AN8027, AN8037
s
Pin Descriptions (continued)
Pin No. Pin name
6
Out
I/O
O
Explanation
Output used to directly drive a power MOSFET.
A totem pole structure is adopted in this
output circuit.
The absolute maximum ratings for the output
current are:
Peak:
±1
A
DC:
±150
mA
Voltage Regulators
Equivalent Circuit
V
CC
6
7
V
CC
Power supply.
This pin monitors supply voltage and has the
threshold for the start, stop, OVP, and OVP
reset levels.
This pin is used in RM (remote), OVP (over-
voltage protection), and timer latch.
RM:
The IC is in remote operation if this pin is
short-circuited to the ground and the output
of the IC is turned off.
OVP:
When overvoltage signal of the power sup-
ply is detected and high is inputted to the ter-
minal, it turns off the internal circuit. At the
same time, it holds that condition (latch).
Timer latch:
It detects the output voltage fall due to the
overcurrent condition of the power supply
output through the current level inputted to
FB. When the I
FB
decreases under the current
of certain value, the charge current flows in
the capacitor which is connected to this ter-
minal. Then, when the capacitor is charged
up to the threshold voltage of the OVP, the
OVP works so that the IC could keep the op-
eration stop condition.
Connection for the photocoupler used for the
power supply output error-voltage feedback.
This input can decrease the photocoupler dark
current by about 200
µA.
7
8
SD
I
V
CC
OVP
Comp.
3.9 V
I
TIM
8
RM
Comp.
0.1 V
25
µA
9
FB
I
V
REF
V
FB
I
FB
9
6
PANASONIC [ PANASONIC SEMICONDUCTOR ]
