LT1765 - Monolithic 3A, 1.25MHz Step-Down Switching Regulators
Features
- 3A Switch in a Thermally Enhanced 16-Lead TSSOP or 8-Lead SO Package
- Constant 1.25MHz Switching Frequency
- Wide Operating Voltage Range: 3V to 25V
- High Efficiency 0.09Ω Switch
- 1.2V Feedback Reference Voltage
- Uses Low Profile Surface Mount Components
- Low Shutdown Current: 15µA
- Synchronizable to 2MHz
- Current Mode Loop Control
- Constant Maximum Switch Current Rating at All Duty Cycles*
- Available in 8-Lead SO and 16-Lead Thermally Enhanced TSSOP Packages
Typical Application
Description
The LT1765 is a 1.25MHz monolithic buck switching regulator. A high efficiency 3A, 0.09Ω switch is included on the die together with all the control circuitry required to construct a high frequency, current mode switching regulator. Current mode control provides fast transient response and excellent loop stability.
New design techniques achieve high efficiency at high switching frequencies over a wide operating voltage range. A low dropout internal regulator maintains consistent performance over a wide range of inputs from 24V systems to Li-Ion batteries. An operating supply current of 1mA improves efficiency, especially at lower output currents. Shutdown reduces quiescent current to 15µA. Maximum switch current remains constant at all duty cycles. Synchronization allows an external logic level signal to increase the internal oscillator into the range of 1.6MHz to 2MHz.
Full cycle-by-cycle current control and thermal shutdown are provided. High frequency operation allows the reduction of input and output filtering components and permits the use of chip inductors.
Packaging
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 Drawing |
RoHS |
|---|---|---|---|---|---|
| LT1765EFE-1.8#PBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765EFE-1.8#TRPBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765EFE-2.5#PBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765EFE-2.5#TRPBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765EFE-3.3#PBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765EFE-3.3#TRPBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765EFE-5#PBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765EFE-5#TRPBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765EFE#PBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765EFE#TRPBF | TSSOP-16 | FE | E | 05-08-1663 (BB) | Yes |
| LT1765ES8#PBF | SO-8 | S8 | E | 05-08-1610 (S8) | Yes |
| LT1765ES8#TRPBF | SO-8 | S8 | E | 05-08-1610 (S8) | Yes |
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 (1-99) |
Price (1k)* |
RoHS | |
|---|---|---|---|---|---|---|
| LT1765EFE-1.8#PBF | TSSOP-16 | E | $6.89 | $4.82 | Yes | |
| LT1765EFE-1.8#TRPBF | TSSOP-16 | E | $4.94 | Yes | ||
| LT1765EFE-2.5#PBF | TSSOP-16 | E | $6.89 | $4.82 | Yes | |
| LT1765EFE-2.5#TRPBF | TSSOP-16 | E | $4.94 | Yes | ||
| LT1765EFE-3.3#PBF | TSSOP-16 | E | $6.89 | $4.82 | Yes | |
| LT1765EFE-3.3#TRPBF | TSSOP-16 | E | $4.94 | Yes | ||
| LT1765EFE-5#PBF | TSSOP-16 | E | $6.89 | $4.82 | Yes | |
| LT1765EFE-5#TRPBF | TSSOP-16 | E | $4.94 | Yes | ||
| LT1765EFE#PBF | TSSOP-16 | E | $6.89 | $4.82 | Yes | |
| LT1765EFE#TRPBF | TSSOP-16 | E | $4.94 | Yes | ||
| LT1765ES8#PBF | SO-8 | E | $5.53 | $4.67 | Yes | |
| LT1765ES8#TRPBF | SO-8 | E | $4.73 | Yes | ||
| Buy Now • Request Samples | ||||||
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 |
|---|---|---|---|
| DC436A | LT1765ES8 | Wide Input Range, 1.25MHz Step-Down DC/DC Converter, 8.5V~25Vin, 5Vout @ 2A | $100.00 | |
| DC476A | LT1765EFE | Wide Input Range, 1.25MHz Step-Down DC/DC Converter, 3V to 25V Input, Jumper Selectable 3.3V or 5Vout @ 2A | $100.00 | |
| Buy Now | |||
Applications
- DSL Modems
- Portable Computers
- Regulated Wall Adapters
- Battery-Powered Systems
- Distributed Power
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Design Tools
LTspice
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LT1765
Technical Support
- For immediate technical assistance, contact your local sales office or distributor or call 1-800-4-LINEAR (US customers only) or 408-432-1900.
- For less urgent requests, please complete our Technical Support Request Form. Please allow 2-3 business days for reply.
