LTC3618
RECOMMENDED FOR NEW DESIGNSDual 4MHz, ±3A Synchronous Buck Converter for DDR Termination
- Part Models
- 10
- 1ku List Price
- Starting From $6.21
Overview
- DDR Power Supply, Termination and Reference
- High Efficiency: Up to 94%
- Dual Outputs with ±3A Output Current Capability
- 2.25V to 5.5V Input Voltage Range
- ±1% Output Voltage Accuracy
- VTT Output Voltage Down to 0.5V
- Shutdown Current ≤1μA
- VTTR = VDDQIN/2, VFB2 = VTTR
- Adjustable Switching Frequency Up to 4MHz
- Internal or External Compensation
- Selectable 0°/90°/180° Phase Shift Between Channels
- Internal or External Soft-Start for VDDQ, Internal Soft-Start for VTT
- Power Good Status Outputs
- Low Profile 4mm × 4mm QFN-24 and TSSOP-24 Packages
- AEC-Q100 Qualified for Automotive Applications
The LTC3618 is a dual synchronous step-down regulator using a current mode, constant-frequency architecture. It provides a complete DDR solution with an input voltage range from 2.25V to 5.5V.
The output of the first step-down regulator offers a high accuracy VDDQ supply. A buffered reference generates VTTR at 50% of VDDQIN and drives loads up to ±10mA. The second regulator generates the DDR termination voltage (VTT) equal to VTTR. Both regulators are capable of delivering ±3A of load current at 1MHz switching frequency.
The operating frequency is externally programmable up to 4MHz, allowing the use of small surface mount inductors. 0°, 90°, or 180° of phase shift between the two channels can be selected to minimize input current ripple. For switching noise-sensitive applications, the LTC3618 can be synchronized to an external clock up to 4MHz.
The LTC3618 is offered in leadless 24-pin 4mm × 4mm QFN and thermally enhanced 24-pin TSSOP packages.
APPLICATIONS
- DDR Memory
- Supports DDR, DDR2, and DDR3 Standards
- Tracking Supplies
Documentation
Data Sheet 1
User Guide 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 |
|---|---|---|---|
| LTC3618EFE#PBF | 24-Lead TSSOP w/ EP | ||
| LTC3618EFE#TRPBF | 24-Lead TSSOP w/ EP | ||
| LTC3618EUF#PBF | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LTC3618EUF#TRPBF | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LTC3618IFE#PBF | 24-Lead TSSOP w/ EP | ||
| LTC3618IFE#TRPBF | 24-Lead TSSOP w/ EP | ||
| LTC3618IUF#PBF | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LTC3618IUF#TRPBF | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LTC3618IUF#WPBF | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | ||
| LTC3618IUF#WTRPBF | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
May 18, 2026 - 26_0072 Epoxy Change for Select TSSOP Products |
||
| LTC3618EFE#PBF | PRODUCTION | |
| LTC3618EFE#TRPBF | PRODUCTION | |
| LTC3618IFE#PBF | PRODUCTION | |
| LTC3618IFE#TRPBF | PRODUCTION | |
|
Feb 14, 2025 - 25_0017 Bond Wire Change from Gold to Copper |
||
| LTC3618EFE#PBF | PRODUCTION | |
| LTC3618EFE#TRPBF | PRODUCTION | |
|
Apr 6, 2022 - 22_0068 Laser Top Mark for ETSSOP and TSSOP Packages Assembled in ADPG [PNG] and UTL |
||
| LTC3618EFE#PBF | PRODUCTION | |
| LTC3618EFE#TRPBF | PRODUCTION | |
| LTC3618IFE#PBF | PRODUCTION | |
| LTC3618IFE#TRPBF | PRODUCTION | |
|
Apr 14, 2025 - 25_0017 Bond Wire Change from Gold to Copper |
||
| LTC3618EUF#PBF | PRODUCTION | |
| LTC3618EUF#TRPBF | PRODUCTION | |
| LTC3618IFE#PBF | PRODUCTION | |
| LTC3618IFE#TRPBF | PRODUCTION | |
| LTC3618IUF#WPBF | PRODUCTION | |
| LTC3618IUF#WTRPBF | PRODUCTION | |
|
Apr 17, 2025 - 25_0043 Change of Gold to Copper Wire and BOM (Automotive) |
||
| LTC3618IUF#WPBF | PRODUCTION | |
| LTC3618IUF#WTRPBF | 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 1
Models for the following parts are available in LTspice:
- LTC3618
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.