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Overview
Features and Benefits
- Silent Switcher® Architecture
- Ultralow EMI Emissions
- Optional Spread Spectrum Modulation
- High Efficiency at High Frequency
- Up to 96% Efficiency at 1MHz, 12VIN to 5VOUT
- Up to 95% Efficiency at 2MHz, 12VIN to 5VOUT
- Wide Input Voltage Range: 3.4V to 42V
- 6A Maximum Continuous, 7A Peak Output
- External Compensation: Fast Transient Response and Current Sharing (LT8643S-2)
- Fast Minimum Switch On-Time: 30ns
- Ultralow Quiescent Current Burst Mode® Operation
- 2.5μA IQ Regulating 12VIN to 3.3VOUT (LT8640S-2)
- Output Ripple < 10mVP-P
- Low Dropout Under All Conditions: 100mV at 1A
- Forced Continuous Mode
- Adjustable and Synchronizable: 200kHz to 3MHz
- Output Soft-Start and Tracking
- Small 24-Lead 4mm × 4mm LQFN Package
- AEC-Q100 Qualified for Automotive Applications
Product Details
The LT8640S-2/LT8643S-2 synchronous step-down regulator features Silent Switcher architecture designed to minimize EMI emissions while delivering high efficiency at high switching frequencies. Peak current mode control with a 30ns minimum on-time allows high step-down ratios even at high switching frequencies. The LT8643S-2 has external compensation to enable current sharing and fast transient response at high switching frequencies.
Burst Mode operation enables ultralow standby current consumption, forced continuous mode can control frequency harmonics across the entire output load range, or spread spectrum operation can further reduce EMI emissions.
APPLICATIONS
- Automotive and Industrial Supplies
- General Purpose Step-Down
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
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Silent Switcher Technology8/15/2023
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