The reset delay time on TPS3808EG18DBVR is set via the CT pin: leaving CT open yields 20ms, connecting CT to VDD through a 40kΩ–200kΩ resistor yields 300ms, and connecting CT to GND through a capacitor (≥130pF) enables programmable delays from 1.25ms to 10s. The delay is generated by an internal 220nA current source charging the external capacitor. TPS3808EG18DBVR's CT pin must avoid stray capacitance to maintain timing accuracy.

Does the TPS3808EG18DBVR require external components for basic operation?

Yes - TPS3808EG18DBVR requires three external components for reliable operation: a 0.1μF ceramic capacitor on VDD, a pull-up resistor (10kΩ–1MΩ) on RESET, and optionally a resistor or capacitor on CT depending on desired delay. The MR pin may be left floating (due to internal 90kΩ pull-up) if manual reset is unused. No external components are needed for threshold setting, as TPS3808EG18DBVR uses a fixed 1.67V internal reference.

What is the maximum supply voltage the TPS3808EG18DBVR can tolerate on its VDD pin?

The TPS3808EG18DBVR supports VDD voltages from 1.7V to 6.0V per Absolute Maximum Ratings (Section 6.1). Operation above 6.0V risks permanent damage. Recommended operating range remains 1.7V–6.0V, and the device maintains full specification compliance-including 0.6μA quiescent current and 1.67V threshold accuracy-across this entire range. TPS3808EG18DBVR's VDD rating enables use with diverse supplies including 3.3V, 5V, and intermediate rails.

Can the TPS3808EG18DBVR monitor a voltage rail different from its own supply voltage?

Yes - TPS3808EG18DBVR features separate SENSE and VDD pins, allowing it to monitor a voltage rail independent of its supply. For example, it can be powered from a 3.3V rail (VDD) while supervising a 1.8V core supply (connected to SENSE). This isolation ensures accurate threshold detection regardless of VDD fluctuations, and is explicitly supported in TI's datasheet Section 5 (Pin Functions) and Figure 8-1. TPS3808EG18DBVR's SENSE input accepts 0–6V, making it compatible with rails both above and below VDD.