NCP1606
http://onsemi.com
3
PIN FUNCTION DESCRIPTION
Pin Number Name Function
1 Feedback (FB) The FB pin makes available the inverting input of the internal error amplifier. A simple resistor divider
scales and delivers the output voltage to the FB pin to maintain regulation. The feedback information
is also used for the programmable overvoltage and undervoltage protections.
2 Control The regulation block output is available on this pin. A compensation network is placed between FB
and Control to set the loop bandwidth low enough to yield a high power factor ratio and a low THD.
3 Ct The Ct pin sources a 270 mA current to charge an external timing capacitor. The circuit controls the power
switch on time by comparing the Ct voltage to an internal voltage derived from the regulation block.
4 Current Sense
(CS)
This pin limits the pulse by pulse current through the switch MOSFET when connected as show in
Figure 1. When the voltage exceeds 1.7 V (A version) or 0.5 V (B version), the drive turns off. The
maximum switch current can be adjusted by changing the sense resistor.
5 Zero Current
Detection (ZCD)
The voltage of an auxiliary winding should be applied to this pin to detect the moment when the coil is
demagnetized for critical conduction mode operation. Ground ZCD to shutdown the part.
6 Ground (GND) Connect this pin to the pre−converter ground.
7 Drive (DRV) The powerful integrated driver is suitable to effectively switch a high gate charge power MOSFET.
8 V
CC
This pin is the positive supply of the IC. The circuit starts to operate when V
CC
exceeds 12 V (typ)
and turns off when V
CC
goes below 9.5 V (typ). After startup, the operating range is 10.3 V to 20 V.
MAXIMUM RATINGS
Rating Symbol Value Unit
Supply Voltage V
CC
−0.3 to 20 V
Supply Current I
CC
±20 mA
DRV Voltage V
DRV
−0.3 to 20 V
DRV Current I
DRV
−800 to 500 mA
FB Voltage V
FB
−0.3 to 10 V
FB Current I
FB
±10 mA
Control Voltage V
Control
−0.3 to 10 V
Control Current I
Control
−2 to 10 mA
Ct Voltage V
Ct
−0.3 to 6 V
Ct Current I
Ct
±10 mA
CS Voltage V
CS
−0.3 to 6 V
CS Current I
CS
±10 mA
ZCD Voltage V
ZCD
−0.3 to 10 V
ZCD Current I
ZCD
±10 mA
Power Dissipation and Thermal Characteristics
P suffix, Plastic Package, Case 626
Maximum Power Dissipation @ T
A
= 70°C
Thermal Resistance Junction−to−Air
D suffix, Plastic Package, Case 751
Maximum Power Dissipation @ T
A
= 70°C
Thermal Resistance Junction−to−Air
P
D
(DIP)
R
q
JA
(DIP)
P
D
(SO)
R
q
JA
(SO)
800
100
450
178
mW
°C/W
mW
°C/W
Operating Junction Temperature Range T
J
−40 to +125 °C
Maximum Junction Temperature T
J(MAX)
150 °C
Storage Temperature Range T
STG
−65 to 150 °C
Lead Temperature (Soldering, 10 s) T
L
300 °C
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
1. This device series contains ESD protection and exceeds the following tests:
Pins 1−6, 8: Human Body Model 2000 V per JEDEC Standard JESD22−A114E,
Machine Model Method 200 V per JEDEC Standard JESD22−A115−A
Pin 7: Human Body Model 2000 V per JEDEC Standard JESD22−A114E,
Machine Model Method 180 V per JEDEC Standard JESD22−A115−A
2. This device contains latch−up protection and exceeds ±100 mA per JEDEC Standard JESD78.
