Overview
Features and Benefits
- Silent Switcher® Architecture
- Ultralow EMI Emissions
- Optional Spread Spectrum Modulation
- Up to 95% Efficiency at 1MHz, 12VIN to 5VOUT
- Up to 94% Efficiency at 2MHz, 12VIN to 5VOUT
- Wide Input Voltage Range: 3.4V to 65V
- Ultralow Quiescent Current Burst Mode Operation
- 2.5μA IQ Regulating 12VIN to 3.3VOUT
- Output Ripple < 10mVP-P
- Fast Minimum Switch On-Time: 40ns
- Low Dropout Under All Conditions: 60mV at 1A
- Adjustable and Synchronizable: 200kHz to 2.2MHz
- Peak Current Mode Operation
- Output Soft-Start and Tracking
- Small 32-Lead 6mm × 4mm LQFN Package
- AEC-Q100 Qualification In Progress
Product Details
The LT8645S-2 synchronous step-down regulator features Silent Switcher architecture designed to minimize EMI emissions while delivering high efficiency at high switching frequencies. This performance makes the LT8645S-2 ideal for noise sensitive applications and environments.
The fast, clean, low-overshoot switching edges enable high efficiency operation even at high switching frequencies, leading to a small overall solution size. Peak current mode control with a 40ns minimum on-time allows high step-down ratios even at high switching frequencies.
Burst Mode® operation enables ultralow standby current consumption, pulse-skipping mode allows full switching frequency at lower output loads, or spread spectrum operation can further reduce EMI emissions.
Applications
- Automotive and Industrial Supplies
- General Purpose Step-Down
- GSM Power 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.
Documentation & Resources
Tools & Simulations
LTpowerCAD
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:
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 |
---|---|---|---|---|
LT8645SEV-2#PBF | Material Declaration | Reliability Data | 32-Lead LQFN (6mm x 4mm x 0.94mm w/ EP) | |
LT8645SEV-2#WPBF | Material Declaration | Reliability Data | 32-Lead LQFN (6mm x 4mm x 0.94mm w/ EP) | |
LT8645SHV-2#PBF | Material Declaration | Reliability Data | 32-Lead LQFN (6mm x 4mm x 0.94mm w/ EP) | |
LT8645SHV-2#WPBF | Material Declaration | Reliability Data | 32-Lead LQFN (6mm x 4mm x 0.94mm w/ EP) | |
LT8645SJV-2#PBF | Material Declaration | Reliability Data | 32-Lead LQFN (6mm x 4mm x 0.94mm w/ EP) | |
LT8645SJV-2#WPBF | Material Declaration | Reliability Data | 32-Lead LQFN (6mm x 4mm x 0.94mm w/ EP) | |
Wafer Fabrication Data |
Sample & Buy
Ordering FAQs
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Buy Now Pricing
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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
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