1A STEP-DOWN/STEP-UP/INVERTING DC-DC CONVERTER General Description. Features. Applications

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1 General Description The is a monolithic switching regulator control circuit which contains the primary functions required for DC-DC converters. This device consists of internal temperature compensated reference, voltage comparator, controlled duty cycle oscillator with active current limit circuit, driver and high current output switch. The is specifically designed as a general DC-DC converter to be used in Step-Down, Step-Up and Voltage-Inverting applications with a minimum number of external components. The is available in 2 packages: SOIC-8 and DIP-8. Features Operation from 3.0V to 36V Input Low Standby Current Current Limiting Output Switch Current toa Output Voltage Adjustable Operation Frequency up to 80kHz ( =00pF) Precision 2% Reference Applications Battery Chargers ADSL Modems Hubs Negative Voltage Power Supplies SOIC-8 DIP-8 Figure. Package Types of

2 Pin Configuration M Package (SOIC-8) P Package (DIP-8) Switch Collector Switch Emitter Timing Capacitor GND Driver Collector I PK Sense Comparator Inverting Input Switch Collector Switch Emitter Timing Capacitor GND Driver Collector I PK Sense Comparator Inverting Input Figure 2. Pin Configuration of (Top View) Functional Block Diagram Driver Collector 8 B A S Q Switch Collector R I PK Sense 7 Ipk I PK 2 Switch Emitter OSC 6 3 Timing Capacitor -.25V Reference Regulator Comparator Inverting Input 5 4 GND Figure 3. Functional Block Diagram of 2

3 Pin Description Pin Number Pin Name Function Switch Collector Internal switch transistor collector 2 Switch Emitter Internal switch transistor emitter 3 Timing Capacitor Timing Capacitor to control the switching frequency 4 GND Ground pin for all internal circuits 5 Comparator Inverting Input Inverting input pin for internal comparator 6 Voltage supply 7 I PK Sense Peak Current Sense Input by monitoring the voltage drop across an external current sense resistor to limit the peak current through the switch 8 Driver Collector Voltage driver collector Ordering Information - Circuit Type Package M: SOIC-8 P: DIP-8 G: Green TR: Tape and Reel Blank: Tube Package Temperature Range Part Number Marking ID Packing Type M-G 34063DM-G Tube SOIC-8-40 to 85 o C MTR-G 34063DM-G Tape & Reel DIP-8-40 to 85 o C P-G P-G Tube BCD Semiconductor's Pb-free products, as designated with "G" suffix in the part number, are RoHS compliant and green. 3

4 Absolute Maximum Ratings (Note ) Parameter Symbol Value Unit Power Supply Voltage 40 V Comparator Input Voltage Range V IR -0.3 to 40 V Switch Collector Voltage V C (switch) 40 V Switch Emitter Voltage (V PIN =40V) V E (switch) 40 V Switch Collector to Emitter Voltage V CE (switch) 40 V Driver Collector Voltage V C (driver) 40 V Driver Collector Current (Note 2) I C (driver) 00 ma Switch Current I SW A Power Dissipation (T A =25 o C) DIP-8 P D.25 W SOIC mw Thermal Resistance DIP-8 θ JA 00 SOIC-8 60 o C/W Operating Junction Temperature T J 50 o C Lead Temperature (Soldering, 0s) T LEAD 260 o C Storage Temperature Range T STG -65 to 50 o C ESD (Human body model) 2000 V Note : Stresses greater than those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "Recommended Operating Conditions" is not implied. Exposure to "Absolute Maximum Ratings" for extended periods may affect device reliability. Note 2: Maximum package power dissipation limits must be observed. Recommended Operating Conditions Parameter Symbol Min Max Unit Supply Voltage 3 36 V Ambient Temperature T A o C 4

5 Electrical Characteristics ( =5.0V, T A =-40 to 85 o C, unless otherwise specified.) Parameter Symbol Conditions Min Typ Max Unit OSCILLATOR V Frequency f PIN5 =0V, =.0nF KHz OSC T A =25 o C =330pF KHz Charge Current I CHG VCC =5.0V to 36 V, T A =25 o C µa Discharge Current I DISCHG VCC =5.0V to 36V, T A =25 o C µa Discharge to Charge Current Ratio I DISCHG /I CHG Pin 7 to, T A =25 o C Current Limit Sense Voltage V IPK (sense) I CHG =I DISCHG, T A =25 o C mv OUTPUT SWITCH (Note 3) Saturation Voltage, Dalington Connection Saturation Voltage (Note 4) V CE (sat) V CE (sat) I SW =A, Pins, 8 connected, Common Emitter I SW =A, R PIN8 =82 Ω to, Forced β=20, Common Emitter DC Current Gain h FE ISW =A, V CE =5.0V, T A =25 o C V 0.45 V Collector Off-State Current I C (off) V CE =36V µa COMPARATOR Threshold Voltage V TH T A =25 o C V T A =-40 to 85 o C Threshold Voltage Line Regulation R EGLINE =3.0V to 36V.4 5 mv Input Bias Current I IB V IN =0V na TOTAL DEVICE Supply Current I CC =5.0V to 36V, =.0 nf, V PIN7 =, V PIN5 > V TH, 4 ma V PIN2 =GND, other pins open Note 3: Low duty cycle pulse technique are used during test to maintain junction temperature as close to ambient temperature as possible. Note 4: If the output switch is driven into hard saturation (non-darlington configuration) at low switch currents ( 300mA) and high driver currents ( 30mA), it may take up to 2.0µs for it to come out of saturation. This condition will shorten the off time at frequencies 30KHz, and is magnified at high temperatures. This condition does not occur with a Darlington configuration, since the output switch cannot saturate. If a non-darlington configuration is used, the following output drive condition is recommended: 5

6 Electrical Characteristics (Continued) I C output Forced β of output switch: 0 I C driver - 7.0mA* * The 00Ω resistor in the emitter of the driver device requires about 7.0 ma before the output switch conducts. Typical Performance Characteristics ( =5.0V, T A =25 o C, unless otherwise specified.) Ton-off Output Switch On-Off Time (µs) =5.0V V PIN7 = V PIN5 =GND T A =25 O C t on t off Vosc Oscillator Voltage (V) 200mV/DIV =5.0V V PIN7 = V PIN2 =GND Pin,5,8=open =.0nF T A =25 o C Oscillator Timing Capacitor (nf) Time 20µs/DIV Figure 4. Output Switch On-Off Time vs. Oscillator Timing Capacitor Figure 5. Timing Capacitor Waveform 3.5 =5.0V Oscillator Frequency (khz) 00 0 V PIN7 = V PIN5 =GND T A =25 O C I CC Supply Current (ma) =.0nF V PIN7 = V PIN2 =GND Timing Capacitor (nf) Supply Voltage (V) Figure 6. Oscillator Frequency vs.timing Capacitor Figure 7. Standby Supply Current vs. Supply Voltage 6

7 Typical Performance Characteristics (Continued) ( =5.0V, T A =25 o C, unless otherwise specified.) Saturation Voltage (V) Emitter Current (A) =5.0V V PIN,7,8 = V PIN3,5 =GND T A =25 O C Saturation Voltage (V) Darlington Connection Forced β=20 =5.0V V PIN7 = V PIN2,3,5 =GND T A =25 O C Collector Current (A) Figure 8. Emitter Follower Configuration Output Saturation Voltage vs. Emitter Current Figure 9. Common Emitter Configuration Output Switch Saturation Voltage vs. Collector Current Current Limit Sense Voltage (mv) Feedback Voltage (V) Temperature ( O C) Temperature ( O C) Figure 0. Current Limit Sense Voltage vs. Temperature Figure. Feedback Voltage vs. Temperature 7

8 Typical Performance Characteristics (Continued) ( =5.0V, T A =25 o C, unless otherwise specified.) Operation Frequency (khz) =5.0V =330pF Saturation Voltage (V).2.0 I SW =.0A =5.0V PIN PIN8 Connected Temperature ( O C) Temperature ( o C) Figure 2. Operation Frequency vs. Temperature Figure 3. Saturation Voltage vs. Temperature 8

9 Typical Applications L 220µH R B A S R Q 7 2 Rsc 0.4 IpkI PK OSC D N589 V IN 2V 6 3 C 00µF -.25V Reference Regulator 470pF 5 4 U L2.0µH V OUT V OUT R2 2.2k R 47k 28V/75mA C2 330 µf Optional Filter C3 00 µf Figure 4. Step-Up Converter (Note 5) Note 5: This is a typical step-up converter configuration. In the steady state, if the resistor divider voltage at pin 5 is greater than the voltage in the non-inverting input, which is.25v determined by the internal reference, the output of the comparator will go low. At the next swithching period, the output switch will not conduct and the output voltage will eventually drop below its nominal voltage until the divider voltage at pin 5 is lower than.25v. Then the output of the comparator will go high, the output switch will be allowed to conduct. Since V PIN5 =V OUT * R2/(RR2)=.25(V), the output voltage can be decided by V OUT =.25 * (RR2)/R2 (V). 9

10 Typical Applications (Continued) 8 B A S R Q 7 2 V IN 25V Rsc Ipk I PK OSC 3 D N589 L 220 µh C 00µF -.25V Reference Regulator CT 470 pf 5 4 U L2.0 µh V OUT V OUT R2.2k R 3.6k 5V/500mA C2 470 µf Optional Filter C3 00 µf Figure 5. Step-Down converter (Note 6) Note 6: This is a typical step-down converter configuration. The working process in the steady state is similar to step-up converter, V PIN5 =V OUT *R2/(RR2)=.25 (V), the output voltage can be decided by V OUT =.25* (RR2)/R2 (V). 0

11 Typical Applications (Continued) 8 B A S R Q 7 2 Rsc 0.24 Ipk I PK OSC L 88 µη V IN 4.5-6V 6 3 C 00 µf -.25V Reference Regulator 470pF D N U L2.0 µh V OUT V OUT R2 8.2k R 953-2V/00mA C2 000 µf Optional Filter C3 00 µf Figure 6. Voltage Inverting Converter (Note 7) Note 7: This is a typical inverting converter configuration. The working process in the steady state is similar to step-up converter, the difference in this situation is that the voltage at the non-inverting pin of the comparator is equal to.25vv OUT, then V PIN5 =V OUT *R2/(RR2)=.25VV OUT, so the output voltage can be decided by V OUT =-.25*(RR2)/R (V).

12 Mechanical Dimensions SOIC-8 Unit: mm(inch) (0.85) 5.00(0.20).350(0.053).750(0.069) 0.320(0.03) 8.000(0.039) 7.270(0.050) TYP 0.00(0.004) 0.300(0.02) R0.50(0.006) 0.675(0.027) 0.725(0.029) D 0 8 D 20: (0.228) 6.200(0.244) 0.800(0.03) 0.200(0.008) 3.800(0.50) 4.000(0.57) 0.330(0.03) 0.50(0.020) 0.90(0.007) 0.250(0.00) 0.900(0.035) (0.07) 0.800(0.03) R0.50(0.006) Note: Eject hole, oriented hole and mold mark is optional. 2

13 Mechanical Dimensions (Continued) DIP-8 Unit: mm(inch) 0.700(0.028) 6.524(0.060) TYP (0.300)TYP (0.46) 4.30(0.70) (0.26) 3.600(0.42) (0.8) 3.600(0.42) 0.50(0.020)MIN 0.254(0.00)TYP 0.360(0.04) 0.560(0.022) 0.30(0.005)MIN 2.540(0.00) TYP 8.200(0.323) 9.400(0.370) 0.204(0.008) 0.360(0.04) R0.750(0.030) 6.200(0.244) 6.600(0.260) Φ3.000(0.8) Depth 0.00(0.004) 0.200(0.008) 9.000(0.354) 9.400(0.370) Note: Eject hole, oriented hole and mold mark is optional. 3

14 BCD Semiconductor Manufacturing Limited IMPORTANT NOTICE BCD Semiconductor Manufacturing Limited reserves the right to make changes without further notice to any products or specifications herein. BCD Semiconductor Manufacturing Limited does not assume any responsibility for use of any its products for any particular purpose, nor does BCD Semiconductor Manufacturing Limited assume any liability arising out of the application or use of any its products or circuits. BCD Semiconductor Manufacturing Limited does not convey any license under its patent rights or other rights nor the rights of others. MAIN SITE BCD - Headquarters Semiconductor Manufacturing Limited - Wafer BCD FabSemiconductor Manufacturing Limited BCD - Wafer Semiconductor Fab Manufacturing Limited Shanghai - IC Design SIM-BCD Group Semiconductor Manufacturing Co., Ltd. No. Shanghai 600, Zi SIM-BCD Xing Road, Semiconductor Shanghai ZiZhu Manufacturing Science-based Limited Industrial Park, 20024, China 800 Yi Advanced Shan Road, Analog Shanghai Circuits , (Shanghai) China Corporation Tel: 800, , Yi Shan Road, Shanghai Fax: , China Tel: F, Zone B, 900, 49, Yi Fax: Shan Road, Shanghai , China Tel: , Fax: Tel: , Fax: REGIONAL SALES OFFICE REGIONAL Shenzhen OfficeSALES OFFICE Shenzhen Shanghai SIM-BCD Office Semiconductor Manufacturing Co., Ltd., Shenzhen Office Shanghai Unit A Room SIM-BCD 203, Skyworth Semiconductor Bldg., Gaoxin Manufacturing Ave..S., Nanshan Co., Ltd. District, Shenzhen Shenzhen, Office Advanced China Analog Circuits (Shanghai) Corporation Shenzhen Office Taiwan Office BCD Taiwan Semiconductor Office (Taiwan) Company Limited 4F, 298-, BCD Rui Semiconductor Guang Road, (Taiwan) Nei-Hu District, Company Taipei, Limited Taiwan 4F, 298-, Rui Guang Road, Nei-Hu District, Taipei, USA Office USA BCD Office Semiconductor Corp. BCD Semiconductor Huntwood Ave. Corporation Hayward, CA 94544, Huntwood USA Ave. Hayward, Room Tel: E, 5F, Noble 795 Center, No.006, 3rd Fuzhong Road, Futian District, Shenzhen 58026, China Tel: Taiwan 2808 CA Tel : 94544, U.S.A Tel: Fax: Fax: Fax: Tel: Fax: Tel Fax: : Fax: