My Inquiry
My Account
Analog Devices Inc. LTC4085EDE-4#PBF
- Part No.:
- LTC4085EDE-4#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- Battery Chargers
- Package:
- 14-WFDFN Exposed Pad
- Datasheet:
-
LTC4085EDE-4#PBF.pdf
- Description:
- IC BATT CHG LI-ION 1CELL 14DFN
- Quantity:
- Payment:
- Shipping:
Inventory:254
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC4085EDE-4#PBF from Analog Devices (formerly Linear Technology) is a USB power manager and linear Li-ion battery charger with integrated ideal diode control, designed for portable USB-powered devices requiring seamless source arbitration between USB, wall adapter, and battery. It delivers 3.95V float voltage, supports up to 1.2A programmable charge current, enforces selectable 100% or 20% input current limits (e.g., 500mA/100mA), and operates in –40°C to +85°C ambient. It enables load-dependent charging compliance in USB-constrained systems.
For engineers reviewing the LTC4085EDE-4#PBF datasheet, LTC4085EDE-4#PBF pinout, LTC4085EDE-4#PBF application, or LTC4085EDE-4#PBF equivalent, key selection considerations include its 3.95V reduced float voltage for extended battery life at high temperature, internal 215mΩ ideal diode path, NTC thermistor interface for thermal safety, and dual-mode input current limiting controlled by HPWR pin state.
Technical Context
The LTC4085EDE-4#PBF implements a PowerPath™ architecture that dynamically arbitrates between IN (USB/wall), BAT (Li-ion), and OUT (system load) using analog current-mode control loops. Its constant-current/constant-voltage (CC/CV) charger integrates thermal feedback and automatic recharge based on VFLOAT – 95mV threshold, while the ideal diode circuit maintains VOUT within ~55mV of VBAT under 600mA load.
Unlike standard chargers, it features load-dependent charge current reduction: battery current is automatically scaled so IIN = ILOAD + IBAT never exceeds the CLPROG-programmed limit (e.g., 500mA), with no microcontroller required. The absence of undervoltage current limit (vs. LTC4085-3) means charge current remains stable down to VOUT ≥ 2.75V, per its -4 variant specification.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Float Voltage | 3.95V ±35mV - Optimized for long-term capacity retention and reduced swelling in prismatic/polymer cells at >60°C operation. |
| Max Charge Current | 1.2A - Programmable via PROG pin resistor; supports fast charging of single-cell Li-ion with thermal regulation. |
| Input Current Limit | Selectable 100% or 20% of CLPROG-set value (e.g., 500mA/100mA) - Enables strict USB 2.0 compliance and low-power suspend mode. |
| Ideal Diode RON | 215mΩ - Internal PFET path from BAT to OUT ensures minimal voltage drop during battery backup, eliminating need for external Schottky. |
| NTC Interface | VNTC = 4.4–4.85V bias; hot threshold = 32.6% × VNTC - Supports precision battery temperature monitoring with external thermistor. |
| Operating Temp | –40°C to +85°C - Fully specified across industrial temperature range; junction max 110°C with θJA = 43°C/W. |
| Package | 14-lead (4mm × 3mm) DFN with exposed pad - Thermally enhanced for linear regulator power dissipation; RoHS-compliant lead-free finish. |
Pinout & Package
Package: 14-lead plastic DFN (4mm × 3mm × 0.75mm), exposed pad connected to GND for thermal and electrical integrity.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| IN (Pin 1) | USB/wall input supply | Accepts 4.35–5.5V; current-limited by CLPROG/HPWR; powers OUT and charges BAT when enabled. |
| OUT (Pin 2) | System power output | Delivers regulated power to load from IN or BAT; requires ≥4.7μF bypass capacitor; supports wall adapter input when VIN = 0. |
| CLPROG (Pin 3) | Input current limit programming | Resistor to GND sets IIN(MAX); also provides real-time IIN monitor voltage (VCLPROG = IIN × RCLPROG/1000). |
| HPWR (Pin 4) | High-power mode select | Logic input: >1.2V → 100% IIN limit; <0.4V → 20% limit; internal 2μA pull-down ensures default low-power startup. |
| SUSP (Pin 5) | USB suspend control | Pull >1.2V to reduce IIN to ≤100μA; preserves battery charging and BAT→OUT ideal diode function. |
| TIMER (Pin 6) | Charge timer capacitor | Capacitor to GND sets full-charge timeout; shorting to GND disables charging entirely. |
| WALL (Pin 7) | Wall adapter detection input | Detects >4.25V to disconnect IN→OUT path and assert ACPR low; enables priority wall adapter operation. |
| NTC (Pin 8) | Thermistor sensing input | Connects to NTC thermistor; monitors battery temperature; charging pauses if outside safe range (hot/cold fault). |
| VNTC (Pin 9) | NTC bias reference | Provides 4.4–4.85V precision bias for NTC network; enables accurate temperature threshold detection. |
| ACPR (Pin 10) | Wall adapter present indicator | Open-drain active-low output; asserts low when WALL >4.25V; disabled if all supplies are below UVLO. |
| CHRG (Pin 11) | Charge status indicator | Open-drain output pulled low during charging; high-impedance when charge complete, timer expired, or supply removed. |
| PROG (Pin 12) | Battery charge current programming | Resistor to GND sets IBAT = 50,000V/RPROG; supports up to 1.2A with 100kΩ resistor. |
| GATE (Pin 13) | External PFET gate driver | Drives optional external P-channel MOSFET to reduce ideal diode impedance; leave floating if unused. |
| BAT (Pin 14) | Battery connection | Connects to single-cell Li-ion anode; used as source during charging and sink during discharge; internal divider sets 3.95V float. |
| GND (Pin 15) | Power and signal ground | Exposed pad must be soldered to PCB ground plane for thermal performance and electrical reference. |
Key Features
| Feature | Design Value |
|---|---|
| 3.95V float voltage | Extends Li-ion cycle life >2× at 60°C vs. 4.2V, reduces polymer cell swelling, prevents cylindrical cell CID activation. |
| Load-dependent charge current | Automatically scales IBAT so IIN = ILOAD + IBAT never exceeds programmed CLPROG limit-no firmware needed. |
| Integrated 215mΩ ideal diode | Eliminates reverse leakage and forward drop of Schottky diodes; enables seamless transition from USB to battery backup. |
| Programmable input current limit | Two-ratio (100%/20%) selection via HPWR pin allows one hardware design to support both USB host and dedicated wall adapter modes. |
| NTC thermistor interface | Hardware-based thermal management with cold/hot fault thresholds; no ADC or software polling required. |
Applications
| USB-Powered Portable Medical Devices | Industrial Handheld Scanners |
|---|---|
Use Scenario: Battery-backed barcode scanner operating in warehouses with intermittent USB charging and frequent wall adapter use. IC Role / Device Role / Timing Role: PowerPath controller managing concurrent USB charging, wall adapter priority, and battery backup with zero switchover delay. Use Value: Maintains uninterrupted operation during USB disconnection; 3.95V float voltage preserves battery capacity over 3+ years of daily thermal cycling. | Use Scenario: Ruggedized handheld data collector used outdoors where ambient temperatures exceed 60°C. IC Role / Device Role / Timing Role: Li-ion charger with thermal cutoff and reduced float voltage to prevent capacity loss and mechanical swelling in sealed enclosures. Use Value: Extends usable battery life by 40% after 500 cycles at 70°C vs. standard 4.2V chargers; eliminates field failures due to swollen cells. |
| USB-C Powered IoT Sensors | Emergency Lighting Control Units |
Use Scenario: Low-power environmental sensor node drawing <100mA from USB-C port while charging a 1000mAh Li-ion cell. IC Role / Device Role / Timing Role: USB current limiter enforcing 100mA compliance in suspend mode while maintaining autonomous battery charging. Use Value: Meets USB-IF power budget requirements without sacrificing runtime; SUSP pin enables firmware-controlled low-power states. | Use Scenario: Backup lighting system requiring fail-safe transition from AC adapter to battery during grid outage. IC Role / Device Role / Timing Role: Ideal diode controller ensuring <10μs switchover from wall adapter to battery with no output droop. Use Value: 215mΩ internal diode and 4.7μF OUT capacitor eliminate need for bulk capacitance; sustains 500mA load during brownout. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar USB power management and Li-ion charging applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BQ24075RGTR | 4.2V float voltage; no NTC interface; fixed 500mA input limit; no ideal diode control | Lacks thermal safety and seamless source arbitration; requires external PFET for battery backup | Choose for cost-sensitive designs where 3.95V float and integrated diode are not required. |
| MAX1555ESA+ | 4.2V float; 100mA/500mA fixed USB limits; no programmable charge current; no WALL/ACPR pins | No wall adapter priority logic or external diode gate drive; limited to basic USB charging | Choose only for legacy USB-only applications without wall adapter support or thermal monitoring. |
Compared with BQ24075RGTR and MAX1555ESA+, the LTC4085EDE-4#PBF uniquely combines 3.95V float voltage for high-temperature reliability, hardware-based ideal diode control, and dual-input (USB/wall) arbitration-all in a thermally optimized DFN package-making it optimal for ruggedized portable electronics demanding long service life.
Availability
LTC4085EDE-4#PBF is available at Aetrix Electronics and suitable for USB-powered medical wearables, industrial handheld scanners, emergency lighting systems, and rugged IoT sensors requiring stable component supply across extended temperature ranges and long product lifecycles.
Supply support for LTC4085EDE-4#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 semiconductors, acquired Linear Technology in 2017 to strengthen its power management portfolio.
The LTC4085EDE-4#PBF belongs to ADI's PowerPath™ family of battery charging and power arbitration ICs, engineered specifically for portable USB devices needing robust thermal management, seamless source handoff, and extended battery longevity in harsh environments.
FAQ
What is the primary function of the LTC4085EDE-4#PBF in a USB-powered system?
The LTC4085EDE-4#PBF serves as a fully integrated USB power manager and Li-ion charger that arbitrates between USB input, wall adapter input, and battery supply to deliver regulated power to the system load. It enforces USB current compliance, manages battery charging with 3.95V float voltage, and provides seamless backup via its internal ideal diode-ensuring continuous operation without firmware intervention. The LTC4085EDE-4#PBF handles all power-path decisions in analog hardware.
How does the LTC4085EDE-4#PBF differ from the LTC4085-3 variant?
The LTC4085EDE-4#PBF omits the undervoltage current limit feature present in the LTC4085-3. This means the LTC4085EDE-4#PBF maintains full programmed charge current down to VOUT ≥ 2.75V, whereas the LTC4085-3 reduces charge current when VOUT falls below ~4.45V. Both share identical 3.95V float voltage, NTC interface, and pinout-making the LTC4085EDE-4#PBF preferable for systems where stable charging under low-output conditions is critical.
Can the LTC4085EDE-4#PBF support wall adapter input directly on the OUT pin?
Yes-the LTC4085EDE-4#PBF supports wall adapter input applied to the OUT pin (load side) when IN is unpowered. Its WALL comparator detects >4.25V on Pin 7, disabling the IN→OUT path and enabling battery charging from the wall adapter via the OUT→BAT path. This configuration avoids reverse current into USB and allows simultaneous load powering and battery charging-functionality confirmed in the LTC4085EDE-4#PBF datasheet Figure 1 and Table 1.
What thermal protection mechanisms are built into the LTC4085EDE-4#PBF?
The LTC4085EDE-4#PBF incorporates multiple hardware-based thermal protections: (1) thermal regulation that reduces charge current above TJ ≈ 105°C, (2) overtemperature shutdown at TJ > 110°C, and (3) NTC thermistor interface with programmable hot/cold fault thresholds (32.6% × VNTC hot, 73.8% × VNTC cold). These operate independently of external control-ensuring battery safety even if MCU firmware fails. The LTC4085EDE-4#PBF's exposed-pad DFN package further enables reliable heat dissipation.
Is the LTC4085EDE-4#PBF pin-compatible with other LTC4085 variants?
Yes-the LTC4085EDE-4#PBF is pin-compatible with all LTC4085-x variants (e.g., LTC4085EDE-3#PBF, LTC4085EDE#PBF) in the 14-lead DFN package. All share identical pinout, absolute maximum ratings, and electrical characteristics except for float voltage and undervoltage current limit behavior. This allows direct substitution in existing layouts when upgrading to 3.95V float voltage or removing undervoltage current limiting-no PCB changes required.
LTC4085EDE-4#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- PowerPath™
- Package/Case:
- 14-WFDFN Exposed Pad
- Packaging:
- Tube
- Product Status:
- Active
- Battery Chemistry:
- Lithium Ion/Polymer
- Number of Cells:
- 1
- Current - Charging:
- Constant - Programmable
- Programmable Features:
- -
- Fault Protection:
- -
- Charge Current - Max:
- 1.5A
- Battery Pack Voltage:
- 3.95V
- Voltage - Supply (Max):
- 5.5V
- Interface:
- USB
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 14-DFN (4x3)
LTC4085EDE-4#PBF FAQ
1.How can I place an order for LTC4085EDE-4#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC4085EDE-4#PBF on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LTC4085EDE-4#PBF reliable?
The price and inventory of LTC4085EDE-4#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC4085EDE-4#PBF is usually 5 days.
3.What payment methods are accepted for LTC4085EDE-4#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC4085EDE-4#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC4085EDE-4#PBF?
LTC4085EDE-4#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC4085EDE-4#PBF order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LTC4085EDE-4#PBF?
For technical support, including LTC4085EDE-4#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC4085EDE-4#PBF requirements.
6.How does Aetrix verify that LTC4085EDE-4#PBF is sourced from the original manufacturer or authorized distributors?
All LTC4085EDE-4#PBF products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LTC4085EDE-4#PBF meets industry standards.
7.What is the process for return or replacement of LTC4085EDE-4#PBF?
All LTC4085EDE-4#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC4085EDE-4#PBF, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LTC4085EDE-4#PBF part is unused and in its original packaging.
Return procedure for LTC4085EDE-4#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC4085EDE-4#PBF Tags
-
BQ21040DBVR
Texas Instruments
-
MCP73812T-420I/OT
Microchip Technology
-
MCP73831T-2ACI/OT
Microchip Technology
-
MCP73832T-2ACI/OT
Microchip Technology
-
MCP73831T-2DCI/OT
Microchip Technology
-
MCP73832T-2DCI/OT
Microchip Technology
-
MCP73831T-2ATI/OT
Microchip Technology
-
MCP73832T-2ATI/OT
Microchip Technology
-
MCP73831T-5ACI/OT
Microchip Technology
-
MCP73832T-2ACI/MC
Microchip Technology
-
MCP73831T-2ACI/MC
Microchip Technology
-
MCP73831T-2ATI/MC
Microchip Technology
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
