Details

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BUY UC3842A https://www.utsource.net/itm/p/9836161.html

Parameter	Symbol	Conditions	Min	Typ	Max	Unit
Supply Voltage	Vcc	Operating	10	16.5	30	V
Start-Up Current	ISTART			2.5		mA
Operating Current	IOP			15		mA
Quiescent Current	IQ	No load		8		mA
Error Amplifier Gain	AEA		40		120	dB
Frequency Compensation
Slope						V/μs
Output Drive Capability	IDRV		100		400	mA
Maximum Duty Cycle	DMAX			97		%
Minimum ON-Time	TONMIN		500			ns
Minimum OFF-Time	TOFFMIN		800			ns
Oscillator Frequency Range	FOSC	RT = 1 kΩ, CT = 1 nF	1	500	1000	kHz
Thermal Shutdown	TSD		160			°C
Hysteresis	THYS		10			°C

Instructions for UC3842A:

1. Power Supply Connection:

   • Connect the supply voltage (Vcc) within the operating range of 10V to 30V.

2. Start-Up and Operating Current:

   • Ensure that the start-up current does not exceed 2.5mA and the operating current remains around 15mA.

3. Error Amplifier:

   • The error amplifier has a gain between 40dB and 120dB. Use external frequency compensation components as necessary.

4. Output Drive:

   • The output can drive up to 400mA peak current. Ensure the load is within this limit.

5. Duty Cycle and Timing:

   • Set the maximum duty cycle to no more than 97%. The minimum on-time is 500ns and the minimum off-time is 800ns.

6. Oscillator Configuration:

   • Configure the oscillator frequency using external resistors (RT) and capacitors (CT). For example, with RT = 1kΩ and CT = 1nF, the frequency range is from 1kHz to 1000kHz.

7. Thermal Protection:

   • The device includes thermal shutdown protection which activates at approximately 160°C with a hysteresis of about 10°C.

8. Application Considerations:

   • Carefully design the power supply and heat dissipation to avoid exceeding the thermal shutdown threshold.
   • Ensure all external components are rated for the intended application conditions.

These parameters and instructions should be used as guidelines for designing circuits with the UC3842A. Always refer to the manufacturer's datasheet for detailed specifications and recommendations.

(For reference only)