 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
MC34065 Datasheet(PDF) 4 Page - ON Semiconductor |
|
||||||||||||||||||||||||||||||
MC34065 Datasheet(HTML) 4 Page - ON Semiconductor |
|
|
4 / 15 page 
MC34065 MC33065 4 MOTOROLA ANALOG IC DEVICE DATA PIN FUNCTION DESCRIPTION Pin Function Description 1 Sync Input A narrow rectangular waveform applied to this input will synchronize the oscillator. A dc voltage within the range of 2.4 V to 5.5 V will inhibit the oscillator. 2 CT Timing capacitor CT connects from this pin to ground setting the free–running oscillator frequency range. 3 RT Resistor RT connects from this pin to ground precisely setting the charge current for CT. RT must be between 4.0 k and 16 k. 4 Voltage Feedback 1 This pin is the inverting input of Error Amplifier 1. It is normally connected to the switching power supply output through a resistor divider. 5 Compensation 1 This pin is the output of Error Amplifier 1 and is made available for loop compensation. 6 Current Sense 1 A voltage proportional to the inductor current is connected to this input. PWM 1 uses this information to terminate conduction of output switch Q1. 7 Drive Output 1 This pin directly drives the gate of a power MOSFET Q1. Peak currents up to 1.0 A are sourced and sunk by this pin. 8 Gnd This pin is the control circuitry ground return and is connected back to the source ground. 9 Drive Gnd This pin is a separate power ground return that is connected back to the power source. It is used to reduce the effects of switching transient noise on the control circuitry. 10 Drive Output 2 This pin directly drives the gate of a power MOSFET Q2. Peak currents up to 1.0 A are sourced and sunk by this pin. 11 Current Sense 2 A voltage proportional to inductor current is connected to this input. PWM 2 uses this information to terminate conduction of output switch Q2. 12 Compensation 2 This pin is the output of Error Amplifier 2 and is made available for loop compensation. 13 Voltage Feedback 2 This pin is the inverting input of Error Amplifier 2. It is normally connected to the switching power supply output through a resistor divider. 14 Drive Output 2 Enable A logic low at this input disables Drive Output 2. 15 Vref This is the 5.0 V reference output. It can provide bias for any additional system circuitry. 16 VCC This pin is the positive supply of the control IC. The minimum operating voltage range after startup is 11 V to 15.5 V. Figure 1. Timing Resistor versus Oscillator Frequency Figure 2. Maximum Output Duty Cycle versus Oscillator Frequency 4.0 6.0 8.0 10 14 16 fosc, OSCILLATOR FREQUENCY (Hz) 12 3.3 nF 500 pF 220 pF 330 pF 5.0 nF 1.0 nF 10 k 30 k 50 k 300 k 500 k 100 k 1.0 M 100 pF fosc, OSCILLATOR FREQUENCY (Hz) 38 40 42 44 48 50 46 Output 2 Output 1 10 k 30 k 50 k 300 k 500 k 100 k 1.0 M VCC =15 V RT = 4.0 k to 16 k CL =15 pF TA = 25° CT = 10 nF VCC =15V TA =25°C 2.2 nF |
English ▼
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
