ncp1392 ON Semiconductor, ncp1392 Datasheet - Page 17

• Manufacturer Part Number: ncp1392
• Description: High-voltage Half-bridge Driver With Inbuilt Oscillator Featuring Brown-out And Autorecovery Enable Input
• Manufacturer: ON Semiconductor

implementation using NCP1392 driver. Voltage across
resistor R1 (R4) increases when converter enters light load
conditions. The enable comparator is triggered when
voltage across R1 is higher than Vref EN + Vf(D1) for
connection from Figure 31 (voltage across R4 is higher than
1.24 V for connection from figure 16). IC then prevents
outputs from pulsing until BO terminal voltage decreases
below 1.92 V.
Figures 31 and 33
IC1
TLV431
R1
R2
C1
R4
R5
V
Q1
CC
shows
Figure 33. Skip Mode Feature Implementation (Better Accuracy)
R6
R3
Voltage
Feedback
skip
mode
C
R
SS
fstart
V
bulk
R
R
feature
upper
lower
http://onsemi.com
R
t
BO
Rt
17
I
hyste
overvoltage protection. When bulk voltage is too high, the
enable input is triggered via BO divider.
The High−Voltage Driver
high−voltage section. The device incorporates an upper
UVLO circuitry that makes sure enough V
the upper side MOSFET. The V
is provided by C
bootstrap diode.
Note that enable comparator serves also as an automatic
Figure 34 shows the internal architecture of the
SW
+
−
+
−
V
V
refEN
refBO
boot
+
−
−
+
GND
High Level for 50 ms after V
NCP1392
capacitor that is refilled by external
0.5ms
Filter
Filter
20ms
CC
for floating driver section
CC
ON
To PFC Delay
gs
to AND gates
to AND gates
is available for