LM2630MTC-ADJ ,Synchronous Step-Down Voltage Regulator [Not recommended for new designs]Applicationstures include the external synchronization pin, and then Notebook and subnotebook compu ..
LM2631MTC-ADJ ,Synchronous Step-Down Voltage Regulator [Not recommended for new designs]Electrical Characteristics=Specifications in standard type face are for T 25˚C and those with boldf ..
LM2631MTCX-ADJ ,Synchronous Step-Down Voltage Regulator [Not recommended for new designs]Featuresn 4.5V to 30V input rangeThe LM2631 controller provides all the active functions forstep-do ..
LM2633MTD ,Advanced Two-Phase Synchronous Triple Regulator Controller for Notebook CPUsfeatures an Inteln Tiny TSSOP packagemobile CPU compatible precision 5-bit digital-to-analog con-SW ..
LM2633MTDX ,Advanced Two-Phase Synchronous Triple Regulator Controller for Notebook CPUsPin DescriptionsVDD2 (Pin 32): The supply rail for Channel 2 bottom gateFB1 (Pin 1):The feedback in ..
LM2635 ,Synchronous Buck Regulator ControllerPin Descriptionsabled when this pin is pulled low. It is internally pulled up toV via a 90 μA curre ..
LM4898LDX ,1 Watt Fully Differential Audio Power Amplifier With Shutdown Selectfeatures a low-power consumption shutdownn Improved pop & click circuitry eliminates noises duringm ..
LM4898MMX ,1 Watt Fully Differential Audio Power Amplifier With Shutdown SelectGeneral Description Key SpecificationsThe LM4898 is a fully differential audio power amplifierj Imp ..
LM4899LD ,1 Watt Fully Differential Audio Power Amplifier With Shutdown Select and Fixed 6dB Gainfeatures a low-power consumption shutdownn Can drive capacitive loads up to 500pFmode. To facilitat ..
LM4900M ,265mW at 3.3V Supply Audio Power Amplifier with Shutdown ModeGeneral Description THD+N at 1kHz for 675mW continuousaverage output power into 8Ω,The LM4900 is a ..
LM4900MM ,265mW at 3.3V Supply Audio Power Amplifier with Shutdown ModeFeaturesage while requiring a minimal amount of external compo-nents. Since the LM4900 does not req ..
LM4900MMX ,265mW at 3.3V Supply Audio Power Amplifier with Shutdown Modefeatures an externally controlled, low powern Thermal shutdown protection circuitryconsumptionshutd ..
LM2630MTC-ADJ
Synchronous Step-Down Voltage Regulator [Not recommended for new designs]
LM2630
Synchronous Step-Down Power Supply Controller
General DescriptionThe LM2630 controller providesallthe active functionsfor
step-down (buck) switching converters. These dc-to-dc con-
verters provide core CPU powerin battery-operated sys-
tems.
High efficiencyis achievedby using synchronous rectifica-
tionand pulse-skipping mode operationat light load. Inex-
pensive N-channel MOSFETsare usedto reduce system
cost. Bootstrap circuitis usedto drive the high-side
N-channel MOSFET.
Currentmode controlschemeis usedto improve lineregula-
tion and transient response, also provides cycle-by-cycle
current limiting.
The operating frequencyis adjustable between 200kHzand
400 kHz.An external shutdownpincanbe usedto disable
the deviceand reducethe quiescentcurrent to0.1μA.Inlow
noise applications,bringing theFPWMpinhighcan forcethe
deviceto operatein constant frequency mode. Other fea-
tures includethe external synchronization pin, andthe
PGOODpinto indicatethe stateofthe output voltage.
Protection circuitry includes thermal shutdown, undervoltage
shutdown, soft-start capability,andtwo levelsof currentlim-
its:Thefirst level simplylimitsthe loadcurrent directly; atthe
second level,ifthe load pullsthe output voltage down below
80%ofthe regulated value,the chip willshut down. This
latched operationis disabled during startup,butan internal
timerwill enableitifthe output doesnot comeupinthepre-
set time.
Features 4.5Vto 30V input range Adjustable output (1.8Vto6V) 200 kHzto400kHz adjustable operating frequency Externally synchronizable On-board power good function Precision 1.24V reference output0.8mA typical quiescent current0.1μA shutdown current Thermal shutdown Direct current limit protection Input undervoltage lockout Output Undervoltage shutdown protection Programmable soft-start function Tiny TSSOP package
Applications Notebookand subnotebook computers Cellular phones Portable instruments Battery-powered digital devices
Typical Application CircuitDS100120-1
February 1999
LM2630
Synchronous
Step-Down
Power
Supply
Controller 1999 National Semiconductor Corporation DS100120
