Analog Devices Inc. LTC2909IDDB-5#TRMPBF

Overview

LTC2909IDDB-5#TRMPBF from Analog Devices (formerly Linear Technology) is a precision triple-input supply monitor IC designed for system-level power integrity supervision in industrial and embedded applications. It features dual adjustable 0.5V-threshold inputs with pin-selectable polarity, a fixed 4.425V VCC UVLO threshold (±1.5% accuracy), 200ms internal reset timeout, and open-drain RST output. It operates down to 0.5V VCC and supports negative voltage monitoring via buffered 1V reference.

For engineers reviewing the LTC2909IDDB-5#TRMPBF datasheet, LTC2909IDDB-5#TRMPBF pinout, LTC2909IDDB-5#TRMPBF application, or LTC2909IDDB-5#TRMPBF equivalent, key selection considerations include input polarity configuration via SEL pin, VCC shunt regulation capability up to 6.5V, ultralow 50μA quiescent current, glitch-filtered comparators, and compatibility with 3mm × 2mm DFN-8 packaging for space-constrained designs.

Technical Context

The LTC2909IDDB-5#TRMPBF implements three independent voltage monitors: two adjustable inputs (ADJ1/ADJ2) with 0.5V nominal threshold and ±1.5% accuracy over –40°C to +85°C, plus a fixed VCC UVLO set to 4.425V (10% below 5V nominal). Polarity of each ADJ input is selected by the three-state SEL pin (VCC/Open/GND), enabling simultaneous positive UV/OV and negative UV/OV detection without external components.

Reset assertion is synchronized across all monitored rails; RST remains low until all valid inputs exceed their thresholds and the timeout period elapses. The TMR pin configures timeout mode: grounded for 200ms internal, capacitor-coupled for 9ms/nF external timing, or tied to VCC for comparator-mode bypass. A buffered 1.000V reference (±15mV, ±1mA drive) enables accurate offset-based negative rail monitoring.

Key Specifications

Pinout & Package

Package: 8-lead 3mm × 2mm plastic DFN (DDB) with exposed pad (Pin 9), rated for –40°C to +85°C operation and θJA = 76°C/W with PCB thermal pad connection.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar supply monitoring applications.

Compared with LTC2909CDDB-5#TRMPBF, the LTC2909IDDB-5#TRMPBF adds guaranteed operation at –40°C and 85°C-essential for automotive and outdoor industrial use. Versus TPS3808G33DBVR, it provides dual adjustable inputs, polarity flexibility, and negative rail capability, making it a complete replacement for multi-rail supervision where single-rail devices fall short.

Availability

LTC2909IDDB-5#TRMPBF is available at Aetrix Electronics and suitable for desktop computing, automotive body electronics, industrial PLCs, and network server power management requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC2909IDDB-5#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 LTC2909 product line delivers precision, low-power, multi-rail voltage supervision ICs optimized for reliability-critical systems where accurate UV/OV detection, negative rail support, and minimal quiescent current are mandatory design requirements.

FAQ

What is the guaranteed operating temperature range for LTC2909IDDB-5#TRMPBF?

The LTC2909IDDB-5#TRMPBF is specified for industrial temperature operation from –40°C to +85°C. This range is validated per the Absolute Maximum Ratings table and applies to all electrical characteristics including ADJ input threshold accuracy (±1.5%), VCC UVLO (4.425V ±1.5%), and quiescent current (50μA typical). The DFN-8 package with exposed pad achieves θJA = 76°C/W when thermally anchored to PCB copper.

How does the SEL pin configure polarity for ADJ1 and ADJ2 on LTC2909IDDB-5#TRMPBF?

The SEL pin on LTC2909IDDB-5#TRMPBF selects one of three polarity modes: tied to VCC sets both ADJ1 and ADJ2 to positive polarity (UV detection); tied to GND sets both to negative polarity (UV detection on negative rails); left open (high-impedance, <10μA leakage) configures ADJ1 positive and ADJ2 negative. This enables detection of combinations like +5V UV and –12V UV simultaneously without external logic.

Can LTC2909IDDB-5#TRMPBF monitor a single 5V supply for both undervoltage and overvoltage conditions?

Yes, LTC2909IDDB-5#TRMPBF can monitor one 5V supply for both UV and OV using three external resistors and the REF pin. Configure ADJ1 for UV (e.g., trip at 4.425V) and ADJ2 for OV (e.g., trip at 5.575V) with appropriate resistor dividers referenced to REF or GND. The SEL pin must be open to assign opposite polarities-ensuring RST asserts if either condition occurs.

What is the purpose of the buffered 1V reference (REF pin) on LTC2909IDDB-5#TRMPBF?

The REF pin on LTC2909IDDB-5#TRMPBF provides a precision 1.000V ±15mV buffered output capable of sourcing/sinking ±1mA. It serves as an offset reference for resistor dividers monitoring negative supplies-e.g., connecting ADJ2 between –12V and REF creates a 0.5V threshold at –11.5V, enabling accurate –12V UV detection. No external buffer or reference IC is needed.

Does LTC2909IDDB-5#TRMPBF require an external timing capacitor for basic operation?

No, LTC2909IDDB-5#TRMPBF does not require an external timing capacitor for basic operation. When the TMR pin is tied to GND, the device uses its internal 200ms reset timeout-eliminating the need for external components. Capacitors are only required when programmable timeout (e.g., 20ms with 2.2nF) or comparator mode (TMR = VCC) is desired.