DC-DC Converter Control Circuits

Transcription

1 MC0A OUTPUT WITCH CUENT IN EXCE OF.A % EFEENCE ACCUACY LOW UIECENT CUENT:.mA(TYP.) OPEATING FOM TO 0 EUENCY OPEATION TO 00KHz ACTIE CUENT LIMITING DECIPTION The MC0A series is a monolithic control circuit delivering the main functions for DCDC voltage converting. The device contains an intermal temperature compensated reference,, duty cycle controlled oscillator with an active current limit circuit driver and high current output switch. Output voltage is adjustable through two external resistors with a % reference accuracy. Employing a minimum number of external components the MC0A devices series is designed for tepdown, tepup and oltagelnverting applications. OP/ DIP PIN Configulation witch Collector witch Emitter Timing Capacitor Ground ODEING INFOMATION Device Package MC0AD OP MC0AN DIP Drive Collector Ipk ense cc Comparator Input BLOCK DIAGAM Drive Collector s witch Collector Ipk ense witch Emitter Timing Capacitor cc Comparator Comparator lnverting input. eference egulator GND

2 MC0A ABOLUTE MAXIMUM ATING YMBOL cc ir WC WE CE dc I dc I sw P tot T op T stg PAAMETE ALUE UNIT Power upply oltage Comparator input oltage ange witch Collector oltage witch Emitter oltage (WC=0) witch Collector to Emitter oltage Driver Collector oltage Driver Collector Current witch Current Power Dissipation at T amb = (for Plastic Package ) (for OIC Package ) Operating Ambient Temperature ange 0 0. to to 0 ma A W torage Temperature ange 0 to 0 Absolute Maximum ating are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. THEMAL DATA YMBOL thiamb PAAMETE DIP O UNIT 00 0 /w Thermal esistance Junctionambient ( * ) Max ( * ) This alue depends from thermal design of PCB on which the device is mounted. CONNECTION DIAGAM (top view) PIN CONNECTION WC WE TC GND PIN NO YMBOL NAME AND FUNCTION WC witch Collector DC WE witch Emitter IPK TC Timing Capactor GND Ground CC CII Comparator lnverting lnput CII cc oltage upply C00 I PK I PK ense DC oltage Driver Collector

3 MC0A ELECTICAL CHAACTEITIC( efer to the test circuits, CC =, T a =T LOW to T HIGH, unless otherwise specified, see note ) OCILLATO YMBOL PAAMETE TET CONDITION MIN. TYP. MAX. UNIT F OC Frequency pin = 0,C T = nf,t a = o C KHz I chg Charge Current CC = to 0,T a = o C μa I dischg Discharge Current CC = to 0,T a = o C μa I dischg /I chg Discharge to Charge Current atio Pin = CC,T a = o C... ipk(sense) Current Limit ense oltage I chg = I dischg,t a = o C m OUTPUT WITCH YMBOL PAAMETE TET CONDITION MIN. TYP. MAX. UNIT CE(sat) aturation oltage, I W = A,Pins, connected. CE(sat) Darlington connection aturation oltage I W = A, pin = Ω to CC, Forced β ~ h FE DC Current Gain I W = A, CE =, T a = o C 0 0 Collector Offtate Current CE = μa I C(off) COMPAATO YMBOL PAAMETE TET CONDITION MIN. TYP. MAX. UNIT th Threshold oltage T a = o C T a = T LOW to T HIGH eg line Threshold oltage Line egulation CC = to 0 m I IB Input Bias Current IN = 0 00 na TOTAL DEICE YMBOL PAAMETE TET CONDITION MIN. TYP. MAX. UNIT I CC upply Current CC = to 0, C T =nf Pin= CC, pin > th, Pin=GND emaining pins open for MC0A. ma TATUP tartup oltage(note ) T a = o C,C T =μf,pin= 0 for MC0A. Notes: ) Maximum package power dissipation limit must be observed. ) T LOW = 0 o C, T HIGH = 0 o C ) If Darlington configuration is not used, care must be taken to avoid deep saturation of output switch. The resulting switchoff time may be adversely affected. In a Darlington configuration the following output driver condition is suggested: Forced β of output current switch= I COUTPUT /(I CDIE ma * ) 0 * Current less due to a built in KΩ antileakage resistor. ) tartup oltage is the minimum Power upply oltage at which the internal oscillator begains to work.

4 MC0A TYPICAL ELECTICAL CHAACTEITIC Emitter Follower Configuration Output aturation oltage vs Emitter Current CE (sat) () CC = Pin,,= CC Pins,=GND T a = Output witch ONOFF Time vs Oscillator Timing Capacitor T on T off ( μs ) CC = Pin= CC Pin=GND T a = T on.0. 0 T off I E ( ma ) C T ( nf ) Common Emitter Configuration Output witch aturation oltage vs Collector Current CE (sat) ().0 Darlington Connection Darlington Configuration Collector Emitter aturation oltage ( CE(sat) ) vs Temperature CE (sat) ( m ) CC = Pin= CC Pins,,=GND T a = CC = I C =A 0. Forced β = C ( ma ) T J ( ) Power Collector Emitter sturation oltage Current Limit ense oltage oltage ( ipk ) vs ( CE(sat) ) vs Temperature Temperature CE (sat) ( m ) 00 0 CC = I C =A ipk ( m ) 0 0 MC0A CC = I chg =I dischg T J ( ) T J ( )

5 MC0A TYPICAL ELECTICAL CHAACTEITIC (Continued) eference oltage vs Temperature Bias Current vs Temperature ref () I Bias ( na )..0 CC = 0 CC = C II to GND T J ( ) upply Current vs Temperature T J ( ) upply Current vs Input oltage I CC ( ma ) I CC ( ma ) CC = C T = nf.0..0 T J = C T = nf T J ( ) in ()

6 MC0A TYPICAL APPLICATION CICUIT tepup Converter L 0Ω sc 0.Ω DC WC Ipk WE cc TC IN CII GND C C.nF /ma 00 μf 0μH MC0A D BY00.KΩ KΩ C 0μF tepdown Converter DC WC Ipk WE cc TC IN CII GND sc 0.Ω C 00 μf MC0A C 0pF BY00 D L 0μH.KΩ.KΩ C /0.A 0 μf

7 MC0A tepup With External NPN witch sc IN. eference egulator oltage Inverting Converter DC WC Ipk WE cc TC IN CII GND. to 0.Ω C 00 μf MC0A C.nF L 90μH D BY00.KΩ 9Ω C 000μF /00 ma

8 MC0A tepdown With External NPN witch sc IN. eference egulator tepdown With External PNP witch sc IN. eference egulator

9 MC0A oltage Inverting With External NPN witch sc IN. eference egulator oltage Inverting With External PNP aturated witch sc IN. eference egulator 9

10 MC0A Dual Output oltage GND sc IN. eference egulator Higher Output Power, Higher Input oltage Isolated from input IN sc. eference egulator 0