Details

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BUY VIPER20B https://www.utsource.net/itm/p/1838341.html
SMPS PRIMARY I.C.

Parameter	Description	Value	Unit
VCC	Supply Voltage	14.5 to 70	V
IOUT	Output Current (Peak)	1.2	A
fSW	Switching Frequency	65 to 132	kHz
VFB	Feedback Voltage	2.5	V
ISTART	Start Current	35	μA
IHOLD	Hold Current	8	μA
RTH	Thermal Resistance (Junction to Ambient)	65	°C/W
TJ	Junction Temperature Range	-40 to 150	°C
PDISS	Power Dissipation (Max)	1.5	W
VUVLO	Under-Voltage Lockout Threshold	11.5	V
tDELAY	Delay Time	10	μs
VDRIVE	Gate Drive Voltage	12 to 18	V

Instructions for Using VIPER20B

1. Supply Voltage (V_CC):

   • Ensure the supply voltage is within the range of 14.5V to 70V. Operating outside this range can damage the device.

2. Output Current (I_OUT):

   • The peak output current should not exceed 1.2A to avoid overheating and potential failure.

3. Switching Frequency (f_SW):

   • The switching frequency is typically between 65kHz and 132kHz. Adjust the external components to set the desired frequency.

4. Feedback Voltage (V_FB):

   • Set the feedback voltage to 2.5V for optimal regulation. Use a voltage divider network to achieve this value.

5. Start and Hold Current (I_START, I_HOLD):

   • The start current is 35μA, and the hold current is 8μA. Ensure the power supply can provide these currents to initiate and maintain operation.

6. Thermal Management:

   • The thermal resistance (R_TH) is 65°C/W. Use appropriate heat sinks or cooling methods to keep the junction temperature within the -40°C to 150°C range.

7. Power Dissipation (P_DISS):

   • The maximum power dissipation is 1.5W. Ensure the device is not subjected to excessive power dissipation to prevent overheating.

8. Under-Voltage Lockout (V_UVLO):

   • The device will shut down if the supply voltage drops below 11.5V to protect against low-voltage conditions.

9. Delay Time (t_DELAY):

   • There is a 10μs delay time before the device starts operating after power is applied. This delay helps in stabilizing the circuit.

10. Gate Drive Voltage (V_DRIVE):

    • The gate drive voltage should be between 12V and 18V to ensure proper switching of the internal MOSFET.

By following these parameters and instructions, you can effectively use the VIPER20B in your power supply design.

(For reference only)