LTC3623 - 15V, ±5A Rail-to-Rail Synchronous Buck Regulator


  • Single Resistor Programmable VOUT: 0V to VIN – 0.5V
  • Silent Switcher® Architecture
  • IISET Accuracy: ±1%
  • Tight VOUT Regulation Across VOUT Range
  • Output Current Monitor Accuracy: ±5%
  • Programmable Wire Drop Compensation
  • Easy to Parallel for Higher Current and Heat Spreading
  • Input Supply Voltage Regulation Loop
  • High Efficiency: Up to 96%
  • Output Current: ±5A
  • Integrated N-MOSFETs (60mΩ Top & 30mΩ Bottom)
  • Adjustable Switching Frequency: 400KHz to 4MHz
  • VIN Range: 4V to 15V
  • Current Mode Operation for Excellent Line and Load Transient Response
  • Shutdown Mode Draws Less Than 1µA Supply Current
  • Low Profile 24-Lead 3mm × 5mm QFN Package

Typical Application

LTC3623 Typical Application
LTC3623 Typical Application


TheLTC3623 is a high efficiency, monolithic synchronous buck regulator in which the output voltage is programmed with a single external resistor. The accurate internally generated 50µA current source on the ISET pin allows the user to program an output voltage from 0V to 0.5V below VIN. The user can also directly drive the ISET pin with an external voltage supply to program the converter’s VOUT. The VOUT voltage is fed directly back to the error amplifier to be regulated to the ISET voltage. The operating supply voltage range for the SVIN pin is from 15V down to 4V, while the PVIN pin’s voltage range is 15V down to 1.5V, making it suitable for dual Li-Ion batteries and for taking power from a 12V or 5V rail.

The operating frequency is programmable from 400KHz to 4MHz with an external RT resistor. Higher switching frequencyallowstheuseofsmallersurfacemountinductors while lower frequency allows for higher power efficiency. The unique constant-frequency/controlled on-time architecture is ideal for high step-down ratio applications that are operating at high frequency while demanding fast transient response.


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

Part Number Package Code Temp Package
LTC3623EUDD#PBF 3x5 QFN-24 UDD E 05-08-1833 Yes
LTC3623EUDD#TRPBF 3x5 QFN-24 UDD E 05-08-1833 Yes
LTC3623IUDD#PBF 3x5 QFN-24 UDD I 05-08-1833 Yes
LTC3623IUDD#TRPBF 3x5 QFN-24 UDD I 05-08-1833 Yes

LTC3623 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
LTC3623EUDD#PBF 3x5 QFN-24 E $5.64 $3.95 Yes
LTC3623EUDD#TRPBF 3x5 QFN-24 E $5.70 $4.01 Yes
LTC3623IUDD#PBF 3x5 QFN-24 I $6.36 $4.45 Yes
LTC3623IUDD#TRPBF 3x5 QFN-24 I $6.42 $4.51 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
DC2131A LTC3623 Demo Board | Silent Switcher Sync Buck, 4V ≤ VIN ≤ 15V, Vout = 1V/1.5V/2.5V/3.3V/5V @ ±5A $349.00
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