Analog Devices Inc. LTC2918HMS-A1#TRPBF

Overview

LTC2918HMS-A1#TRPBF from Analog Devices (formerly Linear Technology) is a high-temperature voltage supervisor IC with manual reset input, 9 selectable supply thresholds (12V to ADJ/0.5V), fixed –5% tolerance, and adjustable watchdog/reset timers. It operates from 1.5V to 5.5V supply, consumes 30μA quiescent current, guarantees ±1.5% threshold accuracy over –40°C to 125°C, and delivers reliable reset assertion for automotive control systems and industrial embedded power monitoring.

For engineers reviewing the LTC2918HMS-A1#TRPBF datasheet, LTC2918HMS-A1#TRPBF pinout, LTC2918HMS-A1#TRPBF application, or LTC2918HMS-A1#TRPBF equivalent, key selection criteria include its MSOP-10 package, –40°C to 125°C operating range, internal 200ms reset timeout (RT = VCC), 1.6s watchdog upper boundary (WT = VCC), manual reset (MR) interface, and guaranteed RST assertion down to VCC ≥ 0.8V.

Technical Context

The LTC2918HMS-A1#TRPBF implements a dual-timer architecture: an adjustable reset timer controlled via RT pin (internal 200ms default when tied to VCC) and a windowed watchdog timer managed by WT and WDI pins (1.6s upper bound when WT = VCC). Its VM comparator uses a precision reference with ±1.5% threshold accuracy across temperature, and glitch immunity ensures robust operation against transients up to 150μs at 5% over-threshold.

Unlike the LTC2917, the LTC2918HMS-A1#TRPBF integrates a dedicated MR input with internal 100kΩ pull-up, enabling push-button reset without external components. The fixed –5% tolerance eliminates TOL pin usage, simplifying configuration versus the LTC2917 family, while maintaining identical 9-threshold selection logic via SEL1/SEL2 three-state inputs.

Key Specifications

Pinout & Package

Package: 10-Lead MSOP (3mm × 3mm), RoHS-compliant, rated for –40°C to 125°C operation. Exposed pad optional for thermal enhancement.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326US29D3+ and TPS3808G33DBVR, the LTC2918HMS-A1#TRPBF offers unique value in configurable thresholds, integrated manual reset, and programmable watchdog timing-critical for complex, multi-rail automotive and industrial systems requiring design flexibility and high-temperature reliability.

Availability

LTC2918HMS-A1#TRPBF is available at Aetrix Electronics and suitable for automotive control systems, industrial PLCs, medical infusion pumps, and telecom base station power sequencing requiring stable component supply across extended temperature ranges.

Supply support for LTC2918HMS-A1#TRPBF 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

Analog Devices (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors.

The LTC2918 belongs to Linear's precision power supervision product line, designed specifically for mission-critical applications demanding guaranteed operation to 125°C, ±1.5% threshold accuracy, and robust glitch immunity in harsh environments.

FAQ

What is the maximum supply voltage the LTC2918HMS-A1#TRPBF can tolerate on its VCC pin?

The LTC2918HMS-A1#TRPBF features an internal 6.2V shunt regulator on the VCC pin. When supplied above 5.7V, a series current-limiting resistor must be used to restrict VCC pin current to ≤5mA. Absolute maximum VCC voltage is 5.7V without external protection; with proper resistor sizing, it safely supervises 12V or higher rails-common in automotive and industrial applications. The LTC2918HMS-A1#TRPBF datasheet specifies this shunt behavior explicitly in Absolute Maximum Ratings.

Does the LTC2918HMS-A1#TRPBF support windowed watchdog functionality?

No, the LTC2918HMS-A1#TRPBF is the "A" version and implements a standard watchdog timer with only an upper boundary timeout (e.g., 1.6s when WT = VCC). Windowed watchdog-requiring both upper and lower boundaries-is exclusive to "B" versions (e.g., LTC2918HMS-B1#TRPBF). The LTC2918HMS-A1#TRPBF responds to any WDI edge before timeout expiration; it does not enforce minimum pulse period or falling-edge-only detection.

How do I configure the LTC2918HMS-A1#TRPBF to monitor a 1.8V supply?

To monitor 1.8V with the LTC2918HMS-A1#TRPBF, set SEL1 = Open and SEL2 = Open (per Table 1 in the datasheet). This selects the 1.8V nominal threshold with fixed –5% tolerance, resulting in a guaranteed trip point of 1.71V ±1.5% (1.683V to 1.737V). No external resistors are needed. The LTC2918HMS-A1#TRPBF then asserts RST low when VM falls below this range and holds it for the configured reset timeout (e.g., 200ms if RT = VCC).

Can the MR pin of the LTC2918HMS-A1#TRPBF be left unconnected?

Yes, the MR pin of the LTC2918HMS-A1#TRPBF may be left unconnected. It has an internal 100kΩ pull-up resistor to VCC, ensuring a logic-high default state that disables manual reset. Leaving MR open is electrically safe and functionally equivalent to tying it to VCC. Only connect MR to GND (via switch or driver) when active manual reset is required. The LTC2918HMS-A1#TRPBF specification confirms this in the Pin Functions section.

What is the minimum VCC voltage required for valid RST assertion in the LTC2918HMS-A1#TRPBF?

The LTC2918HMS-A1#TRPBF guarantees RST assertion for VCC ≥ 0.8V, per Electrical Characteristics table (VCC(MIN)). Below 0.8V, RST behavior is undefined. Between 0.8V and 1.5V (UVLO threshold), RST remains asserted low regardless of VM state-ensuring reset during brown-out conditions. Once VCC exceeds 1.5V, the supervisor becomes fully functional and RST release depends on VM and timer settings. This 0.8V guarantee is critical for fail-safe operation in low-VCC scenarios.