Analog Devices Inc. LTC2909CTS8-5#TRMPBF

Overview

LTC2909CTS8-5#TRMPBF from Analog Devices (formerly Linear Technology) is a precision dual adjustable-input undervoltage/overvoltage monitor with integrated 5V UVLO, buffered 1V reference, and open-drain reset output. It features ±1.5% threshold accuracy over temperature, 50μA quiescent current, and pin-selectable input polarity for monitoring positive or negative supplies - used in core voltage supervision of 5V systems in network servers and industrial controllers.

For engineers reviewing the LTC2909CTS8-5#TRMPBF datasheet, LTC2909CTS8-5#TRMPBF pinout, LTC2909CTS8-5#TRMPBF application, or LTC2909CTS8-5#TRMPBF equivalent, key selection considerations include VCC UVLO threshold (4.350–4.500V), ADJ input trip point (0.4925–0.5075V), internal 200ms timeout capability, and TSOT-23-8 package compatibility with space-constrained PCB layouts.

Technical Context

The LTC2909CTS8-5#TRMPBF implements two independent 0.5V nominal comparator inputs with polarity controlled by the three-state SEL pin (VCC/Open/GND), enabling configurable UV/OV detection on positive or negative rails. Its third fixed-threshold monitor operates on VCC with 4.350V minimum UVLO trip and 0.3–2.0% hysteresis.

Reset assertion uses glitch-filtered comparator outputs feeding a programmable timeout circuit - selectable via TMR pin as internal 200ms, external capacitor (9ms/nF), or disabled (comparator mode). The buffered 1.000V REF output supports offset-based negative-supply monitoring and drives up to 1mA with ±15nA ADJ input bias.

Key Specifications

Pinout & Package

Package: 8-lead TSOT-23 (3mm × 1.75mm), RoHS-compliant, exposed pad not present in TSOT-23 variant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-rail voltage monitoring applications.

Compared with MAX6816EUT+T and TPS3808G12DBVR, the LTC2909CTS8-5#TRMPBF uniquely delivers dual-rail monitoring with polarity flexibility, integrated reference, and sub-1V brownout detection - making it irreplaceable for multi-rail systems requiring coordinated reset timing and negative supply supervision.

Availability

LTC2909CTS8-5#TRMPBF is available at Aetrix Electronics and suitable for network server power management, industrial PLC supervision, and automotive infotainment power sequencing requiring stable component supply and long-term lifecycle support.

Supply support for LTC2909CTS8-5#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. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors.

The LTC2909 product line delivers precision, low-power, multi-rail voltage supervisors optimized for complex power architectures in computing, industrial, and automotive applications - emphasizing accuracy, configurability, and robustness under brownout conditions.

FAQ

What is the guaranteed minimum VCC UVLO threshold for LTC2909CTS8-5#TRMPBF?

The guaranteed minimum VCC UVLO threshold for LTC2909CTS8-5#TRMPBF is 4.350V across the full operating temperature range (–40°C to 85°C), per the Electrical Characteristics table. This value corresponds to the 5V-specific version and ensures reliable reset assertion before 5V system logic becomes unstable. The typical threshold is 4.425V, with maximum 4.500V. These values are specified with ±1.5% accuracy relative to the nominal 5V supply.

Can LTC2909CTS8-5#TRMPBF monitor a negative supply voltage?

Yes, LTC2909CTS8-5#TRMPBF can monitor negative supplies using its adjustable ADJ inputs with polarity selection via the SEL pin. When SEL = GND, both ADJ1 and ADJ2 are configured for negative polarity, meaning they assert reset if the input voltage rises above the 0.5V threshold - enabling detection of negative-rail overvoltage (e.g., –4.3V on a –5V rail). The buffered 1V REF output serves as the reference point for resistor-divider networks tied to negative rails.

What is the function of the TMR pin on LTC2909CTS8-5#TRMPBF?

The TMR pin on LTC2909CTS8-5#TRMPBF controls reset timeout behavior: tying it to GND enables the internal 200ms timeout; connecting it to VCC places the device in comparator mode (no timeout, direct output); and connecting an external capacitor to GND sets a programmable timeout (9ms/nF). The pin draws only ±2.1μA, allowing direct MCU GPIO control. In comparator mode, one-sided hysteresis (≈0.7%) is added to prevent oscillation near trip points.

Does LTC2909CTS8-5#TRMPBF require external components for basic operation?

LTC2909CTS8-5#TRMPBF requires minimal external components for basic operation: a 0.1μF bypass capacitor on VCC and an external pull-up resistor on RST. No resistors are needed for polarity selection (SEL pin connects to VCC, GND, or floats), and the internal 200ms timeout eliminates need for a timing capacitor. Adjustable trip points require resistor dividers on ADJ1/ADJ2, but these are application-specific - not mandatory for functional reset assertion.

What package type is used for LTC2909CTS8-5#TRMPBF?

LTC2909CTS8-5#TRMPBF uses the 8-lead TSOT-23 package (3mm × 1.75mm footprint), distinct from the DFN variant (DDB). This package has no exposed thermal pad and is optimized for high-density layouts. Pin numbering follows standard TSOT-23 orientation: ADJ1 (1), ADJ2 (2), REF (3), GND (4), RST (5), VCC (6), TMR (7), SEL (8). The "TS8" in the part number explicitly denotes this TSOT-23 packaging.