Analog Devices Inc. LTC2909ITS8-5#TRMPBF

Overview

LTC2909ITS8-5#TRMPBF from Analog Devices (formerly Linear Technology) is a precision triple-input voltage supervisor IC designed for system-level power monitoring in industrial and embedded applications. It features dual adjustable 0.5V-threshold inputs with ±1.5% accuracy over temperature, a fixed 4.425V VCC UVLO threshold, 200ms internal reset timeout, and open-drain RST output - enabling robust undervoltage/overvoltage detection for 5V logic rails, core supplies, and negative-bias rails.

For engineers reviewing the LTC2909ITS8-5#TRMPBF datasheet, LTC2909ITS8-5#TRMPBF pinout, LTC2909ITS8-5#TRMPBF application, or LTC2909ITS8-5#TRMPBF equivalent, key selection considerations include input polarity configuration via SEL pin, buffered 1V reference for negative-supply offset, 50μA quiescent current, TSOT-23-8 package compatibility, and guaranteed 0.5V reset assertion down to VCC = 0.5V.

Technical Context

The LTC2909ITS8-5#TRMPBF implements three independent comparators: two adjustable-input channels (ADJ1/ADJ2) with 0.5V nominal thresholds and one fixed VCC UVLO monitor set at 4.425V (±1.5%). Polarity of ADJ1/ADJ2 is selected via three-state SEL pin (VCC/Open/GND), enabling configurable UV/OV detection on positive or negative supplies. The buffered 1V REF output supports offset-based negative-rail monitoring without external components.

Reset timing is controlled by TMR pin state: grounded for 200ms internal timeout, capacitor-connected for programmable delay (9ms/nF), or tied to VCC for comparator-mode bypass. Propagation delays are ≤500μs, and glitch rejection is achieved via internal low-pass filtering - not hysteresis - preserving threshold accuracy while suppressing transients.

Key Specifications

Pinout & Package

Package: 8-lead TSOT-23 (3mm × 1.75mm), RoHS-compliant, lead-free (#TRMPBF).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G50DBVR and MAX6369KA+T, the LTC2909ITS8-5#TRMPBF uniquely supports dual-rail monitoring with polarity selection and buffered 1V reference - essential for mixed positive/negative supply systems - while maintaining ±1.5% accuracy and 0.5V minimum operating voltage.

Availability

LTC2909ITS8-5#TRMPBF is available at Aetrix Electronics and suitable for industrial automation, automotive electronics, network infrastructure, and embedded computing applications requiring stable component supply and long-term lifecycle support.

Supply support for LTC2909ITS8-5#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 technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC2909ITS8-5#TRMPBF belongs to ADI's precision voltage supervisor product line, engineered for high-accuracy, low-power, multi-rail power monitoring in space-constrained and thermally demanding environments.

FAQ

What is the guaranteed VCC UVLO threshold for LTC2909ITS8-5#TRMPBF?

The LTC2909ITS8-5#TRMPBF has a fixed VCC undervoltage lockout threshold of 4.425V ±1.5%, meaning it guarantees reset assertion for any VCC below 4.35V across the full –40°C to +85°C operating temperature range. This value is factory-trimmed and applies specifically to the "-5" variant, which is optimized for 5V system monitoring.

How does the SEL pin configure input polarity on LTC2909ITS8-5#TRMPBF?

The SEL pin on LTC2909ITS8-5#TRMPBF selects polarity for both ADJ1 and ADJ2 inputs: tied to VCC sets both for positive polarity (UV detection on positive rails), tied to GND sets both for negative polarity (UV detection on negative rails), and left open configures ADJ1 for positive and ADJ2 for negative polarity - enabling simultaneous monitoring of +5V and –12V rails using a single LTC2909ITS8-5#TRMPBF.

Can LTC2909ITS8-5#TRMPBF monitor a negative supply without external op-amps?

Yes. The LTC2909ITS8-5#TRMPBF includes a buffered 1.000V ±15mV REF output that serves as a stable offset reference. When monitoring a negative rail like –12V, connect ADJ2 to a resistor divider between –12V and REF (not GND), allowing the device to detect undervoltage (e.g., –11.4V) or overvoltage (e.g., –12.6V) directly - no external op-amp or level-shifter required.

What is the minimum VCC voltage that ensures reliable RST assertion for LTC2909ITS8-5#TRMPBF?

The LTC2909ITS8-5#TRMPBF guarantees RST output low voltage (V_OL) ≤0.15V at VCC = 3V with 2.5mA sink current, and operation is fully specified down to VCC = 0.5V. At VCC = 0.5V, RST remains asserted with VOL ≤0.30V at 5μA sink - ensuring fail-safe reset behavior during deep brownout conditions where other supervisors may release prematurely.

Does LTC2909ITS8-5#TRMPBF require an external timing capacitor for standard 5V system use?

No. The LTC2909ITS8-5#TRMPBF supports an internal 200ms reset timeout when the TMR pin is tied to GND - eliminating the need for external capacitors in standard 5V applications. This reduces BOM cost and PCB area while providing deterministic reset hold time, unlike capacitor-based solutions subject to tolerance and temperature drift.