Analog Devices Inc. LTC2900-1IDD#TRPBF

Overview

LTC2900-1IDD#TRPBF from Analog Devices (acquired Linear Technology) is an open-drain programmable quad supply monitor IC that simultaneously supervises four independent voltage rails - including 5V, 3.3V, 2.5V, 1.8V, 1.5V, and ±adjustable thresholds - with ±1.5% threshold accuracy over temperature, 43µA typical supply current, and adjustable reset timeout via external capacitor. It is used in multivoltage server power systems to ensure reliable power-on reset sequencing before CPU and FPGA initialization.

For engineers reviewing the LTC2900-1IDD#TRPBF datasheet, LTC2900-1IDD#TRPBF pinout, LTC2900-1IDD#TRPBF application, or LTC2900-1IDD#TRPBF equivalent, key selection criteria include guaranteed RST assertion down to VCC = 1V, manual reset input with debounced timing, glitch immunity during brownout, and compatibility with 3mm × 3mm DFN-10 packaging for space-constrained board layouts.

Technical Context

The LTC2900-1IDD#TRPBF implements four independent high-accuracy comparators referenced to a buffered 1.210V internal bandgap, each configurable via a single VPG pin using a 1% resistive divider to select among 16 preset or adjustable voltage combinations. Its architecture guarantees correct RST logic state at VCC ≥ 1V and supports both positive-adjustable (ADJ) and negative-adjustable (–ADJ) monitoring modes for asymmetric rail supervision.

Reset timing is externally programmable via CRT pin capacitance (4.6ms/nF scaling), with minimum delay of ~50µs when left floating. The open-drain RST output features weak internal pull-up to V2 (~6µA typical), enabling flexible level-shifting and external pull-up customization for faster rise times or higher VOH.

Key Specifications

Pinout & Package

Package: 10-lead 3mm × 3mm plastic DFN (exposed pad), RoHS-compliant, θJA = 43°C/W, rated for –40°C to 85°C operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC2901CMS#PBF, LTC2900-1IDD#TRPBF offers smaller DFN-10 packaging and simpler reset-only functionality, while LTC1326CS8#PBF trades quad capability for higher accuracy on three rails - making LTC2900-1IDD#TRPBF the optimal balance of channel count, adjustability, and size for multivoltage embedded systems.

Availability

LTC2900-1IDD#TRPBF is available at Aetrix Electronics and suitable for server power sequencing, industrial PLC I/O modules, telecom line cards, and portable medical instruments requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC2900-1IDD#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, 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 LTC2900 family was originally developed by Linear Technology (acquired by ADI in 2017) to address demand for highly configurable, low-power quad supply monitors in dense multivoltage systems - particularly servers, telecom infrastructure, and precision instrumentation.

FAQ

What is the minimum VCC voltage required for LTC2900-1IDD#TRPBF to assert a valid RST output?

The LTC2900-1IDD#TRPBF guarantees correct RST logic state for VCC ≥ 1V. This means the device will hold RST low during brownout conditions until VCC drops below 1V, ensuring fail-safe reset behavior even under severe undervoltage. Below 1V, internal circuitry ceases operation and RST becomes undefined - design must ensure downstream logic interprets this as invalid or masked.

How does the LTC2900-1IDD#TRPBF support negative voltage monitoring?

The LTC2900-1IDD#TRPBF supports negative voltage monitoring in –ADJ mode on V4 input, where an external resistive divider connects between the negative rail and VREF (1.210V). VREF acts as a level-shift reference, enabling trip point calculation as VTRIP = –(VREF × R3/R4). For example, –5.2V monitoring uses R3 = 487kΩ and R4 = 121kΩ per datasheet Table 3 - confirmed in LTC2900-1IDD#TRPBF typical application TA05.

Can the LTC2900-1IDD#TRPBF monitor four different voltage rails simultaneously, and what are the supported threshold options?

Yes, the LTC2900-1IDD#TRPBF simultaneously monitors four independent rails (V1–V4) with 16 preconfigured combinations selectable via VPG pin. Supported thresholds include fixed points (5V, 3.3V, 3V, 2.5V, 1.8V, 1.5V) and adjustable modes (ADJ for positive rails, –ADJ for negative rails). Each combination specifies exact thresholds per input - e.g., Mode 6 (R1=59.0kΩ/R2=40.2kΩ) configures V1=5V, V2=3.3V, V3=2.5V, V4=1.8V - all verified in datasheet Table 1.

What is the function of the CRT pin on the LTC2900-1IDD#TRPBF, and how is reset timeout calculated?

The CRT pin on the LTC2900-1IDD#TRPBF sets reset timeout by connecting an external capacitor to GND. Timeout scales linearly at 4.6ms/nF - e.g., 47nF yields tRST ≈ 216ms. Leaving CRT unconnected gives ~50µs minimum. The relationship is defined as CRT (F) = tRST (s) × 217×10⁻⁹, validated by Figure 2900 G16 and typical application TA01 - no external resistor or IC is needed for timing.

Does the LTC2900-1IDD#TRPBF have built-in ESD protection, and what is the recommended layout practice for the PBR pin?

The LTC2900-1IDD#TRPBF includes internal ESD protection on all pins per standard HBM specifications, but the PBR pin benefits from an optional 1kΩ series resistor (RL1 in TA05) to extend ESD tolerance during manual button actuation. Layout best practice is to route PBR directly to a normally-open momentary switch with short traces, avoid stubs or vias near the pin, and maintain clean ground return - confirmed in typical application TA05 schematic and layout notes.