LTC3643 - 2A Bidirectional Power Backup Supply
- Bidirectional Synchronous Boost Capacitor Charger/Buck Regulator for System Backup
- Wide Input Voltage Range: 3V to 17V
- Up to 40V Capacitor Voltage Storage for High Energy Backup
- 2A Maximum CAP Charge Current
- Integrated Power N-Channel MOSFETs (150mΩ Top and 75mΩ Bottom)
- Integrated Power N-Channel MOSFET for Output/CAP Disconnect (50mΩ)
- Input Current Limit During Charging
- Fast 1MHz Switching Frequency
- ±1% Reference Accuracy for System Voltage Regulation
- Indicator Outputs for Charge Status and Input Power Fail
- Low Profile 24-lead 3mm × 5mm QFN Package
The LTC®3643 is a bidirectional synchronous step-up charger and step-down converter which efficiently charges a capacitor array up to 40V from an input supply between 3V to 17V. When the input supply falls below the programmable power-fail threshold, the step-up charger operates in reverse as a synchronous step-down regulator to power the system rail from the backup capacitor during this power interuption/failure condition.
When charging the backup capacitor, an external low-value sense resistor may be used to maintain an accurate current limit from the input supply or implement PowerPath™ functionality.
The step-down converter operates at a 1MHz switching frequency, allowing small external components to be used. Low quiescent current during regulation maximizes the energy usage from the backup capacitor.
CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprint compatible with Mentor Graphics PADS® v9.5 or later, and Cadence ORCAD® v16.5 or later.
For complete and up to date package information and drawings, please refer to our packaging page
- Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
- Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
- Please refer to our general ordering information or the product datasheet for more details
Package Variations and Pricing
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Demo BoardsLinear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.
|DC2220A||LTC3643 Demo Board | 2A, Bidirectional 40V Boost Charger/Buck Back-Up Power Regulator, 3V ≤ VIN ≤ 17V (Boost), Vout = 5V @ 2A/3A/4A (Buck)||$200.00|
- Backup Capacitor Systems
- Power Failure Backup Systems
- Solid-State Drives
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