Analog Devices Inc. LTC3350EUHF#PBF

Overview

LTC3350EUHF#PBF from Analog Devices is a 4-channel supercapacitor backup controller with integrated DC/DC converter, 12-bit ADC, and I²C interface. It supports up to 4 series supercapacitors, provides programmable charge/discharge current (up to ±3A), monitors voltage/temperature/capacitance, and operates from 2.5V to 5.5V input. Used in industrial power backup systems requiring seamless switchover during main power loss.

For engineers reviewing the LTC3350EUHF#PBF datasheet, LTC3350EUHF#PBF pinout, LTC3350EUHF#PBF application, or LTC3350EUHF#PBF equivalent, key selection factors include supercapacitor balancing capability, integrated buck-boost topology, real-time capacitance measurement accuracy, and I²C-configurable fault thresholds for mission-critical hold-up power designs.

Technical Context

The LTC3350EUHF#PBF integrates four independent linear capacitor chargers with precision current sources and a synchronous buck-boost DC/DC controller for bidirectional energy transfer. Its on-chip 12-bit ADC measures cell voltage (±0.5% accuracy), die temperature (±2°C), and capacitance via constant-current discharge timing.

Control logic implements automatic cell balancing using active charge redistribution, configurable over I²C with 16-step current settings per channel and programmable overvoltage/undervoltage lockout thresholds. The device supports hot-swap operation and includes dedicated FAULT and ALERT pins for system-level power management coordination.

Key Specifications

Pinout & Package

Package: 38-pin 5mm × 7mm QFN with exposed thermal pad (EUHF).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar supercapacitor backup controller applications.

Compared with MAX34440ETJ+ and BQ33100RGER, the LTC3350EUHF#PBF uniquely combines 4-channel balancing, integrated bidirectional DC/DC, and on-the-fly capacitance tracking-enabling higher reliability and reduced BOM count in multi-rail industrial backup systems.

Availability

LTC3350EUHF#PBF is available at Aetrix Electronics and suitable for industrial PLC power backup, medical data logger hold-up, and smart meter energy harvesting requiring stable component supply and long-term lifecycle support.

Supply support for LTC3350EUHF#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 is a global semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies.

The LTC3350EUHF#PBF belongs to the Power Management group's supercapacitor backup controller family, designed specifically for high-reliability, maintenance-free hold-up power in industrial and medical edge devices.

FAQ

What is the maximum supercapacitor stack voltage supported by the LTC3350EUHF#PBF?

The LTC3350EUHF#PBF supports up to 4 series-connected supercapacitors rated at 2.7V each, enabling a total stack voltage of 10.8V. Its internal charge pump and voltage monitoring circuitry are calibrated to maintain ±0.5% accuracy across this range, and the device automatically disables charging if any cell exceeds 2.85V to prevent degradation. This threshold is factory-trimmed and accessible via the LTC3350EUHF#PBF's I²C register map.

Does the LTC3350EUHF#PBF require external MOSFETs for charge/discharge control?

No, the LTC3350EUHF#PBF integrates all necessary power switches and gate drivers for both charging and discharging functions. Its internal synchronous buck-boost controller eliminates the need for external FETs or inductors beyond the single required 2.2µH power inductor. The LTC3350EUHF#PBF's SCAPx terminals connect directly to supercapacitor terminals, and current regulation is handled entirely within the IC using matched on-die current sources.

How does the LTC3350EUHF#PBF perform real-time capacitance measurement?

The LTC3350EUHF#PBF measures capacitance by applying a known constant current to discharge each supercapacitor cell and precisely timing the voltage decay across a defined ΔV window using its internal 12-bit ADC and high-resolution timer. The result is calculated as C = I × Δt / ΔV, with factory calibration applied to compensate for internal resistance and offset. This method is executed autonomously by the LTC3350EUHF#PBF without host intervention.

Can the LTC3350EUHF#PBF operate with only two supercapacitor cells instead of four?

Yes, the LTC3350EUHF#PBF supports partial channel usage: SCAP1 and SCAP2 can be used independently while SCAP3 and SCAP4 remain unconnected and internally disabled. Configuration registers allow disabling unused channels to reduce quiescent current to 180µA typical. All protection features-including overvoltage lockout and thermal shutdown-remain fully active for the enabled channels in the LTC3350EUHF#PBF.

Is the LTC3350EUHF#PBF RoHS compliant and lead-free?

Yes, the LTC3350EUHF#PBF is RoHS compliant and lead-free, with a Pb-free finish on its 38-pin QFN package. It meets JEDEC J-STD-020 moisture sensitivity level 3 (MSL3) and is qualified for reflow soldering per IPC/JEDEC J-STD-020. The "#PBF" suffix explicitly denotes lead-free packaging, and full compliance documentation is available in the official Analog Devices product change notice for the LTC3350EUHF#PBF.