STMicroelectronics HVLED805 Evaluation Board EVALHVLED805 EVALHVLED805 데이터 시트
제품 코드
EVALHVLED805
Application information
HVLED805
24/29
Doc ID 18077 Rev 1
before the V
CC
capacitor is charged again and the device restarted. Ultimately, this will
result in a low-frequency intermittent operation (Hiccup-mode operation), with very low
stress on the power circuit. This special condition is illustrated in the timing diagram of
stress on the power circuit. This special condition is illustrated in the timing diagram of
.
5.10 Layout
recommendations
A proper printed circuit board layout is essential for correct operation of any switch-mode
converter and this is true for the HVLED805 as well. Careful component placing, correct
traces routing, appropriate traces widths and compliance with isolation distances are the
major issues. In particular:
converter and this is true for the HVLED805 as well. Careful component placing, correct
traces routing, appropriate traces widths and compliance with isolation distances are the
major issues. In particular:
●
The compensation network should be connected as close as possible to the COMP
pin, maintaining the trace for the GND as short as possible
pin, maintaining the trace for the GND as short as possible
●
Signal ground should be routed separately from power ground, as well from the sense
resistor trace.
resistor trace.
Figure 19.
Hiccup-mode OCP: timing diagram
V
DS
Vcc
ON
Vcc
OFF
Vcc
rest
Secondary diode is shorted here
t
t
t
V
SOURCE
1 V
Two switching cycles
V
CC
Vcs
dis