Overview
Features and Benefits
- Low Output Noise: 60µVRMS (100kHz BW)
- Adjustable or Fixed Boosted Output
- Adjustable Output Voltage Range: 2.5V to 5.5V
- Fixed Output Voltages: 3.3V, 5V
- Wide Input Voltage Range: 1.8V to 4.4V
- Uses Small Ceramic Capacitors
- No Inductors Required
- Output Current up to 50mA
- 550kHz Switching Frequency
- Low Operating Current: 150µA
- Low Shutdown Current: 1µA
- Internal Thermal Shutdown and Current Limiting
- Available in 8-Pin MSOP and SO Packages
Product Details
The LTC1682/LTC1682-3.3/LTC1682-5 are doubler charge pumps with an internal low noise, low dropout (LDO) linear regulator. These parts are designed to provide a low noise boosted supply voltage for powering noise sensitive devices such as high frequency VCOs in wireless applications.
An internal doubler charge pump converts a 1.8V to 4.4V input to a boosted output, while the internal LDO regulator converts the boosted voltage to a low noise regulated output. The adjustable version allows the user to set VOUT via external resistors connected to FB. The regulator is capable of supplying up to 50mA of output current. Shutdown reduces the supply current to < 5µA, removes the load from VIN by disabling the regulator and discharges VOUT to ground through a 100Ω switch.
The LTC1682 LDO regulator is stable with only 2µF on the output. Small ceramic capacitors can be used, reducing PC board area.
The LTC1682/LTC1682-3.3/LTC1682-5 are short-circuit and over temperature protected. The parts are available in 8-pin MSOP and SO packages.
Applications
- VCO Power Supplies in Cellular Phones
- 2-Way Pagers
- Wireless PCMCIA Cards
- Portable Medical Instruments
- Low Power Data Acquisition
- Remote Transmitters
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 (4)
Documentation
Reliability Data (1)
Evaluation Kit Manuals (2)
Design Notes (1)
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:
Reference Materials
Technical Articles (1)
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.
PCN-PDN Information
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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.