NCP1392B_09 ONSEMI [ON Semiconductor], NCP1392B_09 Datasheet - Page 18

• Manufacturer Part Number: NCP1392B_09
• Description: High-Voltage Half-Bridge Driver with Inbuiltc Oscillator
• Manufacturer: ONSEMI [ON Semiconductor]

application by adding two bipolar transistors (Figure 14).
Transistor Q2 pullup BO input when dimming signal is high.
The dimming feature can be easily aid to the ballast
Q2
Figure 38. Skip Mode with Transistor Feature Implementation (Temperature Dependent, Cost Effective)
R1
R2
R1
C1
Soft−Start After Skip (If Needed)
D1
R2
Figure 37. Skip Mode Feature Implementation (Temperature Dependent, Cost Effective)
V
Q1
CC
R4
R6
R3
D1
R5
Voltage
Feedback
Voltage
Feedback
C
R
SS
fstart
V
bulk
R
R
C
upper
lower
R
SS
fstart
R
t
V
bulk
BO
Rt
R
R
http://onsemi.com
upper
lower
R
t
I
hyste
BO
Rt
SW
18
I
hyste
In the same time the Q1 discharges soft start capacitor via
diode D1. Ballast application is enabled (including
soft−start phase) when dimming signal becomes low again.
SW
+
−
+
−
V
V
refEN
refBO
High Level for BOdisch time after V
+
−
−
+
GND
+
− −
+
−
V
V
refEN
refBO
NCP1392
High Level for BOdisch time after V
+
−
−
+
GND
Filter
20ms
NCP1392
0.5ms
Filter
0.5ms
Filter
Filter
20ms
To PFC Delay
CC
to AND gates
to AND gates
ON
To PFC Delay
CC
to AND gates
to AND gates
ON