Overview
Features and Benefits
- Greatly Reduced Conducted and Radiated EMI
- Low Switching Harmonic Content
- Independent Control of Output Switch Voltage and Current Slew Rates
- Greatly Reduced Need for External Filters
- Single N-Channel MOSFET Driver
- 20kHz to 250kHz Oscillator Frequency
- Easily Synchronized to External Clock
- Regulates Positive and Negative Voltages
- Easier Layout Than with Conventional Switchers
Product Details
The LT1738 is a switching regulator controller designed to lower conducted and radiated electromagnetic interference (EMI). Ultralow noise and EMI are achieved by controlling the voltage and current slew rates of an external N-channel MOSFET switch. Current and voltage slew rates can be independently set to optimize harmonic content of the switching waveforms vs efficiency. The LT1738 can reduce high frequency harmonic power by as much as 40dB with only minor losses in efficiency.
The LT1738 utilizes a current mode architecture optimized for single switch topologies such as boost, flyback and Cuk. The IC includes gate drive and all necessary oscillator, control and protection circuitry. Unique error amp circuitry can regulate both positive and negative voltages. The internal oscillator may be synchronized to an external clock for more accurate placement of switching harmonics.
Protection features include gate drive lockout for low VIN, soft-start, output current limit, short-circuit current limit-ing, gate drive overvoltage clamp and input supply undervoltage lockout.
Applications
- Power Supplies for Noise Sensitive Communication Equipment
- EMI Compliant Offline Power Supplies
- Precision Instrumentation Systems
- Isolated Supplies for Industrial Automation
- Medical Instruments
- Data Acquisition Systems
Product Categories
Markets and Technologies
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
-
R303 Reliability Data3/23/2018
-
DC514A - Demo Manual9/24/2009
-
Two New Switching Regulators Deliver Both Power and Ultralow Noise9/1/2001 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.

Models for the following parts are available in LTspice:
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 |
---|---|---|---|---|
LT1738EG#PBF | Material Declaration | Reliability Data | 20-Lead SSOP | |
LT1738EG#TRPBF | Material Declaration | Reliability Data | 20-Lead SSOP | |
LT1738IG#PBF | Material Declaration | Reliability Data | 20-Lead SSOP | |
LT1738IG#TRPBF | Material Declaration | Reliability Data | 20-Lead SSOP | |
Wafer Fabrication Data | R303 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.