LT1959
PRODUCTION4.5A, 500kHz Step-Down Switching Regulator
- Part Models
- 8
- 1ku List Price
- Starting From $6.93
Overview
- Operates with Input as Low as 4V
- Output Range Down to 1.21V
- Constant 500kHz Switching Frequency
- Uses All Surface Mount Components
- Inductor Size Reduced to 1.8µH
- Saturating Switch Design: 0.07Ω
- Shutdown Current: 20µA
- Easily Synchronizable
- Cycle-by-Cycle Current Limiting
- 4.5A Switch
- Current Mode Control
The LT1959 is a 500kHz monolithic buck mode switching regulator functionally identical to the LT1506 but optimized for lower output voltage applications. It will operate down to 1.21V output compared to 2.42V for the LT1506. A 4.5A switch is included on the die along with all the necessary oscillator, control and logic circuitry. High switching frequency allows a considerable reduction in the size of external components. The topology is current mode for fast transient response and good loop stability.
A special high speed bipolar process and new design techniques achieve high efficiency at high switching frequency. Efficiency is maintained over a wide output current range by keeping quiescent supply current to 4mA and by utilizing a supply boost capacitor to saturate the power switch.
The LT1959 fits into standard 7-pin DD and fused lead SO-8 packages. Full cycle-by-cycle short-circuit protection and thermal shutdown are provided. Standard surface mount external parts are used, including the inductor and capacitors. There is the optional function of shutdown or synchronization. A shutdown signal reduces supply current to 20µA. Synchronization allows an external logic level signal to increase the internal oscillator from 580kHz to 1MHz.
Applications
- Portable Computers
- Battery-Powered Systems
- Battery Chargers
- Distributed Power
- 5V to 3.3V Conversion
- 5V to 2.5V Conversion
- 5V to 1.8V Conversion
Documentation
Data Sheet 1
User Guide 2
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 |
|---|---|---|---|
| LT1959CR#PBF | 7-Lead DD Pak | ||
| LT1959CR#TRPBF | 7-Lead DD Pak | ||
| LT1959CS8#PBF | 8-Lead SOIC (Narrow 0.15 Inch) | ||
| LT1959CS8#TRPBF | 8-Lead SOIC (Narrow 0.15 Inch) | ||
| LT1959IR#PBF | 7-Lead DD Pak | ||
| LT1959IR#TRPBF | 7-Lead DD Pak | ||
| LT1959IS8#PBF | 8-Lead SOIC (Narrow 0.15 Inch) | ||
| LT1959IS8#TRPBF | 8-Lead SOIC (Narrow 0.15 Inch) |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
Aug 10, 2022 - 22_0175 Laser Top Mark Conversion for DDPAK & TO220 Packages Assembled in ADPG. Country of Origin Code [MY] To Be Incorporated On Top Mark |
||
| LT1959CR#PBF | PRODUCTION | |
| LT1959CR#TRPBF | PRODUCTION | |
| LT1959IR#PBF | PRODUCTION | |
| LT1959IR#TRPBF | PRODUCTION | |
|
Oct 24, 2024 - 24_0246 Migrating Bottom Trace Code Marking to Top Side Laser Marking for SOIC_N Package |
||
| LT1959CS8#PBF | PRODUCTION | |
| LT1959CS8#TRPBF | PRODUCTION | |
| LT1959IS8#PBF | PRODUCTION | |
| LT1959IS8#TRPBF | PRODUCTION | |
|
Oct 12, 2022 - 22_0255 Epoxy Change from Henkel 8290 to 8290A for 8-Lead SOIC Package (PCN part 2 of 2) |
||
| LT1959CS8#PBF | PRODUCTION | |
| LT1959CS8#TRPBF | PRODUCTION | |
| LT1959IS8#PBF | PRODUCTION | |
| LT1959IS8#TRPBF | PRODUCTION | |
|
Jun 16, 2021 - 21_0026 Laser Top Mark for 8SOICN Assembled in ADPG, UTL and CRM |
||
| LT1959CS8#PBF | PRODUCTION | |
| LT1959CS8#TRPBF | PRODUCTION | |
| LT1959IS8#PBF | PRODUCTION | |
| LT1959IS8#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
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Tools & Simulations
LTspice
Models for the following parts are available in LTspice:
- LT1959
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
LT1959CS8 | 4.5A Switch, 500kHz Step-Down Regulator, 5V to 15VIN, 1.8VOUT @ 4A
Resources
LT1959CS8 | 4.5A Switch, 500kHz Step-Down Regulator, 5V to 15VIN, 1.8VOUT @ 4A
Resources
LT1959CR | 4.5A Switch, 500kHz Step-Down Regulator, 5V to 15VIN, 1.8VOUT @ 4A
Resources
LT1959CR | 4.5A Switch, 500kHz Step-Down Regulator, 5V to 15VIN, 1.8VOUT @ 4A
Resources
Reference Designs
Part Used
