LTC3256 - Wide VIN Range Dual Output 350mA Step-Down Charge Pump with Watchdog Timer
Datasheet Documentation
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Typical Application

LTC3256 Typical Application
LTC3256 Typical Application


The LTC3256 is a wide input range switched capacitor step-down DC/DC converter that produces two regulated outputs: a 5V output via direct connection to the charge pump output, and a 3.3V output via a low dropout (LDO) linear post-regulator. The device provides up to 350mA of total output current. At 12V VIN and maximum load on both outputs, power dissipation is reduced by over 2W compared to a dual LDO regulator solution.

The LTC3256 maximizes efficiency by running the charge pump in 2:1 mode over as wide an operating range as pos- sible, and automatically switches to 1:1 mode as needed due to V IN and load conditions. Controlled input current and switching slew rates minimize conducted and radiated EMI. An integrated watchdog timer, independent power good outputs and reset input ensure reliable system operation and fault monitoring. A buffered 1.1V reference output enables system self-testing for safety critical applications.

The LTC3256 has numerous safety features including overcurrent fault protection, overtemperature protection and tolerance of 38V input transients. The LTC3256 is available in a thermally enhanced 16-lead MSOP plastic package with exposed pad (MSE16).



LTC3256 Package Drawing
Order Info

Package Variations and Pricing

Part Number Package Pins Temp Price
LTC3256MPMSE#PBF MSOP 16 MP $11.36 $7.95
LTC3256HMSE#TRPBF MSOP 16 H $5.35 $3.76
LTC3256EMSE#PBF MSOP 16 E $4.22 $2.95
LTC3256EMSE#TRPBF MSOP 16 E $4.28 $3.01
LTC3256IMSE#PBF MSOP 16 I $4.79 $3.35
LTC3256IMSE#TRPBF MSOP 16 I $4.85 $3.41
LTC3256HMSE#PBF MSOP 16 H $5.29 $3.70
LTC3256MPMSE#TRPBF MSOP 16 MP $11.42 $8.01
* 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
DC2375A LTC3256 Demo Board | Dual Output Step-Down Charge Pump Plus LDO, 5.5V ≤ VIN ≤ 38V, Vout1 = 5V @ 100mA, Vout2 = 3.3V @ 250mA $100.00