Texas Instruments TPS3123J18DBVR

Overview

TPS3123J18DBVR from Texas Instruments is an ultra-low-voltage processor supervisory IC with 1.62 V nominal reset threshold (V_IT–), 180 ms power-on reset delay, manual reset input (MR), and watchdog timer (WDI) functionality. It monitors 1.8 V supply rails in DSP and microprocessor systems, asserts active-low RESET during undervoltage or watchdog timeout, and operates down to 0.9 V supply voltage. Designed for battery-powered portable equipment and industrial automation.

For engineers reviewing the TPS3123J18DBVR datasheet, TPS3123J18DBVR pinout, TPS3123J18DBVR application, or TPS3123J18DBVR equivalent, key selection criteria include its fixed 1.62 V threshold tolerance (±0.06 V), 14 µA typical supply current at 0.9 V, SOT-23-5 package compatibility, and integrated MR/WDI supervision-critical for fail-safe embedded control and always-on infrastructure.

Technical Context

The TPS3123J18DBVR implements a precision voltage comparator with internal hysteresis (20 mV at 1.62 V threshold) and a fixed 180 ms reset delay timer triggered when V_DD rises above V_IT+. Its watchdog timer times out after 0.8–2.1 s if WDI transitions are missed, retriggering RESET for system recovery.

It features a dedicated manual reset input (MR) that forces active-low RESET independently of V_DD level or watchdog state, and uses push-pull output topology-enabling direct interface with logic without external pull-up resistors. All functions operate across –40°C to +85°C.

Key Specifications

Pinout & Package

TPS3123J18DBVR is housed in a 5-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 mm, with standard lead finish (NiPdAu/Sn), RoHS-compliant, and MSL Level-1 rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3123J12DBVR, the TPS3123J18DBVR provides higher threshold accuracy for 1.8 V rails, while TPS3124J18DBVR offers identical supervision capability with inverted reset polarity-making both viable alternatives depending on voltage target and host interface requirements.

Availability

TPS3123J18DBVR is available at Aetrix Electronics and suitable for portable electronics, industrial edge controllers, wireless baseband modules, and building automation gateways requiring stable component supply across extended production lifecycles.

Supply support for TPS3123J18DBVR 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 microcontroller technologies.

The TPS312x family was designed specifically for ultra-low-voltage processor supervision in battery-constrained and industrial systems-integrating reset timing, manual reset, and watchdog functionality into a single 5-pin SOT-23 package.

FAQ

What is the exact reset threshold voltage range for TPS3123J18DBVR?

The TPS3123J18DBVR has a guaranteed negative-going input threshold voltage (V_IT–) range of 1.56 V to 1.68 V at TA = –40°C to +85°C, with a typical value of 1.62 V. This 1.8 V–10% specification ensures precise supervision of 1.8 V supply rails while accommodating manufacturing variance and temperature drift. The device also includes 20 mV of built-in hysteresis to prevent chatter near the threshold.

Does TPS3123J18DBVR support active-high reset output?

No, TPS3123J18DBVR provides only an active-low push-pull RESET output. Devices with active-high output in the same family include TPS3124J18DBVR and TPS3125J18DBVR. The TPS3123J18DBVR's RESET pin drives low during undervoltage, manual reset assertion, or watchdog timeout-and returns high after the 180 ms delay expires. This matches standard reset input requirements for most ARM and RISC-V microcontrollers.

How does the watchdog timer in TPS3123J18DBVR function?

The TPS3123J18DBVR watchdog timer triggers RESET if the WDI pin remains static (high or low) beyond 0.8–2.1 s. A rising or falling edge on WDI resets the timer. During timeout, RESET asserts for the full 100–260 ms delay period. This behavior detects software hangs in real-time systems like industrial controllers. Unlike windowed watchdogs, it requires only periodic toggling-not strict timing windows.

Can TPS3123J18DBVR operate below 1.0 V supply voltage?

Yes, TPS3123J18DBVR is fully specified down to 0.9 V supply voltage (V_DD). At 0.9 V, it draws 14 µA typical supply current and maintains functional MR input and RESET output behavior. However, RESET output validity requires V_DD ≥ 0.9 V; below this, the output state is undefined. This enables use in ultra-low-power wake-up supervisors and energy-harvesting applications.

What package type and footprint does TPS3123J18DBVR use?

TPS3123J18DBVR uses the SOT-23-5 (DBV) package: a 5-pin surface-mount package with 2.90 mm × 1.60 mm body size, 0.95 mm height, and standard 0.95 mm pin pitch. It is RoHS-compliant, has NiPdAu/Sn lead finish, and carries MSL Level-1 (unlimited floor life at ≤30°C/60% RH). The pinout is standardized across the TPS312x family for drop-in compatibility.