Analog Devices Inc. LTC4015IUHF#TRPBF

Overview

LTC4015IUHF#TRPBF from Analog Devices (formerly Linear Technology) is a multichemistry synchronous buck battery charger controller with integrated digital telemetry, supporting Li-Ion/Polymer, LiFePO₄, and lead-acid batteries. It delivers up to 8A charge current, operates from 4.5V–35V input, supports up to 35V battery voltage, and features I²C programmability, Coulomb counting, and MPPT. It is used in ruggedized portable computing and industrial handhelds requiring precise, telemetry-enabled charging.

For engineers reviewing the LTC4015IUHF#TRPBF datasheet, LTC4015IUHF#TRPBF pinout, LTC4015IUHF#TRPBF application, or LTC4015IUHF#TRPBF equivalent, key selection criteria include multichemistry algorithm selection via CHEM0/CHEM1 pins, ±1.25% regulated charge voltage tolerance, 475kHz–1MHz programmable switching frequency, and real-time monitoring of VBAT, IBAT, VIN, IIN, and die temperature via integrated 14-bit ADC.

Technical Context

The LTC4015IUHF#TRPBF implements a synchronous buck topology with dual ideal diode controllers (INFET/OUTFET) enabling PowerPath™ operation-prioritizing system load over battery charging and supporting instant-on with discharged batteries. Its digital telemetry subsystem continuously samples eight analog channels using a shared 14-bit ADC with configurable prescalers and coulomb counter resolution down to 0.017mV·hr.

Charging algorithms are selected by hardwired CHEM0/CHEM1 pins (9 combinations), defining termination thresholds, recharge voltages, precharge behavior, and temperature compensation. The device supports both pin-strapped and I²C-adjusted charge voltage (e.g., 4.2V/cell Li-Ion ±1.25%), input current limiting (±2% tolerance), and safety timers (4hr default CV termination).

Key Specifications

Pinout & Package

Package: 38-lead 5mm × 7mm QFN with exposed thermal pad (Pin 39 = GND). RoHS-compliant, lead-free finish, rated for –40°C to +125°C junction temperature (θ_JA = 34°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multichemistry battery charger controller applications.

Compared with BQ24650RGER and MAX17577ATP+T, the LTC4015IUHF#TRPBF uniquely integrates multichemistry algorithm selection, real-time telemetry, Coulomb counting, MPPT, and PowerPath™ ideal diode control in a single 38-pin QFN-reducing BOM count and enabling predictive battery health management in mission-critical portable systems.

Availability

LTC4015IUHF#TRPBF is available at Aetrix Electronics and suitable for portable medical instruments, ruggedized notebook/tablet computers, and industrial handhelds requiring stable component supply, long-term lifecycle support, and guaranteed performance across –40°C to +125°C.

Supply support for LTC4015IUHF#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. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC4015IUHF#TRPBF belongs to Linear's Power Management product line, designed specifically for high-accuracy, telemetry-rich battery charging in demanding portable and ruggedized applications where reliability, multichemistry support, and system-level power intelligence are essential.

FAQ

What battery chemistries does the LTC4015IUHF#TRPBF support?

The LTC4015IUHF#TRPBF supports Li-Ion/Polymer, LiFePO₄, and lead-acid batteries. Chemistry selection is made via hardwired CHEM0/CHEM1 pins (nine combinations), each activating a dedicated algorithm with appropriate charge voltage, termination, precharge, and temperature compensation settings. For example, [HH] configures 4.2V/cell Li-Ion with 97.5% recharge threshold, while [ZZ] selects fixed 2.2V/cell lead-acid absorption voltage. The LTC4015IUHF#TRPBF does not support NiCd or NiMH chemistries.

How does the LTC4015IUHF#TRPBF implement PowerPath™ functionality?

The LTC4015IUHF#TRPBF implements PowerPath™ using two independent ideal diode controllers: INFET manages input-to-system path, and OUTFET controls battery-to-system path. Both feature 50mV forward turn-on and 30mV reverse blocking, enabling seamless switchover with no system voltage droop. During charging, input current is dynamically prioritized to sustain system load first; only excess current charges the battery. This ensures instant-on operation even with a fully discharged battery. The LTC4015IUHF#TRPBF achieves this without external MOSFET drivers or discrete diodes.

What is the resolution and accuracy of the Coulomb counter in the LTC4015IUHF#TRPBF?

The LTC4015IUHF#TRPBF Coulomb counter has a default resolution of 0.017 mV·hr (with prescaler M=512) and total charge error of ±2.5% for |VSENSE| between 10mV and 50mV. Accuracy degrades to <±1.0% at 1mV sense voltage. The counter integrates VCSP–CSN differential voltage across RSNSB, supporting bidirectional current measurement. Calibration is performed automatically at power-up, and values are accessible via I²C register 0x20–0x23. The LTC4015IUHF#TRPBF Coulomb counter operates independently of telemetry activity and remains functional in ship mode (5µA quiescent).

Can the LTC4015IUHF#TRPBF operate without an I²C host controller?

Yes, the LTC4015IUHF#TRPBF operates fully autonomously without I²C. All core functions-including chemistry selection, charge voltage, current limits, and termination-are configured via hardware pins (CHEM0/CHEM1, CELLS0–2, RT, UVCLFB). I²C is optional and used only for runtime adjustments, telemetry readback, alert configuration, and coulomb counter control. Default pin-strapped behavior is defined in the datasheet: e.g., CHEM0=CHEM1=INTVCC selects 4.2V/cell Li-Ion. The LTC4015IUHF#TRPBF retains full charging capability and safety protections even with SDA/SCL unconnected.

What thermal protection features does the LTC4015IUHF#TRPBF include?

The LTC4015IUHF#TRPBF includes junction temperature monitoring with overtemperature shutdown at ~150°C (typical), plus telemetry reporting of die temperature via the 14-bit ADC. It also supports NTC-based battery temperature sensing on the NTC/NTCBIAS pins with ±3.5% ratio accuracy, enabling charge current and voltage derating per JEITA guidelines. Input undervoltage lockout (VIN_DUVLO = 140–250mV hysteresis) and INTVCC undervoltage lockouts (charger: 4.2–4.4V; telemetry: 2.75–2.95V) provide additional thermal failure mitigation by disabling operation before thermal runaway. These protections are active regardless of I²C connection. The LTC4015IUHF#TRPBF thermal design assumes θ_JA = 34°C/W with proper PCB copper pour on Pin 39 (exposed pad).