LTC3230 - 5-LED Main/Sub Display Driver with Dual LDO


  • Low Noise Charge Pump Provides High Efficiency with Automatic Mode Switching
  • Multimode Operation: 1x, 1.5x, 2x
  • Full-Scale Current Set Resistor
  • Up to 125mA Total LED Current
  • Single Wire Enable/Brightness Control for Main and Sub Display LEDs
  • 32:1 Linear LED Brightness Control
  • Dual 200mA Linear Regulators
  • Four 25mA Low Dropout Main LED Current Sources
  • One 25mA Low Dropout Sub LED Current Source
  • Low Noise Constant Frequency Operation
  • Low Shutdown Current: 3µA
  • Internal Soft-Start Limits Inrush Current During Start-Up and Mode Switching
  • Open/Short LED Protection
  • No Inductors
  • 20-Lead 3mm x 3mm QFN Package

Typical Application

LTC3230 Typical Application
LTC3230 Typical Application


The LTC3230 is a low noise charge pump DC/DC converter designed to drive 4 Main LEDs and 1 Sub LED, plus two 200mA linear regulators to provide additional system power. The LTC3230 charge pump requires only four small ceramic capacitors and one current set resistor to form a complete LED power supply and current controller.
Built-in soft-start circuitry prevents excessive inrush cur- rent during start-up and mode changes. High switching frequency enables the use of small external capacitors. Main and Sub full-scale current settings are programmed by a single external resistor.
Charge pump efficiency is optimized based on the voltage across the LED current sources. The part powers up in 1x mode and automatically switches to the next higher mode, 1.5x and subsequently 2x, whenever any LED current source approaches dropout.
Two 200mA linear regulators have independent enable and output voltage select pins. Each regulator can be set to one of three pre-selected output voltages with tri-level input pins. The regulators may be enabled independently of the charge pump.
The LTC3230 is available in a low profile (0.75mm) 3mm x 3mm 20-lead QFN package.


CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
LTC3230EUD#PBF 3x3 QFN-20 UD E 05-08-1720 Yes
LTC3230EUD#TRPBF 3x3 QFN-20 UD E 05-08-1720 Yes

LTC3230 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
LTC3230EUD#PBF 3x3 QFN-20 E $2.21 $1.55 Yes
LTC3230EUD#TRPBF 3x3 QFN-20 E $1.61 Yes
Buy NowRequest Samples
* 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 Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC1217A LTC3230EUD | 5-LED Main/Aux Drv + Dual LDO in 3x3 QFN Contact Factory
Buy Now

Companion Boards

Part Number Description Price Documentation
DC590B Isolated USB Serial Controller for Linear Technology QuikEval-Compatible Demo Boards $50.00
Buy Now
Click here to view our complete list of demo boards


  • Multi-LED Driver and Dual LDO Supplies for Cell Phone, PDA, Digital Camera and PND Applications

Product Notifications

Please login to your MyLinear account for notifications of datasheet updates, new document releases and LTspice model announcements for your favorite products. If you do not have a MyLinear account you may Sign Up Now.

Forgot your password? Click here.
Need help? Email with questions and comments.

Design Tools


LTspice® software is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. Click here to download LTspice

Models for the following parts are available in LTspice:

Technical Support