NCP1611ADR2G ONSEMI [ON Semiconductor], NCP1611ADR2G Datasheet - Page 26

• Manufacturer Part Number: NCP1611ADR2G
• Description: Enhanced, High-Efficiency Power Factor Controller
• Manufacturer: ONSEMI [ON Semiconductor]

gradual decrease of V
discontinuity and limits the risk of false triggering.
Pin2 is also used to sense the line for feed−forward. A similar
method is used:
Thermal Shutdown (TSD)
and keeps the power switch off when the junction
temperature exceeds 150°C. The output stage is then
enabled once the temperature drops below about 100°C
(50°C hysteresis).
circuit is not reset, that is, as long as V
V
the upper one (150°C), thus ensuring that any cold start−up
will be done with the proper TSD level.
CC(RESET)
An internal thermal circuitry disables the circuit gate drive
The temperature shutdown remains active as long as the
− The V
− If V
reference.
condition and the loop gain is divided by three (the
internal PWM ramp slope is three times steeper)
pin2
. The reset action forces the TSD threshold to be
SENSE
Vsense pin
exceeds 2.2 V, the circuit detects a high−line
pin voltage is compared to a 2.2 V
CONTROL
avoids a line current
CC
Figure 69. Input Line Sense Monitoring
is higher than
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26
until V
gain control for universal (wide input mains) applications.
to generate the current information required for the
frequency fold−back function.
Output Drive Section
minimize the cross conduction current during high
frequency operation. The gate drive is kept in a sinking
mode whenever the Under−Voltage Lockout is active or
more generally whenever the circuit is off (i.e., when the
“Fault Latch” of the block diagram is high). Its high current
capability (−500 mA/+800 mA) allows it to effectively
drive high gate charge power MOSFET. As the circuit
exhibits a large V
At startup, the circuit is in low−line state (“LLine” high”)
The line range detection circuit allows more optimal loop
As portrayed in Figure 69, the pin 2 voltage is also utilized
The output stage contains a totem pole optimized to
− Once this occurs, if V
25 ms, the circuit detects a low−line situation
(500 mV hysteresis).
pin2
exceeds 2.2 V.
CC
range (up to 35 V), the drive pin voltage
pin2
remains below 1.7 V for