CYNTEC VPN12AD02-FU, Manual

Page: 1 / 12

Rev. P05 1
VPN12AD02-FU EVB GUIDE
Constant Current for LED Driver Application
ELECTRICAL SPECIFICATION:
Parameters Value Note
Input UVLO Falling 7V
Input UVLO Rising 7.4V
Output OVP / UVP / LED series number 17.6V / 6.8V / 3 ~ 4 LEDs JR25 Jumper short
Output OVP / UVP / LED series number 33.8V / 13V / 5 ~ 8 LEDs JR25 Jumper open
Switching Frequency 350kHz
LED current 1.5A
PROGRAMMING OUTPUT VOLTAGE:
Input UVLO Setting
Input under voltage shutdown levels can both be defined through an external resistor divider.
EN/INUVLO pin voltages are internally compared to their respective thresholds shown as the following
equations. It is recommended that choose R2=10kohm, and R1 can be calculated by following equation.
Input under voltage falling threshold V
EN/INUVLOTH
typical is 1.75V for calculating the VIN UVLO falling.
Input under voltage threshold hysteresis V
EN/INUVLO_HYS
typical is 90mV for calculating the VIN UVLO
rising. Following is some examples for R1, R2 selection.
UVth =
R1
R2
(
+
) V
EN/INUVLOTH
1
.
Table 1: Parameter Value Setting
VIN UVLO Falling 7V
VIN UVLO Rising 7.4V
R1 (
Ω
)
30k
R2 (
Ω
)
10k
Output OVP Setting
The output OVP can be set by the external dividing resistor. VFB typical value is 1.46V. Following are
some output voltage examples.
R22 = R23 x ( -1)
VOUT_OVP
VFB