KA7500 Description The KA7500 incorporate on a single monolithic chip all the functions required in the construction of a pulse-width-modulation control circuit. Designed primarily for power supply control ,these devices offer the systems engineer the flexibility to tailor the power supply control circuitry to hos application. The K A7500 contains an error amplifier , anon-chip adjustable oscillator ,a dead- time control comparator ,pulse-steering control flip-flop ,a 5-volt, 1% precision regulator , and output-control circuits. The error amplifier exhibits a common-mode voltage range from -0.3 volts to Vcc -2 volts .The dead time control comparator has a fixed offset that provides approximately 5% deed time when externally altered. The on-chip oscillator may be bypassed by terminating RT (pin 6 ) to the reference output and providing a sawtooth input to Ct (pin 5) ,or it may be used to drive the common circuits in synchronous multiple-rail power supplies . The uncommitted output transistors provide either common circuits in synchronous Power supplier.The uncommitted output transistors provide either common-emitter or emitter-follower output capability .Each device provides for push-pull or single-ended output operation, which may be selected throug h the outpu t - control function . Th e architecture of these devices prohibits the possibility of either output being pulsed twice during push-pull operation. Features • Complete PWM Power Control Circuitry Uncommitted Outputs for 200 mA sink or Source Current Output control Selects Singel-Ended or Push-Pull operation • Internal Circuitry Prohibits Double Pulse at Either output • Variable Dead-Time Provides Control over Total Range Internal Regulator Provides a Stable 5-V Reference supply ,1% Circuit Architecture Allows Easy Synchronization DIP - 16 Block Digram Package BEIJING ESTEK ELECTRONICS CO.,LTD 1 KA7500 Absolute Maximum Ratings Over Operating Free-air Temerature Range (Unless Otherwise Noted) Rating Supply voltage ,Vcc Amplifier input voltage Collector output voltage Collector output current Operating free-air temperature range Storage temperature range Lead temperature 1,6 mm from case for 10 seconds Value 41 Vcc+0.3 41 250 0 to 70 -65 to 150 260 Unit V mA °C Recommended Operating Conditions Parameter Value MIN 7 -0.3 Supply voltage ,Vcc Amplifier input voltage ,Vi Collector output voltage ,Vo Collector output current (each transistor) Current into feedback terminal Timing capacitor ,CT Timing resistor ,RT Oscillator frequency Operating free-air temperature ,TA Unit MAX 40 Vcc-2 40 200 0.3 10 500 200 70 0.0047 1.8 1 0 V mA µF kΩ kHz °C Electrical Characteristics Over Operating Free-air Temerature Range,Vcc=15V,f=10kHz Noted) (Unless Otherwise Reference Section Parameter Output voltage(Vref) Line regulation Load regulation Short-circuit output current*** Test conditions Io=1mA Io=1mA,TA=25°C**** Vcc=7V to 40V Io=1Ma to 10mA Vref=0 MIN 4.9 4.95 10 Value TYP** 5 5 2 1 35 Unit MAX 5.1 5.05 25 15 50 V mV mA BEIJING ESTEK ELECTRONICS CO.,LTD 2 KA7500 Oscillator section (See Figure 1) Parameter Test conditions* Frequency Frequency Frequency change with temperature ***** Value TYP** 10 - MIN 9.2 9.0 CT=0.01µF,RT=12KΩ,TA=25°C CT=0.01µF,RT=12KΩ CT=0.01µF,RT=12KΩ ΔTA=MIN TO MAX Unit MAX 10.8 12 2 kHz Amplifier section (See Figure 2) Parameter Test conditions Value TYP* 2 25 0.2 MIN Input offset voltage Input offset current Input blas current Common-mode input voltage range Open-loop voltage amplification Unity-gain bandwidth Vo(pin 3)=2.5V Vo(pin 3)=2.5V Vo(pin 3)=2.5V Vcc=7V to 40V ΔVo=3V,RL=2KΩ, -0.3 to Vcc-2 70 Unit MAX 10 250 1 95 650 mV nA µA V dB kHz Output Section Parameter Test conditions MIN Collector off-state current Emitter off-state current Collector-emitter saturation voltage Output control input current Common-emitter Emitter-follower VCE=40V,Ccc=40V Vcc=Vc=40V,VE=0 VE=0,Ic=200mA VC=15V,IE=-200mA VI=Vref Value TYP** 2 1.1 1.5 Unit MAX 100 -100 1.3 2.5 3.5 µA V mA Dead -Time Control - Section(See Figure 1) Parameter Test conditions MIN Input bias current (pin 4) Maximum duty cycle, each output Input threshold voltage (pin 4) P VI=0 to 5.25V VI(pin 4)=0,O.C.=Vref Zero duty cycle Maximum duty cycle Value TYP** -2 Unit MAX -10 3 3.3 Value TYP** 4 0.7 MAX 4.5 45 µA % V 0 M Comparator Section(See Figure 1) Parameter Test conditions MIN Input threshold voltage(pin 3) Input sink current (pin 3) Zero duty cycle V(pin 3)=0.7V 0.3 Unit V mA BEIJING ESTEK ELECTRONICS CO.,LTD 3 KA7500 Total Device Parameter Test conditions MIN Standby supply current Pin 6 at Vref Switching Characteristics, T Parameter Vcc=15V Unit MAX 10 mA 25 o C Test conditions MIN Output voltage rise time Output voltage fall time Output voltage rise time Output voltage fall time Value TYP** 6 Common-emitter configuration, See figure 3 Emitter-follower configuration. See Figure 4 Value TYP** 100 25 100 25 Unit MAX 200 100 200 100 ns *For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions. **All typical values except for parameter changes with temperature are at TA=25°C ***Duration of the short-circuit should not exceed one second ****This is guaranteed where the marking code on the package surface is “A” *****Temperature coefficient of timing capacitor and timing resistor not taken into account. Parameter Measurement Information BEIJING ESTEK ELECTRONICS CO.,LTD 4 KA7500 Figure 1. Operational test circuit and waveforms Figure 2.Amplifier characteristics BEIJING ESTEK ELECTRONICS CO.,LTD 5 KA7500 Figure 3. Common - emitter configuration Figure 4. Emitter - follower configuration Ordering Information O RDERI NG NUM BER R KA7500 Address : P ACK AGE DIP-16 M AR K ING KA7500 6A06--6A07 Rm 6A07,Changyin Office Building ,No.88,Yong Ding Road,Hai Dian District ,Beijing Postalcode:100039 Tel: 86-010-58895780 / 81 / 82 / 83 / 84 Fax : 010-58895793 Http://www.estek.com.cn Email:[email protected] REV No:01-060816 BEIJING ESTEK ELECTRONICS CO.,LTD 6