Alternative Parts
Overview
Features and Benefits
- Dynamic Harmonization Control Optimizes Wireless Charging Over a Wide Coupling Range
- Wide Input Voltage Range (12.5V to 40V)
- Adjustable Float Voltage (3.5V to 11V)
- Fixed 4.2V Float Voltage Option (LTC4120-4.2)
- 50mA to 400mA Charge Current Programmed with a Single Resistor
- ±1% Feedback Voltage Accuracy
- Programmable 5% Accurate Charge Current
- No Microprocessor Required
- No Transformer Core
- Thermally Enhanced, Low Profile 16-Lead (3mm × 3mm × 0.75mm) QFN Package
Product Details
The LTC4120 is a constant-current/constant-voltage wireless receiver and battery charger. An external programming resistor sets the charge current up to 400mA. The LTC4120-4.2 is suitable for charging Li-Ion/Polymer batteries, while the programmable float voltage of the LTC4120 accommodates several battery chemistries. The LTC4120 uses a Dynamic Harmonization Control (DHC) technique that allows high efficiency contactless charging across an air gap.
The LTC4120 regulates its input voltage via the DHC pin. This technique modulates the resonant frequency of a receiver tank to automatically adjust the power received as well as the power transmitted to provide an efficient solution for wirelessly charging battery-powered devices.
Wireless charging with the LTC4120 provides a method to power devices in harsh environments without requiring expensive failure-prone connectors. This allows products to be charged while locked within sealed enclosures, or in moving or rotating equipment, or where cleanliness or sanitation is critical.
This full featured battery charger includes accurate RUN pin threshold, low voltage battery preconditioning and bad battery fault detection, timer termination, auto-recharge, and NTC temperature qualified charging. The FAULT pin provides an indication of bad battery or temperature faults.
Once charging is terminated, the LTC4120 signals end-of-charge via the CHRG pin, and enters a low current sleep mode. An auto-restart feature starts a new charging cycle if the battery voltage drops by 2.2%.
Applications
- Handheld Instruments
- Industrial/Military Sensors and Devices
- Harsh Environments
- Portable Medical Devices
- Physically Small Devices
- Electrically Isolated Devices
Product Categories
Markets and Technologies
Product Lifecycle
Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (3)
Documentation & Resources
-
R577 Reliability Data3/23/2018
-
Reverse Voltage Protection for Battery Chargers6/1/2020
-
AN-138: Wireless Power User Guide1/1/2019
-
AN138 - Wireless Power User Guide12/19/2014
-
DC2386A - Demo Manual3/9/2016
-
DC2181A - Demo Manual8/28/2015
-
Wireless Power Transfer ICs9/29/2016
-
400mA Wireless Power Receiver & Buck Battery Charger10/25/2013
-
Complete Wireless Charging2/10/2016
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.

LTspice Simulations
Models for the following parts are available in LTspice:
Product Recommendations
LTC4120 Companion Parts
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.
Part Number | Material Declaration | Reliability Data | Pin/Package Drawing | CAD Symbols, Footprints & 3D Models |
---|---|---|---|---|
LTC4120EUD#PBF | Material Declaration | Reliability Data | 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP) | |
LTC4120EUD#TRPBF | Material Declaration | Reliability Data | 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP) | |
LTC4120EUD-4.2#PBF | Material Declaration | Reliability Data | 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP) | |
LTC4120EUD-4.2#TRPBF | Material Declaration | Reliability Data | 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP) | |
LTC4120IUD#PBF | Material Declaration | Reliability Data | 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP) | |
LTC4120IUD#TRPBF | Material Declaration | Reliability Data | 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP) | |
LTC4120IUD-4.2#PBF | Material Declaration | Reliability Data | 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP) | |
LTC4120IUD-4.2#TRPBF | Material Declaration | Reliability Data | 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP) | |
Wafer Fabrication Data | R577 Reliability Data |
Support & Discussions
LTC4120 Discussions
Sample & Buy
Ordering FAQs
See our Ordering FAQs for answers to questions about online orders, payment options and more.
Buy Now Pricing
(**) Displayed Buy Now Price and Price Range is based on small quantity orders.
List Pricing
(*)The 1Ku list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
Lead Times
Please see the latest communication from our CCO regarding lead times.
Sampling
A Sample link will be shown above, next to the part, only for parts that are included in our sample program. Selecting the Sample button will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.
Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.