THV3058 Datasheet, PDF (15/21 Pages) THine Electronics, Inc. – 3CH (Buck/Boost) 2CH CP 1CH HVLDO Controller

THV3058_Rev.1.00_E
● Over Current Protection(OCP)
CH-1, CH-2 and CH-3 have built-in over current protection circuit. Over current detection circuit monitors the load cur-
rent. When load current exceeds a predetermined current, the external MOS transistor is turned off and the device stops
switching operation for 128usec(See Figure 7, 8, 9). The maximam current are given by the following formulas.
I _max1
=
Vin _×
Vo1
Vcs1
Rcs1
=
Vin _×
Vo1
0.1
Rcs1
[A]
I _max2
=
Vcs2
Rcs2
=
0.1
Rcs2
[A]
I _max3
=
Vcs3
Rcs3
=
0.175
Rcs3
[A]
If the over current is detected continuously, the switching pulse is generated at 128usec interval and that causes output
voltage drop. When the output voltage drops below the predetermined voltage for more than 12.2msec, SCP stops switch-
ing operation and the device goes into latch state.
Vin
PWM COMP
+
-
Vcs1=0.1V
VO1
OUT1
CS1
Output
current
Io1
PGND
Rcs1
Detection
current
Figure.7 CH-1 Over Current Detection Circuit
VREG5
PWM COMP
+
-
Vcs3=0.10V
Vin
BST2
OUT_H2
LL2
OUT_L2
CS2
PGND
Rcs2
VO2
Detection
current
Output
current
Io2
Figure.8 CH-2 Over Current Detection Circuit
VREG5
Vin
PWM COMP
+
-
Vcs3=0.175V
BST3
OUT3
LL3
CS3
PGND Rcs3
VO3=3.3V
Detection
current
Output
current
Io3
Figure.9 CH-3 Over Current Detection Circuit
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15/21
THine Electronics, Inc.