Analog Devices Inc. LTC2922IF-3.3#PBF

Overview

LTC2922IF-3.3#PBF from Analog Devices (formerly Linear Technology) is a precision multi-supply power-tracking and monitoring IC designed for coordinated ramp-up of up to five voltage rails in complex systems. It features five integrated remote sense switches, ±1% 0.5V monitor threshold accuracy, adjustable electronic circuit breaker (50mV trip), and GATE drive output rated to 9.1V (typ) at 3.3V VCC - used in telecom infrastructure and high-reliability plug-in cards requiring strict supply sequencing.

For engineers reviewing the LTC2922IF-3.3#PBF datasheet, LTC2922IF-3.3#PBF pinout, LTC2922IF-3.3#PBF application, or LTC2922IF-3.3#PBF equivalent, key selection considerations include its 20-pin TSSOP package, -40°C to 85°C industrial temperature grade, 3.3V VCC supply compatibility, five-channel remote sensing capability, and programmable TIMER/GATE ramp timing via external RC networks.

Technical Context

The LTC2922IF-3.3#PBF implements a deterministic six-step power-on sequence: (1) VCC UVLO release, (2) simultaneous validation of five input voltages (VCC + V1–V4) against 0.5V/0.7V thresholds, (3) TIMER-initiated delay before GATE ramp, (4) 10µA-controlled GATE voltage ramp to VPUMP (~9.1V), (5) activation of five N-channel remote sense switches with ~8V/ms gate ramp, and (6) second TIMER delay before PG assertion. All steps enforce glitch immunity and tight 1% threshold accuracy.

Its internal architecture includes a charge pump generating VPUMP, dual comparator banks (monitor + overvoltage), latch-based fault management, and independent pull-down circuits for GATE, PG, and remote switches. The SENSE pin enables current-limiting via external resistor (ΔVSENSE ≥50mV for ≥1µs triggers circuit breaker latch), while V1 serves as active-low reset for that latch.

Key Specifications

Pinout & Package

Package: 20-lead plastic TSSOP (F package), 4.4mm × 6.5mm body, 0.65mm pitch, exposed pad for thermal enhancement.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multi-rail supply tracking applications.

Compared with LTC2922CF-3.3#PBF, the LTC2922IF-3.3#PBF offers guaranteed operation down to –40°C - critical for outdoor telecom deployments - while TPS65286RGER trades external FET flexibility and precision tracking for higher integration but sacrifices 0.5V threshold accuracy and remote sense compensation capability.

Availability

LTC2922IF-3.3#PBF is available at Aetrix Electronics and suitable for telecom infrastructure, industrial instrumentation, and desktop motherboard designs requiring stable component supply with long-term lifecycle assurance.

Supply support for LTC2922IF-3.3#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) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC2922IF-3.3#PBF belongs to ADI's Linear Technology legacy power management portfolio, specifically engineered for precision supply tracking, sequencing, and fault protection in multi-rail systems where reliability and accuracy are non-negotiable.

FAQ

What is the primary function of the LTC2922IF-3.3#PBF in a power system?

The LTC2922IF-3.3#PBF functions as a precision multi-supply tracker and monitor, coordinating the ramp-up of up to five voltage rails while enforcing strict tracking alignment, detecting over/under-voltage faults, and providing integrated remote sense switching and electronic circuit breaker protection - all within a single 20-pin TSSOP package.

How does the LTC2922IF-3.3#PBF achieve supply voltage tracking?

The LTC2922IF-3.3#PBF achieves supply voltage tracking by driving the gates of external N-channel MOSFETs via its GATE pin, forcing all connected supplies to rise at the same rate. Its five internal remote sense switches then activate to compensate for IR drops across those FETs, ensuring load-side voltages track within ±5mV - verified by the ±1% 0.5V monitor threshold accuracy.

Can the LTC2922IF-3.3#PBF be used with a 5V VCC supply?

No - the LTC2922IF-3.3#PBF is specifically configured for 3.3V VCC operation (2.97V to 3.63V). Using it with 5V violates absolute maximum ratings and will damage the device. For 5V systems, use LTC2922IF#PBF or LTC2922IF-5#PBF variants explicitly rated for 4.5V–5.5V VCC.

What is the role of the TIMER pin on the LTC2922IF-3.3#PBF?

The TIMER pin on the LTC2922IF-3.3#PBF sets two critical timing intervals in the power-on sequence: first, the delay between successful monitor validation and initiation of GATE ramp; second, the delay between remote sense switch activation and PG assertion. A single external capacitor programs both delays at 600ms/µF.

How is the electronic circuit breaker reset on the LTC2922IF-3.3#PBF?

The electronic circuit breaker on the LTC2922IF-3.3#PBF is reset by pulling the V1 pin below 0.490V for more than 150µs after the overcurrent condition has cleared. Alternatively, an undervoltage lockout event on VCC lasting longer than 10µs also clears the breaker latch - both methods are documented in the LTC2922IF-3.3#PBF datasheet timing diagrams.