LT1938
PRODUCTION25V, 2.2A, 2.8MHz Step-Down Switching Regulator
- Part Models
- 4
- 1ku List Price
- Starting From $4.20
Overview
- Wide Input Voltage Range: 3.6V to 25V
- 2.2A Maximum Output Current
- Adjustable Switching Frequency: 300kHz to 2.8MHz
- Low Shutdown Current: IQ < 1µA
- Integrated Boost Diode
- Power Good Flag
- Saturating Switch Design: 0.18Ω On-Resistance
- 1.265V Feedback Reference Voltage
- Output Voltage: 1.265V to 20V
- Soft-Start Capability
- Small 10-Pin Thermally Enhanced (3mm × 3mm) DFN Package
The LT1938 is an adjustable frequency (300kHz to 2.8MHz) monolithic buck switching regulator that accepts input voltages up to 25V. A high efficiency 0.18Ω switch is included on the die along with a boost Schottky diode and the necessary oscillator, control and logic circuitry. Current mode topology is used for fast transient response and good loop stability. The LT1938's high operating frequency allows the use of small, low cost inductors and ceramic capacitors resulting in low output ripple while keeping total solution size to a minimum. The low current shutdown mode reduces input supply current to less than 1µA while a resistor and capacitor on the RUN/SS pin provide a controlled output voltage ramp (soft-start). A power good flag signals when VOUT reaches 90% of the programmed output voltage. The LT1938 is available in a 3mm × 3mm DFN package with Exposed Pad for low thermal resistance.
Applications
- Automotive Battery Regulation
- Power for Portable Products
- Distributed Supply Regulation
- Industrial Supplies
- Wall Transformer Regulation
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 |
|---|---|---|---|
| LT1938EDD#PBF | 10-Lead DFN (3mm x 3mm w/ EP) | ||
| LT1938EDD#TRPBF | 10-Lead DFN (3mm x 3mm w/ EP) | ||
| LT1938IDD#PBF | 10-Lead DFN (3mm x 3mm w/ EP) | ||
| LT1938IDD#TRPBF | 10-Lead DFN (3mm x 3mm w/ EP) |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
Feb 14, 2025 - 25_0016 Bond Wire Change from Gold to Copper Wire (Notification Only) |
||
| LT1938EDD#PBF | PRODUCTION | |
| LT1938EDD#TRPBF | PRODUCTION | |
| LT1938IDD#PBF | PRODUCTION | |
| LT1938IDD#TRPBF | PRODUCTION | |
This is the most up-to-date revision of the Data Sheet.
Software Resources
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Request a Driver/SoftwareHardware Ecosystem
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Tools & Simulations
LTspice 1
Models for the following parts are available in LTspice:
- LT1938
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
LT1938EDD | 25V. 2.2A, 2.8MHz Step-Down Switching Regulator
Resources
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