LYT2002-2005
DRAIN
(D)
REGULATOR
6 V
BYPASS
(BP)
+
-
FB
OUT
6 V
5 V
+
-
Reset
VILIMIT
D
Q
STATE
MACHINE
FEEDBACK
(FB)
VTH
tSAMPLE-OUT
ILIM
DCMAX
Drive
FAULT
AUTO-RESTART
OPEN-LOOP
FB
6.5 V
tSAMPLE-INPUT
THERMAL
SHUTDOWN
INDUCTANCE
CORRECTION
DCMAX
tSAMPLE-OUT
SAMPLE
DELAY
tSAMPLE-INPUT
OSCILLATOR
SOURCE
(S)
+
-
ILIM
SOURCE
(S)
VILIMIT
CONSTANT
CURRENT
Current Limit
Comparator
LEADING
EDGE
BLANKING
PI-7302-061214
Figure 2. Functional Block Diagram.
Pin Functional Description
E Package
(eSIP-7C)
DRAIN (D) Pin:
Power MOSFET drain connection. It also provides internal
operating current during start-up and in steady-state operation.
Exposed Pad
(On Back Side)
Internally
Connected to
SOURCE Pin
BYPASS (BP) Pin:
Connection point for the external 1 mF bypass capacitor connected to
the internally generated 6 V supply.
D Package (SO-8C)
FB 1
8 S
7 S
6 S
5 S
FEEDBACK (FB) Pin:
Controls switching of the power MOSFET during normal opera-
tion. This pin senses the AC voltage on the bias winding.
Input is used to regulate both the output voltage in CV mode
and output current in CC mode based on voltage across the
bias winding in the flyback portion of the switching cycle. The
internal inductance correction circuit uses voltage on the bias
winding during forward part of the switching cycle to sense the
bulk capacitor voltage.
BP 2
1 2 3 4 5
7
D 4
Exposed Pad (On Bottom)
Internally Connected to
SOURCE Pin
K Package
(eSOP-12B)
FB 1
12 S
11 S
10 S
9 S
SOURCE (S) Pin:
Connected to the MOSFET source and is used for high-voltage
power and control circuit common returns.
BP 2
NC 3
NC 4
8 S
D 6
7 S
PI-6906-051614
Figure 3. Pin Configuration.
2
Rev. B 09/15
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