Details

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BUY UC2844B https://www.utsource.net/itm/p/12597604.html

Parameter	Symbol	Min	Typical	Max	Unit	Notes
Supply Voltage	Vcc	13	-	40	V
Start-Up Current	ISTR	-	1.0	-	mA
Operating Current	Icc	-	3.5	-	mA
Under-Voltage Lockout	UVLO	9.5	-	11	V
Frequency Set	RT	-	2.7	-	k惟	For 100 kHz operation
Frequency Set	CT	-	1.0	-	nF	For 100 kHz operation
Oscillator Frequency	fosc	-	100	-	kHz
Dead Time	Td	0.5	-	1.5	渭s
Maximum Duty Cycle	Dmax	-	50	-	%
Error Amplifier Gain	Aea	-	25	-	V/渭A
Error Amplifier Input Bias Current	Iea	-	0.1	-	渭A
Soft-Start Capacitance	CSS	-	0.1	-	渭F
Soft-Start Time	Tss	-	1.6	-	ms	With 0.1 渭F capacitor
Output High Voltage	VOH	11	-	13	V
Output Low Voltage	VOL	-	0.5	1.5	V
Output Sink Current	ISNK	-	200	-	mA
Output Source Current	ISRC	-	100	-	mA
Thermal Shutdown	TSD	-	160	-	掳C
Storage Temperature	Tstg	-40	-	125	掳C

Instructions for Using UC2844B:

1. Supply Voltage (Vcc):

   • Ensure the supply voltage is within the range of 13V to 40V.
   • Use a bypass capacitor (typically 0.1 渭F) from Vcc to ground to filter out noise.

2. Under-Voltage Lockout (UVLO):

   • The IC will not operate if the Vcc falls below 9.5V.
   • It will restart once Vcc rises above 11V.

3. Frequency Set (RT and CT):

   • Set the oscillator frequency using external resistors (RT) and capacitors (CT).
   • For 100 kHz operation, use RT = 2.7 k惟 and CT = 1.0 nF.

4. Dead Time (Td):

   • The dead time is the period during which both output transistors are off to prevent shoot-through.
   • It typically ranges from 0.5 渭s to 1.5 渭s.

5. Maximum Duty Cycle (Dmax):

   • The maximum duty cycle is limited to 50% to ensure proper operation and prevent overloading.

6. Error Amplifier:

   • The error amplifier compares the feedback voltage with a reference voltage.
   • Use a compensation network to stabilize the loop.

7. Soft-Start (CSS):

   • Connect a capacitor (CSS) to the soft-start pin to control the startup time.
   • A typical value is 0.1 渭F, which results in a soft-start time of approximately 1.6 ms.

8. Output Stage:

   • The output stage can source up to 100 mA and sink up to 200 mA.
   • Ensure the load is within these limits to avoid damage.

9. Thermal Shutdown (TSD):

   • The IC will shut down if the temperature exceeds 160掳C to protect against overheating.
   • Ensure proper heat dissipation and cooling.

10. Storage Temperature (Tstg):

    • Store the IC in an environment where the temperature ranges from -40掳C to 125掳C.

By following these parameters and instructions, you can effectively design and implement circuits using the UC2844B.

(For reference only)