Datasheet

MAX17113
Low-Cost, Multiple-Output
Power Supply for LCD TVs
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High-Voltage Switch Control
The MAX17113’s high-voltage switch control block
(Figure 5) consists of two high-voltage p-channel
MOSFETs: Q1, between SRC and GON and Q2, between
GON and DRN. The switch control block is enabled when
V
DLP
exceeds V
REF
. Q1 and Q2 are controlled by CTL
and MODE. There are two different modes of operation
(see the
Typical Operating Characteristics ).
Select the first mode by connecting MODE to VL. When
CTL is logic-high, Q1 turns on and Q2 turns off, con-
necting GON to SRC. When CTL is logic-low, Q1 turns
off and Q2 turns on, connecting GON to DRN. GON
can then be discharged through a resistor connected
between DRN and GND or AV
DD
. Q2 turns off and
stops discharging GON when V
GON
reaches 10 times
the voltage on THR.
MODE
CTL
DLP
SRC
GON
DRN
V
REF
SUI DONE
8μA
REF
Q1
Q4
Q3
R
2R
R
50μA
SWITCH CONTROL
THR
9R
R
VL
VL /2
1.25kΩ
SHDN
FAULT
Q5
MAX17113
6kΩ
Q2
Figure 5. Switch Control