LT3585 - Photoflash Charger with Adjustable Input Current and IGBT Driver


  • Adjustable Input Current
  • Integrated IGBT Driver
  • No Output Voltage Divider Needed
  • Uses Small Transformers: 5.8mm × 5.8mm × 3mm
  • Fast Photoflash Charge Times
  • Charges Any Size Photoflash Capacitor
  • Supports Operation from Single Li-Ion Cell, Two AA
  • Cells or any Supply from 1.5V Up to 16V
  • Small 10-Lead (3mm × 2mm) DFN Package

Typical Application

LT3585 Typical Application
LT3585 Typical Application


The LT3585 series are highly integrated ICs designed to charge photoflash capacitors in digital and film cameras. A new control technique allows for the use of extremely small transformers. Each part contains an on-chip high voltage NPN power switch. Output voltage detection is completely contained within the part, eliminating the need for any discrete zener diodes or resistors. The output voltage can be adjusted by simply changing the turns ratio of the transformer.

The CHRG/IADJ pin gives full control of the part to the user. Driving CHRG/IADJ low puts the part in low power shutdown. The CHRG/IADJ pin can also be used to reduce the input current of the charger, useful in extending battery life. The DONE pin indicates when the part has completed charging.

The LT3585 series of parts are housed in tiny 3mm × 2mm DFN packages.


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
LT3585EDDB-0#PBF 3x2 DFN-10 DDB E 05-08-1722 Yes
LT3585EDDB-0#TRPBF 3x2 DFN-10 DDB E 05-08-1722 Yes
LT3585EDDB-1#PBF 3x2 DFN-10 DDB E 05-08-1722 Yes
LT3585EDDB-1#TRMPBF 3x2 DFN-10 DDB E 05-08-1722 Yes
LT3585EDDB-1#TRPBF 3x2 DFN-10 DDB E 05-08-1722 Yes
LT3585EDDB-2#PBF 3x2 DFN-10 DDB E 05-08-1722 Yes
LT3585EDDB-2#TRMPBF 3x2 DFN-10 DDB E 05-08-1722 Yes
LT3585EDDB-2#TRPBF 3x2 DFN-10 DDB E 05-08-1722 Yes
LT3585EDDB-3#TRMPBF 3x2 DFN-10 DDB E 05-08-1722 Yes
LT3585EDDB-3#TRPBF 3x2 DFN-10 DDB E 05-08-1722 Yes

LT3585 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
LT3585EDDB-0#PBF 3x2 DFN-10 E $1.57 Yes
LT3585EDDB-0#TRPBF 3x2 DFN-10 E $1.57 $1.15 Yes
LT3585EDDB-1#PBF 3x2 DFN-10 E $1.57 Yes
LT3585EDDB-1#TRMPBF 3x2 DFN-10 E $1.57 $1.10 Yes
LT3585EDDB-1#TRPBF 3x2 DFN-10 E $1.57 $1.15 Yes
LT3585EDDB-2#PBF 3x2 DFN-10 E $1.57 Yes
LT3585EDDB-2#TRMPBF 3x2 DFN-10 E $1.57 $1.20 Yes
LT3585EDDB-2#TRPBF 3x2 DFN-10 E $1.57 $1.15 Yes
LT3585EDDB-3#TRMPBF 3x2 DFN-10 E $1.57 $1.20 Yes
LT3585EDDB-3#TRPBF 3x2 DFN-10 E $1.57 $1.15 Yes
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* 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
DC988A-A LT3485EDD-0 | Photoflash Charger, 500mA Input Current, Vin=2.8V-4.2V, Vbat=1.8V-4.2V, 5V Max $100.00
DC988A-B LT3585EDDB-1 | 250mA I input Photoflash Charger with Adjustable Input Current Limit and Integrated IGBT Driver $100.00
DC988A-C LT3585EDDB-2 | 400mA I input Photoflash Charger with Adjustable Input Current Limit and Integrated IGBT Driver $100.00
DC988A-D LT3585EDDB-3 | 800mA I input Photoflash Charger with Adjustable Input Current Limit and Integrated IGBT Driver $100.00
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Click here to view our complete list of demo boards


  • Digital/Film Camera Flash
  • PDA/Cell Phone Flash
  • Emergency Strobe

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Design Tools


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