ST662AB ,DC-DC CONVERTER FROM 5V TO 12V, 0.03A FOR FLASH MEMORY PROGRAMMING SUPPLYAbsolute Maximum Ratings are those values beyond which damage to the device may occur. Functional o ..
ST662AB ,DC-DC CONVERTER FROM 5V TO 12V, 0.03A FOR FLASH MEMORY PROGRAMMING SUPPLYELECTRICAL CHARACTERISTICS (refer to the test circuits, V =4.5V to5.5V, T =T toCC A MINT ,unless ot ..
ST662AB ,DC-DC CONVERTER FROM 5V TO 12V, 0.03A FOR FLASH MEMORY PROGRAMMING SUPPLYST662ADC-DC CONVERTER FROM 5V TO 12V, 0.03AFOR FLASH MEMORY PROGRAMMING SUPPLY
ST662AB
DC-DC CONVERTER FROM 5V TO 12V, 0.03A FOR FLASH MEMORY PROGRAMMING SUPPLY
1/13April 2004 OUTPUT VOLTAGE: 12V± 5% SUPPLY VOLTAGE RANGE: 4.5V TO 5.5V GUARANTEED OUTPUT CURRENT UP TO
30mA VERY LOW QUIESCENT CURRENT: 100mA LOGIC CONTROLLED ELECTRONIC
SHUTDOWN: 1µA JUST CAPACITORS NEEDED (NO
INDUCTOR)
DESCRIPTIONThe ST662Aisa regulated charge pump DC-DC
converter.It provides 12V± 5% output voltageto
program byte-wide flash memory, and can supply
30mA output current from inputas lowas 4.75V. logic controlled shut down pin that interfaces
directly with microprocessor reduces the supply
currentto only 1µA.
ST662ADC-DC CONVERTER FROM 5V TO 12V, 0.03A
FOR FLASH MEMORY PROGRAMMING SUPPLY
TYPICAL APPLICATION CIRCUIT
ST662A2/13
ABSOLUTE MAXIMUM RATINGSAbsoluteMaximum Ratingsare those values beyond which damagetothe device may occur. Functional operation under theseconditionis
not implied.
THERMAL DATA
CONNECTION DIAGRAM (top view)
ORDERING CODES(*) AVAILABLEIN TAPE& REEL WITH "-TR" SUFFIX.
PIN DESCRIPTION
ST662A3/13
ELECTRICAL CHARACTERISTICS (referto the test circuits,VCC =4.5V to5.5V,TA =T MINto MAX ,unless otherwise specified. Typical Value are referredatTA= 25°C)
Figure1: Output Voltagevs Temperature
Figure2: Output Voltagevs Temperature
Figure3: Supply Currentvs Temperature
Figure4: Supply Currentvs Supply Voltage
ST662A4/13
Figure5: SHDN Pin Currentvs Temperature
Figure6: Output Voltagevs Shutdown Input
Voltage
Figure7: Output Voltagevs Shutdown Input
Voltage
Figure8: Output Voltagevs Shutdown Input
Voltage
Figure9: Test Circuit
ST662A5/13
DESCRIPTIONThe ST662isanIC developedto providea 12V regulated output 30mA from voltage inputas lowas 4.75
without any inductors.Itis usefulfora wide rangeof applications andits performances makesit ideal for
flash memory programming supply. evaluationkitis providedto facilitate the application. This includea single-side demo board designed
for surface-mount components.The operating principleof ST662 (see fig. 10)isto charge C1 and C2
capacitorby closing the S1 switch (while S2is opened)at theVCC voltage. AfterS1 willbe opened and S2
closedso that C1 and C2 capacitors are placedin series oneto each other, and both arein series with
VIN.The sumof VC1 and VC2 andVIis appliedto the capacitor C4. This works as voltage triple. An
amplifier error checks the output voltage and blocks the oscillatorif the output voltageis greater than 12V.
The shutdown pinis internally pulledtoVCC. Whenitis held low the output voltage risesto +12V. Fig.11
shows the transition timeof the shut down pin when theV SHDN goes from 5Vto 0V. Input logic levelsof
this input are CMOS compatible Applyinga logic highat this input, the VOUT oscillator willbe blocked and
the VOUT will reach theVI value by D1.In this condition ICC will be. lowas 1µA. The fig.12 shows the
transition timeof the shut down pin when theV SHDN goes from 0Vto 5V.
Figure10: Operating Principle Circuit
Figure11: Exiting Shutdown
Figure12: Entering Shutdown
NOTE: VCC =5V, IOUT=200µA NOTE: VCC=5V, IOUT=200µA
ST662A6/13
APPLICATION CIRCUITBasedon fast charge/dischargeof capacitors, this circuit involves high di/dt values limited onlyby RONof
switches. This impliesa critical layout design dueto the needto minimize inductive paths and place
capacitorsas closeas possibleto the device. good layout designis strongly recommended for noise reason. For best performance, use very short
connectionsto the capacitors and the values shownin table1. and C4 must have low ESRin orderto minimize the output ripple. Their values canbe reducedto2µF
and 1µF, respectively, when using ceramic capacitors, but must beof 10µFor largerif aluminium
electrolytic are chosen. must be placedas closeto the device as possible and could be omittedif very low output noise
performance are not required.
Fig13 and Fig14 show, respectively, our EVALUATIONkit layout and the relatively.
Figure13: KIT Lay-out
Figure14: Electrical Schematic
ST662A7/13
TABLE1: Listof Components
ST662A OUTPUT PERFORMANCE
Figure15: Output Voltagevs Output Current
Figure16: Efficiencyvs Output Current
Figure17: Load Transient Response
Figure18: Load Transient Response
NOTE: VCC=5V, IOUT=0to 30mA
NOTE: VCC=4.5to 5.5V, IOUT =30mA
