FEATURES

*Wide Vin Range: 4V to 32V

*+0.67% 0.6V Reference Voltage

*Output Voltage Tracking Capability

*Programmable Margining

*Sense Resistor Optional

**True Current Mode Control

*2% to 90% Duty Cycle at 200kHz

*tON(MIN)S 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: lo < 30μA

*Power Good Output Voltage Monitor

Tracks the Reference Input Pin

*Available in (5mm x 5mm) QFN and 28-Lead SSOP Packages

DESCRIPTION

The ZC3770 is a synchronous step-down switchingregulatorcontrollerwithoutputvoltageup/downtracking capability and voltage margining. ltsadvanced functions and high accuracy referenceare ideal for powering high performance server,ASlC and computer memory systems.

The ZC3770 uses a constant on-time,

valleycurrentmodecontrolarchitecturetodeliververylowdutyfactors withoutrequiringasenseresistor.Theoperatingfrequencyisselectedbyanexternalresistorandiscompensatedforvariationsininputsupplyvoltage.Aninternalphase-locked loop allows the lC to besynchronized to an external clock.

Faultprotectionisprovidedbyanovervoltagecomparator and input undervoltage lockout. The regulatorcurrent limit is user programmable. A wide supplyrange allows voltages as high as 32V to be steppeddown to as low as a0.6Voutput.Powersupplysequencingisaccomplished using anexternal soft-start timing capacitor.

APPLICATIONS

*Distributed Power Systems

*Server Power Supply

合作洽谈/样品申请：402572194（QQ）

邮箱：gaomaobing@zcc-china.net