LTC4162IUFD-L42 - 35V/3.2A Multi-Cell Li-Ion Charger | Analog Devices
MPN: LTC4162IUFD-L42 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.42 | $7.42 |
| 10 | $6.68 | $66.80 |
| 100 | $5.95 | $595.00 |
| 500 | $5.36 | $2,680.00 |
| 1,000 | $4.79 | $4,790.00 |
LTC4162IUFD-L42 Overview
A switching battery charger (also called a switch-mode battery charger or buck charger IC) is a power management device that converts a higher DC input voltage to a lower, precisely regulated voltage/current suitable for safely charging a rechargeable cell stack. It belongs to the family of power management ICs (PMICs), specifically battery management PMICs, sitting between general DC-DC converters and dedicated battery fuel gauges in the functional hierarchy.
Key features include 4.5V to 35V input voltage range, factory-set 4.2V per-cell charge voltage with ±1% accuracy, programmable charge current up to 3.2A, integrated N-channel MOSFET synchronous PowerPath stage, and I2C/SMBus telemetry reporting input voltage, battery voltage, charge current, die temperature, and system voltage. The synchronous buck topology achieves charging efficiencies above 90 percent, while the 4mm x 5mm QFN-28 package keeps the solution footprint compact.
Typical applications include USB-C Power Delivery (PD) charging for 2-cell to 8-cell Li-ion battery packs in industrial handhelds, medical carts, power tools, e-bikes, portable solar backup systems, and uninterruptible DC supplies. Because it operates directly from 24V industrial rails, the LTC4162IUFD-L42 also suits building automation and telecom backup modules.
When designing with this device, place input/output ceramic capacitors close to the IC pins and keep the high-current loop area minimal to suppress EMI. The exposed pad must be soldered to a sufficient copper pour to keep junction temperature within ratings; an NTC thermistor or the internal die sensor can be used for JEITA-style thermal protection.
Drop-in alternatives for LTC4162IUFD-L42 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with LTC4162IUFD-L42 (same form factor and footprint) — differing in Number of Cells Supported, Operating Temperature Range, Package, RoHS Status, Topology.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LTC4162EUFD-L42
✅ Drop-In✓ In Stock
$8.75 / Unit
View Datasheet →LTC4162IUFD-L42M#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC4162EUFD-L41
✅ Drop-In📋 Reference alternative (not in catalog)
LTC4162EUFD-L40
✅ Drop-In📋 Reference alternative (not in catalog)
LTC4162IUFD-F42
✅ Drop-In📋 Reference alternative (not in catalog)
LTC4162IUFD-L40
✅ Drop-In📋 Reference alternative (not in catalog)
LTC4162IUFD-L42 Specifications
| Function | Synchronous step-down switching battery charger with PowerPath manager |
| Cell Chemistry | Lithium-Ion / Lithium-Polymer |
| Number of Cells Supported | 1 to 8 cells |
| Input Voltage Range | 4.5 V to 35 V |
| Maximum Charge Current | 3.2 A |
| Factory Charge Voltage | 4.2 V per cell |
| Charge Voltage Accuracy | +/-1% (per Analog Devices datasheet) |
| Topology | Synchronous buck (step-down) with integrated N-channel MOSFETs |
| PowerPath Control | Integrated, decouples system load from battery |
| Telemetry Interface | I2C / SMBus |
| Package | 28-pin QFN-EP (UFD), 4 mm x 5 mm x 0.75 mm |
| Mounting Type | Surface Mount |
| Operating Temperature Range | -40 C to +125 C (I-grade) |
| RoHS Status | Compliant |
| MSL Level | 1 (per Analog Devices packaging information) |
LTC4162IUFD-L42 Pin Configuration
| Pin 1 | VIN — Input supply to the switching charger (4.5 V to 35 V) |
| Pin 2 | VIN — Input supply (parallel pin for high-current) |
| Pin 3 | SCL — I2C serial clock input |
| Pin 4 | SDA — I2C serial data input/output |
| Pin 5 | ADR — I2C address select |
| Pin 6 | INT — Interrupt output (open-drain, active low) |
| Pin 7 | CHRG — Charge status output (open-drain) |
| Pin 8 | GND — Analog ground |
| Pin 9 | PROG — Charge current programming resistor |
| Pin 10 | ILIM — Input current limit programming |
| Pin 11 | NTC — Battery thermistor input |
| Pin 12 | BAT — Battery connection sense |
| Pin 13 | BAT — Battery connection (high-current) |
| Pin 14 | SYS — System load output (PowerPath output) |
| Pin 15 | SYS — System load output (parallel pin) |
| Pin 16 | SW1 — Switch node 1 (buck high-side) |
| Pin 17 | SW1 — Switch node 1 (parallel) |
| Pin 18 | SW2 — Switch node 2 (buck low-side) |
| Pin 19 | SW2 — Switch node 2 (parallel) |
| Pin 20 | BST — Bootstrap capacitor for high-side gate drive |
| Pin 21 | VC — Internal LDO bypass |
| Pin 22 | VOUT — Charger output regulation |
| Pin 23 | CLPROG — Current-limit programming |
| Pin 24 | DTHM — Die temperature monitor output |
| Pin 25 | ACPR — AC adapter present indicator |
| Pin 26 | EN — Enable input (active high) |
| Pin 27 | SUSP — Suspend input (low Iq mode) |
| Pin 28 | EP — Exposed pad - thermal pad, must be soldered to ground plane |
Typical Applications
LTC4162IUFD-L42 is suitable for 6 applications: USB-C PD Charging for 2S-4S Li-Ion Power Tools, Industrial Handheld Computer Battery Management, Medical Cart and Portable Diagnostic Equipment, Solar-Powered IoT Gateway with Battery Backup, E-Bike and Light Electric Vehicle Battery Packs, Telecom 24V/48V Battery Backup Module.
USB-C PD Charging for 2S-4S Li-Ion Power Tools
The LTC4162IUFD-L42 fits USB-C PD charging for 2S-4S cordless power tools because its 4.5 V to 35 V input range directly accepts 5 V to 20 V PD source voltages without pre-regulation. The 3.2 A programmable charge current enables fast-charge of high-capacity 18650/21700 packs in under an hour, while integrated PowerPath control lets the tool run from the adapter even with a depleted battery. The 4mm x 5mm QFN-28 footprint occupies less than 100 mm2 of PCB area, leaving room for compact tool handles.
Recommended
Industrial Handheld Computer Battery Management
For industrial handhelds running barcode scanners and RFID readers, the LTC4162IUFD-L42 provides reliable 2S to 4S Li-ion charging with its industrial -40 C to +125 C operating range. The I2C telemetry interface lets the host MCU log charge cycles for predictive maintenance, and the integrated thermal regulation prevents overheating during hot-swap operations. Synchronous buck topology delivers >90% charging efficiency, extending runtime between adapter insertions in warehouse environments.
Recommended
Medical Cart and Portable Diagnostic Equipment
Medical carts and portable ultrasound/diagnostic devices require multi-cell Li-ion battery packs with certified charging safety. The LTC4162IUFD-L42 supports 4S to 6S packs (16.8 V to 25.2 V) with +/-1% factory voltage accuracy, ensuring consistent charge termination that protects cells from overcharge. The exposed-pad QFN-28 package allows direct PCB thermal management without heatsinks, and the I2C die-temperature telemetry enables JEITA-style thermal foldback for patient-safety-critical designs.
Recommended
Solar-Powered IoT Gateway with Battery Backup
The LTC4162IUFD-L42's 35 V input range lets it charge 2S to 4S backup batteries directly from 12 V to 24 V solar panels with MPPT input filters, eliminating a separate buck stage. Integrated PowerPath control instantly switches the gateway load to the battery when solar input drops below threshold, ensuring continuous IoT connectivity. I2C telemetry enables cloud-based state-of-charge reporting, and the synchronous design minimizes quiescent loss for off-grid installations.
Recommended
E-Bike and Light Electric Vehicle Battery Packs
E-bikes and personal mobility devices use 7S to 8S Li-ion packs (29.4 V to 33.6 V full charge). The LTC4162IUFD-L42 charges these packs directly from a 30 V to 35 V nominal charger source, while its 3.2 A current supports packs up to 10 Ah in roughly 3 hours. Industrial temperature rating tolerates outdoor summer/winter exposure, and the 28-pin QFN exposed pad spreads heat evenly across the controller PCB. Synchronous buck topology preserves charger efficiency above 90% at full load.
Recommended
Telecom 24V/48V Battery Backup Module
For telecom backup modules operating from 24 V or 48 V rectified rails, the LTC4162IUFD-L42 charges 6S to 8S Li-ion backup batteries (25.2 V to 33.6 V) directly from the bus. The 35 V maximum input withstands 48 V rail transients per telecom surge standards, while the synchronous buck stage maintains high efficiency at typical telecom float voltages. I2C reporting lets the central office monitor backup state-of-charge over the existing management bus.
Recommended
Recommended Products Summary
Engineering reference data for LTC4162IUFD-L42 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LTC4162EUFD-L42 | LTC4162IUFD-L42M#PBF | LTC4162EUFD-L41 | LTC4162EUFD-L40 |
|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | QFN-28 (UFD) 4x5 mm | QFN-28 (UFD) 4x5 mm - same | QFN-28 (UFD) 4x5 mm - same | QFN-28 (UFD) 4x5 mm - same | QFN-28 (UFD) 4x5 mm - same |
| Input Voltage Range | 4.5 V to 35 V | 4.5 V to 35 V | 4.5 V to 35 V | 4.5 V to 35 V | 4.5 V to 35 V |
| Maximum Charge Current | 3.2 A | 3.2 A | 3.2 A | 3.2 A | 3.2 A |
| Factory Charge Voltage (per cell) | 4.2 V | 4.2 V | 4.2 V | 4.1 V | 4.0 V |
| Temperature Grade | Industrial (-40 C to +125 C) | Extended commercial (0 C to +85 C) | Military plastic flow | Extended commercial (0 C to +85 C) | Extended commercial (0 C to +85 C) |
| PowerPath Control | Yes (integrated) | Yes (integrated) | Yes (integrated) | Yes (integrated) | Yes (integrated) |
| I2C Telemetry | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- Integrated PowerPath eliminates external MOSFET load switch (vs Discrete buck charger with external load-sharing FETs)
- I2C telemetry reduces external fuel-gauge requirement (vs External battery fuel gauge IC (e.g., LTC2943))
- 35 V absolute-max input withstands 24 V industrial surge (vs Lower-input competitors (e.g., 20 V max))
Design Notes
Estimated: at VIN=20 V, VOUT=8.4 V (2S), 2 A charge current, the LTC4162IUFD-L42 dissipates roughly (20-8.4)*2 = 23.2 W. The QFN-28 (UFD) 4x5 mm package requires at least 1 square inch of top-layer copper pour tied to the exposed pad to keep junction rise below 50 C. For continuous 3.2 A charging in enclosed enclosures, add bottom-layer copper and thermal vias to spread heat to the inner planes.
Keep the high-current loop (VIN to SW1/SW2 to SYS/BAT and back to GND) area under 0.5 cm2 to suppress radiated EMI. Place input ceramic capacitors (typically 10 uF X7R) within 3 mm of the VIN pins and the exposed pad. Route the I2C SCL/SDA traces away from the SW node and use a ground guard on both sides to maintain signal integrity for telemetry reads.
Do not omit the bootstrap capacitor on BST - the high-side N-channel MOSFET requires it for gate drive above VIN. The NTC thermistor network must use a 10 kohm B-curve (3950) device referenced to the analog ground; wrong NTC values cause premature charge termination. Finally, verify the I2C address pin ADR is tied to GND or VCC before firmware release - floating ADR can corrupt bus addressing on hot-plug events.
Program the input current limit via ILIM resistor to prevent tripping upstream USB-C or wall-adapter sources. For USB-C PD 5 V/3 A sources, set ILIM to 3 A; for standard 5 V/2.4 A adapters, set ILIM to 2.4 A. This prevents the adapter from collapsing its output during the inrush of a depleted battery, which would otherwise trigger the LTC4162IUFD-L42's ACPR flag and disable charging.
Compliance Information
RoHS and REACH compliant per Analog Devices product page. Not AEC-Q100 qualified - use AEC-Q100 grade ADI parts for automotive. Halogen-free and lead-free per ADI packaging information.
