LTC3388 - 20V High Efficiency Nanopower Step-Down Regulator


  • 720nA Input IQ in Regulation (No Load), VIN = 4V
  • 820nA Input IQ in Regulation (No Load), VIN = 20V
  • 400nA Input IQ in UVLO
  • 2.7V to 20V Input Operating Range
  • Up to 50mA of Output Current
  • Pin Selectable Output Voltages:
    1.2V, 1.5V, 1.8V, 2.5V (LTC3388-1)
    2.8V, 3.0V, 3.3V, 5.0V (LTC3388-3)
  • High Efficiency Hysteretic Synchronous DC/DC Conversion
  • Standby Mode Disables Buck Switching
  • Available in 10-Lead MSE and 3mm × 3mm DFN Packages

Typical Application

LTC3388 Typical Application
LTC3388 Typical Application


The LTC3388-1/LTC3388-3 are high efficiency step-down DC/DC converters with internal high side and synchronous power switches that draw only 720nA typical DC supply current at no load while maintaining output voltage regulation.

Capable of supplying 50mA of load current, the LTC3388-1/ LTC3388-3 also incorporate an accurate undervoltage lockout (UVLO) feature to disable the converter and maintain a low quiescent current state when the input voltage falls below 2.3V. In regulation, the LTC3388-1/LTC3388-3 enter a sleep state in which both input and output quiescent currents are minimal. The buck converter turns on and off as needed to maintain regulation. An additional standby mode disables buck switching while the output is in regulation for short duration loads requiring low ripple.

Output voltages of 1.2V, 1.5V, 1.8V, 2.5V (LTC3388-1) and 2.8V, 3.0V, 3.3V, 5.0V (LTC3388-3) are pin selectable. The LTC3388-1/LTC3388-3 can operate with VIN up to 20V while the no load quiescent current remains below 1μA.


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
LTC3388EDD-1#PBF 3x3 DFN-10 DD E 05-08-1699 Yes
LTC3388EDD-1#TRPBF 3x3 DFN-10 DD E 05-08-1699 Yes
LTC3388EDD-3#PBF 3x3 DFN-10 DD E 05-08-1699 Yes
LTC3388EDD-3#TRPBF 3x3 DFN-10 DD E 05-08-1699 Yes
LTC3388EMSE-1#PBF MS-10E MSE E 05-08-1664 Yes
LTC3388EMSE-1#TRPBF MS-10E MSE E 05-08-1664 Yes
LTC3388EMSE-3#PBF MS-10E MSE E 05-08-1664 Yes
LTC3388EMSE-3#TRPBF MS-10E MSE E 05-08-1664 Yes
LTC3388IDD-1#PBF 3x3 DFN-10 DD I 05-08-1699 Yes
LTC3388IDD-1#TRPBF 3x3 DFN-10 DD I 05-08-1699 Yes
LTC3388IDD-3#PBF 3x3 DFN-10 DD I 05-08-1699 Yes
LTC3388IDD-3#TRPBF 3x3 DFN-10 DD I 05-08-1699 Yes
LTC3388IMSE-1#PBF MS-10E MSE I 05-08-1664 Yes
LTC3388IMSE-1#TRPBF MS-10E MSE I 05-08-1664 Yes
LTC3388IMSE-3#PBF MS-10E MSE I 05-08-1664 Yes
LTC3388IMSE-3#TRPBF MS-10E MSE I 05-08-1664 Yes

LTC3388 Package Drawing
LTC3388 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
LTC3388EDD-1#PBF 3x3 DFN-10 E $4.22 $2.95 Yes
LTC3388EDD-1#TRPBF 3x3 DFN-10 E $3.01 Yes
LTC3388EDD-3#PBF 3x3 DFN-10 E $4.22 $2.95 Yes
LTC3388EDD-3#TRPBF 3x3 DFN-10 E $3.01 Yes
LTC3388EMSE-1#PBF MS-10E E $4.22 $2.95 Yes
LTC3388EMSE-1#TRPBF MS-10E E $3.01 Yes
LTC3388EMSE-3#PBF MS-10E E $4.22 $2.95 Yes
LTC3388EMSE-3#TRPBF MS-10E E $3.01 Yes
LTC3388IDD-1#PBF 3x3 DFN-10 I $4.96 $3.47 Yes
LTC3388IDD-1#TRPBF 3x3 DFN-10 I $3.53 Yes
LTC3388IDD-3#PBF 3x3 DFN-10 I $4.96 $3.47 Yes
LTC3388IDD-3#TRPBF 3x3 DFN-10 I $3.53 Yes
LTC3388IMSE-1#PBF MS-10E I $4.96 $3.47 Yes
LTC3388IMSE-1#TRPBF MS-10E I $3.53 Yes
LTC3388IMSE-3#PBF MS-10E I $4.96 $3.47 Yes
LTC3388IMSE-3#TRPBF MS-10E I $3.53 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
DC1658A-A LTC3388EMSE-1 Demo Board | 2.7V ≤ VIN ≤ 20V, VOUT = 1.2V to 2.5V @ 50mA $175.00
DC1658A-B LTC3388EMSE-3 Demo Board | 2.8V ≤ VIN ≤ 20V, VOUT = 2.8V to 5V @ 50mA $175.00
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