LTC3805-5
PRODUCTIONAdjustable Frequency Current Mode Flyback/Boost/SEPIC DC/DC Controller
- Part Models
- 12
- 1ku List Price
- Starting From $2.17
Overview
- VIN and VOUT Limited Only by External Components
- 4.5V Undervoltage Lockout Threshold
- Adjustable Slope Compensation
- Adjustable Overcurrent Protection with Automatic Restart
- Adjustable Operating Frequency (70kHz to 700kHz) With One External Resistor
- Synchronizable to an External Clock
- ±1.5% Reference Accuracy
- Only 100mV Current Sense Voltage Drop
- RUN Pin with Precision Threshold and Adjustable Hysteresis
- Programmable Soft-Start with One External Capacitor
- Low Quiescent Current: 360μA
- Small 10-Lead MSOP and 3mm × 3mm DFN
The LTC3805-5 is a current mode DC/DC controller designed to drive an N-channel MOSFET in flyback, boost and SEPIC converter applications. Operating frequency and slope compensation can be programmed by external resistors. Programmable overcurrent sensing protects the converter from overload and short-circuit conditions. Soft-start can be programmed using an external capacitor and the soft-start capacitor also programs an automatic restart feature.
The LTC3805-5 provides ±1.5% output voltage accuracy and consumes only 360μA of quiescent current during normal operation and only 40μA during micropower startup. Using a 9.5V internal shunt regulator, the LTC3805-5 can be powered from a high VIN through a resistor or it can be powered directly from a low impedance DC voltage from 4.7V to 8.8V.
The LTC3805-5 is available in the 10-lead MSOP package and the 3mm × 3mm DFN package.
| Turn On Voltage | |
| LTC3805 | 8.4V |
| LTC3805-5 | 4.5V |
Applications
- Automotive Power Supplies
- Telecom Power Supplies
- Isolated Electronic Equipment
- Auxiliary/Housekeeping Power Supplies
- Power over Ethernet
Documentation
Data Sheet 1
User Guide 2
Design Note 2
Technical Articles 1
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal. View our quality and reliability program and certifications for more information.
| Part Model | Pin/Package Drawing | Documentation | CAD Symbols, Footprints, and 3D Models |
|---|---|---|---|
| LTC3805EDD-5#PBF | 10-Lead DFN (3mm x 3mm w/ EP) | ||
| LTC3805EDD-5#TRPBF | 10-Lead DFN (3mm x 3mm w/ EP) | ||
| LTC3805EMSE-5#PBF | 10-Lead MSOP w/ EP | ||
| LTC3805EMSE-5#TRPBF | 10-Lead MSOP w/ EP | ||
| LTC3805HMSE-5#PBF | 10-Lead MSOP w/ EP | ||
| LTC3805HMSE-5#TRPBF | 10-Lead MSOP w/ EP | ||
| LTC3805IDD-5#PBF | 10-Lead DFN (3mm x 3mm w/ EP) | ||
| LTC3805IDD-5#TRPBF | 10-Lead DFN (3mm x 3mm w/ EP) | ||
| LTC3805IMSE-5#PBF | 10-Lead MSOP w/ EP | ||
| LTC3805IMSE-5#TRPBF | 10-Lead MSOP w/ EP | ||
| LTC3805MPMSE-5#PBF | 10-Lead MSOP w/ EP | ||
| LTC3805MPMSE-5#TRPBF | 10-Lead MSOP w/ EP |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
Feb 4, 2020 - 20_0130 Laser Top Mark Conversion for 10-Lead MSOP Packages Assembled in ADPG and UTAC |
||
| LTC3805EMSE-5#PBF | PRODUCTION | |
| LTC3805EMSE-5#TRPBF | PRODUCTION | |
| LTC3805HMSE-5#PBF | PRODUCTION | |
| LTC3805HMSE-5#TRPBF | PRODUCTION | |
| LTC3805IMSE-5#PBF | PRODUCTION | |
| LTC3805IMSE-5#TRPBF | PRODUCTION | |
| LTC3805MPMSE-5#PBF | PRODUCTION | |
| LTC3805MPMSE-5#TRPBF | PRODUCTION | |
|
Oct 11, 2022 - 22_0244 Epoxy Change from Henkel 8290 to 8290A for MSOP Package |
||
| LTC3805IMSE-5#PBF | PRODUCTION | |
| LTC3805IMSE-5#TRPBF | PRODUCTION | |
| LTC3805MPMSE-5#PBF | PRODUCTION | |
| LTC3805MPMSE-5#TRPBF | PRODUCTION | |
|
Jul 12, 2022 - 22_0157 UTAC Thai Limited (UTL) as Alternate Assembly Site for MSOP Packages [With Modification in BOM] |
||
| LTC3805IMSE-5#PBF | PRODUCTION | |
| LTC3805IMSE-5#TRPBF | PRODUCTION | |
|
Jun 21, 2022 - 22_0050 UTAC Thai Limited (UTL) as Alternate Assembly Site for MSOP Packages / Devices |
||
| LTC3805IMSE-5#PBF | PRODUCTION | |
| LTC3805IMSE-5#TRPBF | PRODUCTION | |
This is the most up-to-date revision of the Data Sheet.
Software Resources
Can't find the software or driver you need?
Request a Driver/SoftwareHardware Ecosystem
Tools & Simulations
LTspice 2
- LTC3805-5 Demo Circuit - Adjustable Frequency Current Mode Flyback Controller (18-36V to -100V @ 50mA)
- LTC3805-5 & LT1797 Demo Circuit - Positive-to-Negative Cuk Converter (8-16V to -12V @ 3A)
Models for the following parts are available in LTspice:
- LTC3805
- LTC3805-5
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
Evaluation Kits
Latest Discussions
No discussions on LTC3805-5 yet. Have something to say?
Start a Discussion on EngineerZone®