IP35063 IP33063 IP34063 DC–DC CONVERTER CONTROL CIRCUIT TOP VIEW SW ITCH COLLECTOR 1 8 D RIVER C OLLEC TO R SW ITCH EMITTER 2 7 Ipk SENSE TIM ING C APACITOR 3 6 VC C GND 4 5 C OMP AR ATOR INVER TIN G INPUT FEATURES J Package – 8 Pin Ceramic DIP N Package – 8 Pin Plastic DIP D-8 Package – 8 Pin Plastic (150) SOIC • • • • • • • Operation from 2.5 to 40V input Low Standby Current Current Limiting Output switch current of 1.5A Output voltage adjustable from 1.25 to 40V Operating frequency from 100Hz to 100kHz Direct replacement for MC34063/MC34063A series Order Information Part Number IP35063 IP33063 IP34063 J–Pack 8 Pin ✔ ✔ ✔ N–Pack 8 Pin D–8 8 Pin ✔ ✔ ✔ ✔ Temp. Range -55 to +125°C -40 to +85°C 0 to +70°C Note: To order, add the package identifier to the part number. eg. IP35063D–8 ABSOLUTE MAXIMUM RATINGS +40V Power Supply Voltage –0.3V to +40V Comparator Input Voltage Range Switch Collector Voltage 40V Switch Emitter Voltage 40V Switch Collector to Emitter Voltage 40V Driver Collector Voltage 40V Switch Current 1.5A Power Dissipation @ Tamb = 25°C Ceramic Packages Plastic Packages 10mW/°C Derate above 25°C Operating Junction Temperature Ceramic Packages Plastic Packages Operating Ambient Temperature Range See Table Above Storage Temperature Range Semelab plc. 1.25W 1W Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. 150°C 125°C See Table Above –65 to 150°C Prelim. 2/95 IP35063 IP33063 IP34063 DESCRIPTION Driver Collector The IP34063 series of control circuits contains all the functions required to implement DC–DC converters. Included are internal voltage reference, comparator, controlled duty cycle oscillator with current limit circuit, driver, and high current output switch. This series was specifically designed to be incorporated in Step-Down (Buck) and Step-Up (Boost) applications with a minimum number of external components. 8 1 S Q Q2 Q1 R 170 Ω 7 Switch Collector 2 Ipk Sense Switch Emitter OSCILLATOR 6 3 V CC Timing Capacitor COMPARATOR 1.25 V REFERENCE REGULATOR Comparator Inverting Input ELECTRICAL CHARACTERISTICS Parameter 5 4 Gnd (Test Parameters unless otherwise stated : VCC = 5V , TJ = 25°C) Test Conditions Min. Typ. Max. Units OSCILLATOR Charging Current VCC = 5 to 40V 20 35 50 µA Discharge Current VCC = 5 to 40V 150 200 250 µA Voltage Swing Discharge to Charge Current Ratio Ipk(sense) = VCC Current Limit Sense Voltage Ichg = Idischg 250 0.5 Vpp 6.0 — 300 350 mV 1 1.3 V 0.45 0.7 V OUTPUT SWITCH Saturation Voltage, Darlington Connection * ISW = 1.0A Saturation Voltage * ISW = 1.0A IC(Driver) = 50mA (Forced β = 20) DC Current Gain ISW = 1.0A , VCE = 5.0V Collector Off–State Current VCE = 40V 35 120 — 10 nA COMPARATOR Threshold Voltage * 1.18 Threshold Voltage Line Regulation * VCC = 3 to 40V Input Bias Current * VIN = 0V 1.25 1.32 V 0.04 0.2 mV/V 40 400 nA 2.4 3.5 mA TOTAL DEVICE Supply Current * VCC = 5 to 40V CT = 0.001µF Ipk(sense) = VCC VPIN 5 > Vth Pin 2 = Gnd , Remaining Pins Open. NOTES * Applies over full operating temperature range (see order information). Semelab plc. Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Prelim. 2/95 IP35063 IP33063 IP34063 DESIGN FORMULA TABLE Calculation tON Step–Down VOUT + VF Step–Up VOUT + VF - VIN(MIN) tOFF VIN(MAX) - VSAT - VOUT VIN(MIN) - VSAT 1 1 fMIN fMIN (tON + tOFF)MAX CT 10-5 4x tON Ipk(switch) 2 IOUT(MAX) RSC 0.33 / Ipk(switch) L(MIN) CO VIN(MAX) - VSAT - VOUT Ipk(switch) 4 x 10-5 tON 2 IOUT(MAX) tON(MAX) tON + tOFF tOFF 0.33 / Ipk(switch) VIN(MIN) - VSAT Ipk(switch) tON(MAX) Ipk(switch) (tON + tOFF) IOUT tON 8 Vripple(p–p) Vripple KEY VSAT VF — Saturation voltage of the output switch. — Forward voltage drop of the ringback rectifier. The following power supply characteristics must be chosen:– VIN VOUT IOUT fMIN Vripple(p–p) — Nominal input voltage. If this voltage is not constant, then use VIN(MAX) for step–down and VIN(Min) for step–up converter. R2 — Desired output voltage, VOUT = 1.25 1 + . R1 — Desired output current. — Minimum desired output switching frequency at the selected values for VIN and IO. — Desired peak–to–peak output ripple voltage. In practice, the calculated value will need to be increased due to the capacitors equivalent series resistance and board layout. The ripple voltage should be kept to a low value since it will directly affect the line and load regulation. Semelab plc. ( ) Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. Prelim. 2/95 IP35063 IP33063 IP34063 APPLICATIONS INFORMATION Step–Down Converter Step–Up Converter L 170 µH 8 1 8 1 1 8 0Ω S Q S Q2 Q1 R Q2 Q1 R 170 Ω 7 Q 2 170 Ω 7 Ipk 2 1N5819 Ip k 1N5822 OSCILLATOR R SC 0.33 Ω 6 V IN 25V CT OSCILLATOR R SC 0.22 Ω 3 V CC 1.25 V REFERENCE REGULATOR 100 µF 3 V CC COMPARATOR 1.25 V REFERENCE REGULATOR 100 µF CT 470pF 5 6 V IN 12V L 220 µH COMPARATOR CT 4 CT 1 50 0p F 5 4 V OUT V OUT 5.0V 500mA R2 3.3K R1 1.2K CO 470 µF 28V 175 mA R2 47K R1 2 .2 K CO 1500 µF External Current Boost Connections for IC > 1.5A Step–Down, External NPN Switch 8 Step–Up, External NPN Switch 1 S 8 S Q1 R 2 Q1 170 Ω 7 V OUT OSCILLATOR V OUT Q2 Q R 170 Ω 7 2 OSCILLATOR R SC R SC 6 V IN 1 Q2 Q 3 6 V IN COMPARATOR 3 COMPARATOR 1.25 V REFERENCE REGULATOR 1.25 V REFERENCE REGULATOR 5 4 5 Step–Down, External PNP Saturated Switch Step–Up, External NPN Saturated Switch 1 8 S 170 Ω 7 S Q1 R 1 8 VO U T Q2 Q 4 Q1 R 2 1 70 Ω 7 VO U T Q2 Q 2 R – 0 FOR C O NS TA NT V IN O S CILLA TO R O SC ILL AT O R RS C VI N R SC 6 3 V IN 6 C O M PA RA TO R 5 Semelab plc. 3 C O M PA RA TO R 1.2 5 V R EF ER EN C E RE G UL AT O R 1 .25 V R EF ER EN CE RE G UL ATO R 4 Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. 5 4 Prelim. 2/95 IP35063 IP33063 IP34063 TYPICAL PERFORMANCE CHARACTERISTICS Standby Supply Current vs Supply Voltage 1 00 0 3.2 V CC = 5V 500 C T = 0.001µF Ipk(sense) = VCC ICC SUPPLY CURRENT (mA) OUTPUT SWITCH ON–OFF TIME (µs) Output Switch On–Off Time vs Oscillator Timing Capacitor Pin 5 = Gnd 200 100 t on 50 t off 20 10 5 Ipk(sense) = VCC Pin 2 = Gnd 2.4 1.6 0.8 2 0 1 0.1 0.2 0.5 CT 1 2 5 10 20 50 10 0 0 10 15 20 25 30 40 35 V CC SUPPLY VOLTAGE (V) Emitter–Follower Configuration Output Switch Saturation Voltage vs Emitter Current Common–Emitter Configuration Output Switch Saturation Voltage vs Collector Current 1.2 VCE(sat) SATURATION VOLTAGE (V) 1.6 VCE(sat) SATURATION VOLTAGE (V) 5 OSCILLATOR TIMING CAPACITOR (nF) V CC = 5V Pin 1,7,8 = VCC Pin 3,5 = Gnd 1.5 1.4 1.3 1.2 1.1 1.0 V CC = 5V Pin 7 = VCC Pin 2,3,5 = G nd 1.0 DARLINGTON CONNECTION 0.8 0.6 FORCED β = 20 0.4 0.2 0 0 0.2 0.4 0.6 IE Semelab plc. 0.8 1.0 1.2 1.4 0 0.2 EMITTER CURRENT (A) Telephone (01455) 556565. Telex: 341927. Fax (01455) 552612. 0.4 0.6 IC 0.8 1.0 1.2 1.4 COLLECTOR CURRENT (A) Prelim. 2/95