Analog Devices Inc. LTC2900-1CDD#PBF

Overview

LTC2900-1CDD#PBF from Analog Devices (formerly Linear Technology) is a programmable quad supply monitor IC with open-drain reset output, simultaneously supervising up to four independent 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 is used in multivoltage embedded systems requiring reliable power-on reset and brownout detection.

For engineers reviewing the LTC2900-1CDD#PBF datasheet, LTC2900-1CDD#PBF pinout, LTC2900-1CDD#PBF application, or LTC2900-1CDD#PBF equivalent, key selection criteria include its 10-pin DFN (3mm × 3mm) package, VCC operation down to 1V, manual reset input with debounced timing, glitch-immune comparators, and support for both positive and negative adjustable thresholds via external resistor dividers.

Technical Context

The LTC2900-1CDD#PBF implements four independent high-accuracy voltage comparators referenced to a buffered 1.210V internal bandgap, with threshold selection determined by a single VPG pin driven by a precision resistive divider. Its architecture guarantees RST assertion during power-up, power-down, and brownout on any monitored rail - with no false triggers due to built-in comparator hysteresis and >150µs glitch immunity.

Reset timing is controlled by an external CRT capacitor (4.6ms/nF scaling), enabling precise delay tuning from ~50µs to seconds; the open-drain RST output pulls low when any input falls below its programmed threshold and remains asserted for the full timeout after all inputs recover. The device draws only 43µA quiescent current and operates with VCC as low as 1V, making it suitable for battery-backed and ultra-low-power applications.

Key Specifications

Pinout & Package

Package: 10-lead plastic DFN (3mm × 3mm), exposed pad, RoHS-compliant, thermal resistance 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 LTC2902CMS#PBF and LTC2901CMS#PBF, the LTC2900-1CDD#PBF delivers essential quad monitoring in the smallest footprint (3mm × 3mm DFN), supports negative rail supervision, and achieves lowest quiescent current - making it optimal for space-constrained, battery-sensitive, or dual-polarity applications without advanced features.

Availability

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

Supply support for LTC2900-1CDD#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 acquired Linear Technology in 2017 and maintains its high-precision analog IC portfolio, emphasizing performance, reliability, and application-specific integration for industrial, automotive, and communications markets.

The LTC2900 family was designed specifically for multivoltage system supervision - delivering accurate, low-power, programmable reset generation in compact packages for computing, telecom, and embedded control applications.

FAQ

What is the function of the CRT pin on the LTC2900-1CDD#PBF?

The CRT pin on the LTC2900-1CDD#PBF sets the reset timeout duration by connecting an external capacitor to ground. With a scaling factor of 4.6ms/nF, a 47nF capacitor yields ~216ms delay. Leaving CRT unconnected results in a minimum ~50µs timeout. This capacitor directly controls the internal timer that holds RST low after all monitored voltages recover.

Does the LTC2900-1CDD#PBF support monitoring of negative voltage rails?

Yes, the LTC2900-1CDD#PBF supports negative rail monitoring in –ADJ mode on the V4 input. In this configuration, an external resistor divider connects between the negative supply and VREF (1.210V), with the tap applied to V4. The trip point is calculated as VTRIP = –(VREF × R3/R4), enabling accurate supervision of rails like –5V or –12V without external level-shifting components.

What is the difference between LTC2900-1CDD#PBF and LTC2900-2CDD#PBF?

The LTC2900-1CDD#PBF features an open-drain RST output with weak internal pull-up to V2, while the LTC2900-2CDD#PBF uses a push-pull (active pull-up) RST output referenced to V2. This makes LTC2900-2CDD#PBF better suited for driving heavy capacitive loads or CMOS inputs directly, whereas LTC2900-1CDD#PBF allows flexible external pull-up voltage selection and higher VOH levels.

How is threshold programming implemented on the LTC2900-1CDD#PBF?

Threshold programming on the LTC2900-1CDD#PBF is performed via the VPG pin, which accepts a voltage divider tap between VREF (1.210V) and GND. Sixteen combinations (e.g., 5V/3.3V/2.5V/1.8V or ADJ/–ADJ variants) are selected by setting VPG to specific ratios of VREF (±0.01). The part samples VPG during a ~150µs window after VCC rises above 2.4V, then locks the configuration.

What is the minimum supply voltage required for valid RST output on the LTC2900-1CDD#PBF?

The LTC2900-1CDD#PBF guarantees correct RST logic state (low during fault, high otherwise) for VCC ≥ 1V. This is critical for brownout resilience: even as the greater of V1 or V2 drops toward 1V, the device continues asserting reset until full power loss, preventing erratic MCU behavior during failing supply conditions.