Features and Benefits
- Low Noise: 20µVRMS (10Hz to 100kHz)
- Low Quiescent Current: 30µA/Output
- Independent Inputs
- Wide Input Voltage Range: 1.8V to 20V
- Output Current: 100mA/500mA
- Very Low Shutdown Current: <0.1µA
- Low Dropout Voltage: 300mV/320mV at 100mA/500mA
- Adjustable Outputs from 1.22V to 20V
- Stable with as Low as 1µF/3.3µF Output Capacitor
- Stable with Aluminum, Tantalum or Ceramic Capacitors
- Reverse-Battery Protected
- No Protection Diodes Needed
- Overcurrent and Overtemperature Protected
- Tracking/Sequencing Capability
- Thermally Enhanced 16-Lead TSSOP and 16-Lead (5mm × 3mm) DFN Packages
The LT3028 is a dual, micropower, low noise, low dropout regulator with independent inputs. With an external 0.01µF bypass capacitor, output noise is a low 20µVRMS over a 10Hz to 100kHz bandwidth. Designed for use in battery-powered systems, the low 30µA quiescent current per output makes it an ideal choice. In shutdown, quiescent current drops to less than 0.1µA. Shutdown control is independent for each output, allowing for flexibility in power management. The device is capable of operating over an input voltage range of 1.8V to 20V. Output 1 can supply 500mA of output current with a dropout voltage of 320mV. The device can supply 100mA of output current from Output 2 with a dropout voltage of 300mV. Quiescent current is well controlled in dropout.
The LT3028 regulator is stable with output capacitors as low as 1µF for the 100mA output and 3.3µF for the 500mA output. Small ceramic capacitors can be used without the series resistance required by other regulators.
Internal protection circuitry includes reverse-battery protection, current limiting and thermal limiting protection. The device is available as an adjustable device with a 1.22V reference voltage. The LT3028 regulator is available in the thermally enhanced 16-lead TSSOP and 16-lead, low profile (5mm × 3mm × 0.75mm) DFN packages.
- Cellular Phones
- Battery-Powered Systems
- Frequency Synthesizers
- Wireless Modems
- Tracking/Sequencing Power Supplies
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 832 is a dual output, dual input regulator consisting of two LDO linear regulators, based on the LT3028 monolithic linear regulator in the 5×3 DFN-16 package. Each independent input has a voltage range of 2.3V to 20V, with one output (VOUT1) capable of delivering up to 500mA of output current, and the other output (VOUT2) capable of delivering up to 100mA of output current. The two output voltages are set independently with jumpers; each can be set to 2.5V, 3.3V, 5V or a user-defined value (two jumper options for this).
The DC quiescent current is typically only 50uA (for the entire IC) at no load.
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.