Overview
Features and Benefits
- Wireless Li-Ion Battery Charger Plus High Efficiency Multi-Mode Charge Pump DC/DC
- Programmable Charge Current from 1mA to 50mA Via an External Resistor
- Wideband Rx Frequency: DC to >10MHz
- Integrated Rectifier with Overvoltage Limit
- Charge Voltage: 4.2V
- Low Battery Disconnect: 3.0V
- NTC Pin for Temperature Qualified Charging
- DC/DC Regulated Output: 1.2V
- DC/DC Output Current: Up to 60mA
- 50kHz/75kHz Switching, No Audible Noise
- Pushbutton and/or Digital on/off Control for DC/DC
- Thermally Enhanced 12-Lead 2mm × 2mm LQFN Package
Product Details
The LTC4126-ADJ is a low-power wireless single-cell Li-Ion battery charger with an integrated step-down DC/DC regulator. The step-down regulator is a low-noise multimode charge pump which is powered from the battery and provides a regulated 1.2V at the output. The switching frequency is set to either 50kHz or 75kHz depending on the mode to keep any switching noise out of the audible range.
The constant-current constant-voltage Li-Ion battery charger has automatic recharge, automatic termination by safety timer, and battery temperature monitoring via an NTC pin. Charge current is programmable from 1mA to 50mA via an external resistor. Undervoltage protection disconnects the battery from all loads when the battery voltage is below 3.0V.
The small package and minimal external component count make the LTC4126-ADJ and its variants suitable for hearing aid applications and other low power portable devices. See the chart in the data sheet.
APPLICATIONS
- Hearing Aids
- Low Power Li-Ion Powered Devices
- Wireless Headsets
- IoT Wearables
Product Categories
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 (1)
Documentation & Resources
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.

Models for the following parts are available in LTspice:
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 |
---|---|---|---|---|
LTC4126EV-ADJ#TRMPBF | Material Declaration | Reliability Data | 12-Lead LQFN (2mm x 2mm x 0.74mm) | |
LTC4126EV-ADJ#TRPBF | Material Declaration | Reliability Data | 12-Lead LQFN (2mm x 2mm x 0.74mm) | |
Wafer Fabrication Data |
Support & 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.