Features and Benefits
- Dual Outputs Each with 2A Output Current
- High Efficiency: 19mΩ NMOS and 75mΩ PMOS
- Wide Bandwidth, Fast Transient Response
- Switching Frequency Synchronizable Up to 3MHz
- VIN Range: 2.25V to 5.5V
- VOUT Range: 0.5V to VIN
- VOUT Accuracy: ±1%
- Low Ripple Burst Mode® Operation
- Peak Current Mode Control
- Minimum On-Time: 25ns
- Safely Tolerates Inductor Saturation in Overload
- Shutdown Current: 1.2µA
- Precision 400mV Enable Thresholds
- Internal Soft-Start and Compensation
- Power Good Output
- Low Profile, Thermally Enhanced 12-Lead 2mm × 2mm × 0.74mm LQFN Package
- AEC-Q100 Qualified for Automotive Applications
The LTC3315A features dual 2A monolithic synchronous step-down converters operating from a 2.25V to 5.5V input supply in one package for space-constrained applications with demanding performance requirements. Using constant frequency, peak current mode control at switching frequencies up to 3MHz with a minimum on-time as low as 25ns, both bucks achieve high efficiency and fast transient response in a very small application footprint.
The LTC3315A operates in forced continuous or pulse skip mode for low noise or in Burst Mode® operation for high efficiency at light loads. The common buck switching frequency is 2MHz and can be synchronized to an external oscillator via the MODE/SYNC pin.
The LTC3315A can regulate outputs as low as 500mV. Other features include precision enable thresholds, a PGOOD signal, output overvoltage protection, thermal shutdown, output short-circuit protection, and up to 100% duty cycle operation for low dropout. The LTC3315A is available in a compact 2mm × 2mm LQFN package.
- Servers, Telecom Supplies, Optical Networking
- Distributed DC Power Systems (POL)
- FPGA, ASIC, µP Core Supplies
Product Lifecycle Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (1)
Demonstration Circuit DC2747A features the LTC3315A dual 5V, 2A Synchronous Step-Down DC/DC regulators operating at 2.0MHz. One regulator provides a 1.2V output and the other provides 1.8V, both up to a 2A load. The LTC3315A supports adjustable output voltages from 0.5V to VIN, operating frequencies from 1MHz up to 3MHz. The LTC3315A is a compact, high efficiency, and high speed synchronous monolithic step-down switching regulator. Fast minimum on-time of 25ns enables high VIN to low VOUT conversion at high frequency.
The DC2747A operating mode may be selected as Burst Mode operation, Skip mode or Forced Continuous (FC) mode. Setting JP1 to the FC/SYNC position will allow the LTC3315A to sync to a clock frequency from 1MHz to 3MHz. The LTC3315A operates in Forced Continuous mode when syncing to an external clock.
The LTC3315A data sheet gives a complete description of the device, operation and application information. The data sheet must be read in conjunction with this demo. The LTC3315A is assembled in a 2mm × 2mm LQFN package with exposed pads for low thermal resistance. The PCB Considerations section in the data sheet.
The Efficiency vs Load graph shows the efficiency and the power loss of the circuit with a 3.3V input in Burst Mode operation.
Tools & Simulations
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.
Models for the following parts are available in LTspice:
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
Design tools for the following parts are available in LTpowerCAD:
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.
Sample & Buy
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 Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.