Features and Benefits
- High Efficiency: Up to 95%
- Maximum Current Output: 15mA
- Externally Programmable Frequency Clamp with Internal 50kHz Default Minimizes Audio Noise
- 18μA IQ Current
- 2.9V to 5.5V Input Voltage Range
- Low-Battery Detection
- 0.6V Reference Allows Low Output Voltages
- Shutdown Mode Draws <1μA Supply Current
- 2.8V Undervoltage Lockout
- Unique Low Noise Control Architecture
- Internal Power MOSFETs
- No Schottky Diodes Required
- Internal Soft-Start
- Tiny 2mm × 2mm 8-Lead DFN Package
The LTC3620 is a high efficiency, synchronous buck regulator, suitable for very low power, very small footprint applications powered by a single Li-Ion battery.
The internal synchronous switches increase efficiency and eliminate the need for external Schottky diodes. Low output voltages are easily supported by the 0.6V feedback reference voltage. The LTC3620-1 option is internally programmed to provide a 1.1V output.
The LTC3620 uses a unique variable frequency architecture to minimize power loss and achieve high efficiency. The switching frequency is proportional to the load current, and an internal frequency clamp forces a minimum switching frequency at light loads to minimize noise in the audio range. The user can program the frequency of this clamp by applying an external clock to the FMIN/MODE pin.
The battery status output, LOBATB, indicates when the input voltage drops below 3V. To help prevent damage to the battery, an undervoltage lockout (UVLO) circuit shuts down the part if the input voltage falls below 2.8V.
The LTC3620 is available in a low profile, 2mm × 2mm 8-lead DFN package.
- Hearing Aids
- Wireless Headsets
- Li-Ion Cell Applications
- Button Cell Replacement
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Demonstration circuit 1460A is a high efficiency step-down converter featuring the LTC3620EDC. Its input voltage ranges from 2.9V to 5.5V, and it provides up to 15mA of load current at a jumper-selectable output voltages of 1.1V, 1.2V or 1.8V.
Tools & Simulations
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.
Models for the following parts are available in LTspice:
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.
Sample & Buy
The USA 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. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.