Analog Devices Inc. LTC2917HDDB-A1#TRMPBF

Overview

LTC2917HDDB-A1#TRMPBF from Analog Devices (formerly Linear Technology) is a high-temperature voltage supervisor IC with 9 selectable nominal thresholds (12V to ADJ), ±1.5% threshold accuracy over –40°C to 125°C, 30μA quiescent current, and an adjustable watchdog timer. It operates from 1.5V to 5.5V supply and supports windowed watchdog (B-version only) - this A1 variant uses standard watchdog timing. It is used in automotive control systems requiring reliable power-on reset and brownout detection under extreme thermal conditions.

For engineers reviewing the LTC2917HDDB-A1#TRMPBF datasheet, LTC2917HDDB-A1#TRMPBF pinout, LTC2917HDDB-A1#TRMPBF application, or LTC2917HDDB-A1#TRMPBF equivalent, key selection criteria include its 10-lead DFN (3mm × 2mm) package, –40°C to 125°C operating range, internal 200ms/400μs reset timeout options, 1.5% threshold tolerance guarantee, and compatibility with 1.8V–5V logic interfaces via open-drain RST output.

Technical Context

The LTC2917HDDB-A1#TRMPBF implements a precision comparator-based voltage monitor with three-state SEL1/SEL2 inputs selecting one of nine nominal thresholds (12V, 5V, 3.3V, 2.5V, 1.8V, 1.5V, 1.2V, 1.0V, or ADJ=0.5V), and a TOL input setting –5%/–10%/–15% tolerance bands. Its internal 6.2V shunt regulator enables operation from supplies up to 12V when paired with a series resistor on VCC.

It features glitch-filtered reset assertion with tUV ≤ 150μs response to VM undervoltage, guaranteed RST assertion down to VCC ≥ 0.8V, and dual-mode watchdog timing: internal ~1.6s upper boundary (WT tied to VCC) or external capacitor-adjustable (72ms/nF). This A1 version lacks windowed watchdog - only falling-edge WDI monitoring applies without lower-bound enforcement.

Key Specifications

Pinout & Package

Package: 10-lead (3mm × 2mm) plastic DFN with exposed pad (pin 11, optional GND connection).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326UT29D3+T and TPS3808G33DBVR, the LTC2917HDDB-A1#TRMPBF offers field-programmable thresholds, –40°C to 125°C operation, integrated watchdog, and ADJ mode - making it uniquely suited for multi-rail automotive and industrial systems requiring design flexibility and extended temperature resilience.

Availability

LTC2917HDDB-A1#TRMPBF is available at Aetrix Electronics and suitable for automotive engine control units, industrial programmable logic controllers, optical network line cards, and medical infusion pumps requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC2917HDDB-A1#TRMPBF 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, Inc. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC2917 product line was developed by Linear Technology (acquired by ADI in 2017) specifically for high-reliability power supervision in harsh environments - emphasizing precision threshold accuracy, wide temperature operation, and integrated watchdog functionality for safety-critical embedded systems.

FAQ

What is the maximum supply voltage the LTC2917HDDB-A1#TRMPBF can tolerate on its VCC pin?

The LTC2917HDDB-A1#TRMPBF has an absolute maximum VCC rating of 5.7V for direct connection. However, its internal 6.2V shunt regulator allows operation from higher supplies (e.g., 12V automotive battery) when a series current-limiting resistor is used to keep VCC pin current ≤5mA. Without that resistor, exceeding 5.7V risks violating terminal current limits and damaging the device. Always refer to the Absolute Maximum Ratings table and Figure 3 in the datasheet for proper high-voltage implementation.

Does the LTC2917HDDB-A1#TRMPBF support windowed watchdog functionality?

No, the LTC2917HDDB-A1#TRMPBF does not support windowed watchdog. The "A1" suffix denotes the A-version, which implements standard watchdog timing - RST asserts only if WDI fails to toggle within the upper boundary (tWDU). The windowed watchdog (requiring both upper and lower boundaries) is exclusive to B-version parts like LTC2917HDDB-B1#TRMPBF. For high-reliability applications needing edge-rate validation, the B1 variant must be selected.

How do I configure the LTC2917HDDB-A1#TRMPBF to monitor a 9V supply with –15% tolerance?

To monitor 9V @ –15%, configure SEL1=GND, SEL2=GND (selecting ADJ=0.5V nominal), and TOL=GND (–15% tolerance). Then connect VM to a resistive divider from the 9V rail to GND, sized so VM = 0.5V at exactly 9V. Using R1 = 51.1kΩ and R2 = 866kΩ yields VM = 0.5V at 9V nominal, resulting in a trip point of 7.65V (9V × 0.85). This configuration leverages the LTC2917HDDB-A1#TRMPBF's ADJ mode and guaranteed ±1.5% accuracy over temperature.

Can the RST output of the LTC2917HDDB-A1#TRMPBF drive a 5V logic input directly?

Yes, the RST output is open-drain and rated for voltages up to 7.5V on the pin, so it can safely interface with 5V logic when pulled up to 5V via an external resistor (e.g., 10kΩ). The VOL specification guarantees ≤0.4V at IRST = 2.5mA when VCC = 3.3V, ensuring solid low-level signaling. However, ensure the 5V pull-up does not exceed the 7.5V absolute maximum rating on RST and that sink current remains within datasheet limits for your chosen pull-up value and logic family.

What is the purpose of the exposed pad on the LTC2917HDDB-A1#TRMPBF DFN package?

The exposed pad (pin 11) on the LTC2917HDDB-A1#TRMPBF's 10-lead DFN package is thermally and electrically connected to the die substrate. It may be left unconnected or soldered to a PCB ground plane to improve thermal dissipation and reduce θJA from 43°C/W to lower values. While optional for basic functionality, grounding the pad enhances reliability in high-temperature automotive applications by lowering junction temperature - a recommended practice for sustained 125°C operation.