LTC3736-1
Dual 2-Phase, No RSENSE™, Synchronous Controller with Spread Spectrum
Top
Overview
Features and Benefits
- Spread Spectrum Operation
- Tracking Function
- No Current Sense Resistors Required
- Out-of-Phase Controllers Reduce Required
- Input Capacitance
- Wide VIN Range: 2.75V to 9.8V
- Current Mode Operation
- 0.6V ±1.5% Voltage Reference
- Low Dropout Operation: 100% Duty Cycle
- Pulse Skipping Operation at Light Loads
- Internal Soft-Start Circuitry
- Power Good Output Voltage Monitor
- Output Overvoltage Protection
- Micropower Shutdown: IQ = 9µA
- Tiny Low Profile (4mm × 4mm) QFN and Narrow SSOP Packages
Product Details
The LTC3736-1 is a 2-phase dual synchronous stepdown switching regulator controller with tracking that drives external complementary power MOSFETs using few external components. The constant frequency current mode architecture with MOSFET VDS sensing eliminates the need for sense resistors and improves efficiency. Power loss and noise due to the ESR of the input capacitance are minimized by operating the two controllers out of phase.
A unique spread spectrum architecture randomly varies the LTC3736-1’s switching frequency from 450kHz to 580kHz, significantly reducing the peak radiated and conducted noise on both the input and output supplies, making it easier to comply with electromagnetic interference (EMI) standards.
Pulse skipping operation provides high efficiency at light loads. 100% duty cycle capability provides low dropout operation, extending operating time in battery-powered systems. The high switching frequencies allow for the use of small surface mount inductors and capacitors.
The LTC3736-1 is available in the low profile (0.75mm) 24-pin thermally enhanced (4mm × 4mm) QFN package and 24-lead narrow SSOP packages.
| Max Current Sense Voltage | Burst Mode | Soft Start | Spread Spectrum | |
| LTC3736 | 204mV | Yes | No | No |
| LTC3736-1 | 204mV | No | No | Yes |
| LTC3736-2 | 345mV | No | Yes | No |
Applications
- One or Two Lithium-Ion Powered Devices
- Notebook and Palmtop Computers, PDAs
- Portable Instruments
- Distributed DC Power Systems
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Documentation & Resources
-
R421 Reliability Data3/23/2018PDF66 K
-
DC803A - Demo Manual9/24/2009PDF423K
-
Dual Switcher with Spread Spectrum Reduces EMI11/1/2004 LT Journal
Tools & Simulations
LTspice
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.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.
Models for the following parts are available in LTspice:
LTC3736
LTC3736-1
LTC3736-2
Design Resources
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 Number | Material Declaration | Reliability Data | Pin/Package Drawing | CAD Symbols, Footprints & 3D Models |
|---|---|---|---|---|
| LTC3736EGN-1#PBF | Material Declaration | Reliability Data | 24-Lead SSOP (Narrow 0.15 Inch) | |
| LTC3736EGN-1#TRPBF | Material Declaration | Reliability Data | 24-Lead SSOP (Narrow 0.15 Inch) | |
| LTC3736EUF-1#PBF | Material Declaration | Reliability Data | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | |
| LTC3736EUF-1#TRPBF | Material Declaration | Reliability Data | 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP) | |
| Wafer Fabrication Data | R421 Reliability Data |
PCN-PDN Information
Select a model from the dropdown below to subscribe to PCN/PDN notifications and view past notifications as well.
Support & Discussions
Sample & Buy
Ordering FAQs
See our Ordering FAQs for answers to questions about online orders, payment options and more.
Buy Now Pricing
(**) Displayed Buy Now Price and Price Range is based on small quantity orders.
List Pricing
(*)The 1Ku 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. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
Lead Times
Please see the latest communication from our CCO regarding lead times.
Sampling
Selecting the Sample button above will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.
Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.