LT1577 - Ultrafast Transient Response, Low Dropout Regulators Adjustable and Fixed


  • UltraFast™ Transient Response Eliminates Tantalum and Electrolytic Output Capacitors
  • FET RDS(ON) Defines Dropout Voltage
  • 1% Reference/Output Voltage Tolerance Over Temperature
  • Typical Load Regulation: 1mV
  • High Side Sense Current Limit
  • Multifunction Shutdown Pin with Latchoff

Typical Application

LT1577 Typical Application
LT1577 Typical Application


The LT1575/LT1577 are single/dual controller ICs that drive low cost external N-channel MOSFETs as source followers to produce ultrafast transient response, low dropout voltage regulators.

The LT1575/LT1577 achieve unprecedented transient-load performance by eliminating expensive tantalum or bulk electrolytic output capacitors in the most demanding modern microprocessor applications. Precision-trimmed adjustable and fixed output voltage versions accommodate any required microprocessor power supply voltage. Selection of the N-channel MOSFET RDS(ON) allows very low dropout voltages to be achieved.

Unique protection features include a high side current limit amplifier that activates a fault protection timer circuit. A multifunction Shutdown pin provides either current limit time-out with latchoff, overvoltage protection, thermal shutdown or a combination of these functions. The LT1575 is available in 8-pin SO or PDIP and the LT1577 is available in 16-pin narrow body SO.


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

Part Number Package Code Temp Package
LT1577CS-3.3/2.8#PBF SO-16 S C 05-08-1610 (S16) Yes
LT1577CS-3.3/2.8#TRPBF SO-16 S C 05-08-1610 (S16) Yes
LT1577CS-3.3/ADJ#PBF SO-16 S C 05-08-1610 (S16) Yes
LT1577CS-3.3/ADJ#TRPBF SO-16 S C 05-08-1610 (S16) Yes
LT1577CS-ADJ/ADJ#PBF SO-16 S C 05-08-1610 (S16) Yes
LT1577CS-ADJ/ADJ#TRPBF SO-16 S C 05-08-1610 (S16) Yes

LT1577 Package Drawing
LT1577 Package Drawing
LT1577 Package Drawing
LT1577 Package Drawing
LT1577 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
LT1577CS-3.3/2.8#PBF SO-16 C $5.40 $4.45 Yes
LT1577CS-3.3/2.8#TRPBF SO-16 C $4.51 Yes
LT1577CS-3.3/ADJ#PBF SO-16 C $5.40 $4.45 Yes
LT1577CS-3.3/ADJ#TRPBF SO-16 C $4.51 Yes
LT1577CS-ADJ/ADJ#PBF SO-16 C $5.40 $4.45 Yes
LT1577CS-ADJ/ADJ#TRPBF SO-16 C $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.

Click here to view our complete list of demo boards


  • Pentium® Processor Supplies
  • PowerPC™ Supplies
  • 5V to 3.XXV or 3.3V to 2.XXV Microprocessor Supplies
  • GTL Termination
  • Low Voltage Logic Supplies

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