NCP1010, NCP1011, NCP1012, NCP1013, NCP1014
PIN FUNCTION DESCRIPTION
Pin No.
(SOT−223)
Pin No.
(PDIP−7,
PDIP−7/Gull Wing)
Pin Name
1
1
VCC
−
2
NC
−
3
NC
2
4
FB
3
5
Drain
−
−
−
−
7
NC
4
8
GND
Function
Powers the Internal Circuitry
−
−
Feedback Signal Input
Drain Connection
−
−
The IC Ground
Description
This pin is connected to an external capacitor of typi-
cally 10 mF. The natural ripple superimposed on the
VCC participates to the frequency jittering. For im-
proved standby performance, an auxiliary VCC can be
connected to Pin 1. The VCC also includes an active
shunt which serves as an opto fail−safe protection.
−
−
By connecting an optocoupler to this pin, the peak
current setpoint is adjusted accordingly to the output
power demand.
The internal drain MOSFET connection.
−
This unconnected pin ensures adequate creepage
distance.
−
VCC 1
VCC
Vclamp*
IVCC
I?
Startup Source
Iref = 7.4 mA −
Drain
IVCC
+
UVLO
Management
High when VCC t 3 V
S
R
Q
Rsense
250 ns
L.E.B.
NC 2
4V
EMI Jittering
NC 3
18 k
Error flag armed?
FB 4
Overload?
65, 100 or
130 kHz
Clock
Reset
Set Flip−Flop Q
DCmax = 65%
Reset
Driver
VCC
−
+
0.5 V
+
Startup Sequence −
Soft−Start Overload
Drain
*Vclamp = VCCOFF + 200 mV (8.7 V Typical)
Figure 2. Simplified Internal Circuit Architecture
8 GND
7 NC
5 Drain
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