Analog Devices Inc. LTC2900-1IDD#PBF

Overview

LTC2900-1IDD#PBF from Analog Devices (acquired Linear Technology) is a programmable quad supply monitor IC with open-drain RST output, simultaneously monitoring up to four voltage rails (e.g., 5V, 3.3V, 2.5V, 1.8V), ±1.5% threshold accuracy over temperature, 43µA typical supply current, and adjustable reset timeout via external capacitor. It serves as a system-level power supervisor in multivoltage embedded systems requiring reliable brownout and power-up reset assertion.

For engineers reviewing the LTC2900-1IDD#PBF datasheet, LTC2900-1IDD#PBF pinout, LTC2900-1IDD#PBF application, or LTC2900-1IDD#PBF equivalent, key selection criteria include its 10-lead 3mm × 3mm DFN package, VCC operation down to 1V, manual reset (PBR) support, guaranteed glitch immunity, and compatibility with both positive adjustable (ADJ) and negative adjustable (–ADJ) input configurations.

Technical Context

The LTC2900-1IDD#PBF implements four independent high-accuracy comparators referenced to a buffered 1.210V internal bandgap, with thresholds selected via a resistor divider on VPG to choose among 16 preset combinations. Its architecture guarantees correct RST state for VCC ≥ 1V and supports manual reset propagation with programmable delay.

Reset timing is set by an external capacitor on CRT (4.6ms/nF scaling), while V1/V2 define internal VCC - the greater of the two powers the circuit and serves as the pull-up reference for the open-drain RST output. Input current on V3/V4 drops to <15nA in ADJ/–ADJ modes, enabling high-impedance sensing of precision-adjusted or negative rails.

Key Specifications

Pinout & Package

Package: 10-lead 3mm × 3mm plastic DFN (exposed pad), RoHS-compliant, θJA = 43°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC2900-1IDD#PBF, LTC2902CMS#PBF adds margining and tolerance control but requires PCB redesign, while LTC2901CMS#PBF integrates watchdog timing but omits negative rail monitoring - making LTC2900-1IDD#PBF optimal for cost-sensitive, space-constrained designs needing flexible quad-rail and bipolar sensing.

Availability

LTC2900-1IDD#PBF is available at Aetrix Electronics and suitable for desktop computers, telecom infrastructure, and network servers requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for LTC2900-1IDD#PBF 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) acquired Linear Technology in 2017 and continues its legacy of high-performance analog, power management, and supervisory ICs for demanding industrial and communications applications.

The LTC2900 family was designed specifically for multivoltage system supervision - delivering accurate, low-power, and highly configurable quad-rail monitoring in compact DFN and MSOP packages for space-constrained embedded platforms.

FAQ

What is the function of the VPG pin on the LTC2900-1IDD#PBF?

The VPG pin on the LTC2900-1IDD#PBF selects one of 16 predefined voltage threshold combinations via a resistor divider connected between VREF and GND. During the ~150µs power-up programming window, the device samples VPG voltage and configures V1–V4 comparators accordingly - enabling flexible rail monitoring without firmware or external configuration storage. The LTC2900-1IDD#PBF datasheet specifies exact resistor values for each combination in Table 1.

Does the LTC2900-1IDD#PBF support monitoring negative supply voltages?

Yes, the LTC2900-1IDD#PBF supports negative rail monitoring in –ADJ mode on the V4 input. In this mode, VREF (1.210V) serves as a level-shift reference: an external resistor divider between the negative supply and VREF connects to V4's inverting input, allowing precise trip-point setting (e.g., –4.64V). The LTC2900-1IDD#PBF specification confirms VRTAN = ±18mV offset accuracy in –ADJ mode, validated across –40°C to 85°C.

What is the minimum VCC required for valid RST output on the LTC2900-1IDD#PBF?

The LTC2900-1IDD#PBF guarantees correct RST logic state (active-low assertion or high-impedance release) for VCC ≥ 1V. This is explicitly specified in the Absolute Maximum Ratings table and confirmed in the "Power-Up" section: RST asserts low as soon as V1 or V2 reaches 1V, and remains valid through brownout down to that threshold. The LTC2900-1IDD#PBF's internal bandgap and comparator circuitry are designed to operate reliably at this low VCC.

How is reset timeout adjusted on the LTC2900-1IDD#PBF?

Reset timeout on the LTC2900-1IDD#PBF is set by an external capacitor (CRT) connected between the CRT pin and GND. The relationship is linear: tRST ≈ 4.6ms per nanofarad (e.g., 47nF yields ~216ms). Leaving CRT unconnected gives a minimum ~50µs delay. The LTC2900-1IDD#PBF datasheet specifies CRT tolerance and leakage sensitivity - ceramic capacitors are recommended to maintain timing accuracy within ±10%.

What distinguishes the LTC2900-1IDD#PBF from the LTC2900-2IDD#PBF?

The LTC2900-1IDD#PBF features an open-drain RST output with weak internal pull-up to V2, whereas the LTC2900-2IDD#PBF uses a push-pull (active pull-up) RST output. This affects external interface requirements: LTC2900-1IDD#PBF may need an external pull-up for faster rise times or VOH > V2, while LTC2900-2IDD#PBF drives high actively to V2. Both share identical monitoring, programming, and timing specifications - the RST architecture is the sole functional difference.