FERTURES
Wide VIN Range:4.5V to 36V
■±0.67%,0.6V Reference Voltage
■Output Voltage Tracking Capability
■True Remote Sensing Differential Amplifier
■Sense Resistor Optional
■True Current Mode Control
■2% to 90% Duty Cycle at 200kHz
■tO(MIN)<100ns aPhase-Locked Loop Frequency Synchronization Powerful Dual N-Channel MOSFET Driver
■Adjustable Cycle-by-Cycle Current Limit Adjustable Switching Frequency
■Programmable Soft-Start aCurrent Foldback Protection(Disabled at Start-Up)
■Output Overvoltage Protection
■Micropower Shutdown:30uA
■Power Good Output Voltage Monitor Tracks the Reference Input Pin Available in (5mm× 5mm)32-Lead QFN and 28-Lead SSOP Narrow Packages
APPLICATIOnS
*Distributed Power Systems
*Server Power Supplies
DESCRIPTIOn
The LTC@3823 is a synchronous step-down switching regu-lator controller with true remote differential output sensing andoutputvoltage up/downtracking capability. Its advanced functions andhighaccuracy referenceare ideal for powering high performance server, ASIC and computer memory systems.
The LTC3823IUH uses a constant on-time, valley current mode control architecture to deliver very low duty fac-tors without requiring a sense resistor. The operating frequency is selected by an external resistor and is com-pensated for variations in input supply voltage. An internal phase-locked loop allows the IC to be synchronized to an external clock.
Fault protection is provided by an overvoltage compara-tor and input undervoltage lockout. The regulator current limit is user programmable.A wide supply range allows voltages as high as 36V to be stepped down to as low as a 0.6V output. When using remote sense, output voltages up to 3.3V can be developed, and up to 90% of Viy without remote sense. Power supply sequencing is accomplished using an external soft-start timing capacitor.
Feature
- Wide VIN Range: 4.5V to 36V
- ±0.67%, 0.6V Reference Voltage
- Output Voltage Tracking Capability
- True Remote Sensing Differential Amplifier
- Sense Resistor Optional
- True Current Mode Control
- 2% to 90% Duty Cycle at 200kHz
- tON(MIN) < 100ns
- Phase-Locked Loop Frequency Synchronization
- Powerful Dual N-Channel MOSFET Driver
- Adjustable Cycle-by-Cycle Current Limit
- Adjustable Switching Frequency
- Programmable Soft-Start
- Current Foldback Protection (Disabled at Start-Up)
- Output Overvoltage Protection
- Micropower Shutdown: 30μA
- Power Good Output Voltage Monitor Tracks the Reference Input Pin
- Available in (5mm × 5mm) 32-Lead QFN and 28-Lead SSOP Narrow Packages
Applications
- Distributed Power Systems
- Server Power Supplies
(Picture: Pinout)
