Led7707 Demonstration Board - STMicroelectronics LED7707 Application Note

AN2810
2

LED7707 demonstration board

The LED7707 demonstration board has been designed to manage six strings of 8 to 10
white LEDs each.
Table 1 summarizes the board features and
board schematic. The input voltage range is limited to 32 V because of the 35 V rated input
capacitor. An extended operating input voltage range (up to 36 V) can be achieved by using
a 50 V-rated MLCC.
Table 1.
Minimum input voltage
Maximum input voltage
Output OVP threshold
Internal MOSFET OCP
Boost section switching frequency
Minimum dimming on-time
Output current (each row)
Output current accuracy
Figure 2.
LED7707 performance summary
Parameter
Output voltage
Efficiency
LED7707 demonstration board schematic
Doc ID 14893 Rev 1
LED7707 demonstration board
Figure 2 shows the LED7707 demonstration
Conditions
R =510 kΩ, R2=16 kΩ
1
R =360 kΩ
7
FSW pin to AVCC
FSW pin to R =330 kΩ
5
400 Hz<F <20 kHz
DIM
R =24 kΩ
6
V =12V , V =34 V,
IN BOOST
F =660 kHz
SW
Value
6 V
32 V
V <V <36 V
IN BOOST
38 V
3.3 A
660 kHz
825 kHz
10 µs
75 mA
±2%
91%
5/17