NCP1607BDR2G ON Semiconductor, NCP1607BDR2G Datasheet - Page 9

• Manufacturer Part Number: NCP1607BDR2G
• Description: IC PFC CONTROLLER CRM 8SOIC
• Manufacturer: ON Semiconductor

Specifications of NCP1607BDR2G

• Mode: Critical Conduction (CRM)
• Current - Startup: 23.5µA
• Voltage - Supply: 9.5 V ~ 20 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Switching Frequency: 70 KHz
• Maximum Power Dissipation: 450 mW
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Introduction
(PFC) controller designed to drive cost effective
pre−converters to meet input line harmonic regulations.
This controller operates in critical conduction mode
(CRM) for optimal performance in applications up to
250 W. Its voltage mode scheme enables it to obtain unity
power factor without the need for a line sensing network.
The output voltage is accurately controlled by a high
precision error amplifier. The controller also implements a
comprehensive array of safety features for robust designs.
The key features of the NCP1607 are as follows:
•
•
•
•
•
•
•
•
The NCP1607 is a voltage mode power factor correction
Constant on time (Voltage Mode) CRM operation.
High power factor ratios are easily obtained without
the need for input voltage sensing. This allows for
optimal standby power consumption.
Accurate and Programmable On Time Limitation. The
NCP1607 uses an accurate current source and an
external capacitor to generate the on time.
High Precision Voltage Reference. The error amplifier
reference voltage is guaranteed at 2.5 V ±1.6% over
process, temperature, and voltage supply levels. This
results in very accurate output voltages.
Very Low Startup Current Consumption. The circuit
consumption is reduced to a minimum (< 40 mA)
during the startup phase, allowing fast, low loss,
charging of V
gives a controlled undervoltage lockout level and
provides ample V
Powerful Output Driver. A Source 500 mA / Sink
800 mA totem pole gate driver is used to provide rapid
turn on and turn off times. This allows for improved
efficiencies and the ability to drive higher power
MOSFETs. Additionally, a combination of active and
passive circuitry is used to ensure that the driver
output voltage does not float high while V
its turn on level.
Programmable Overvoltage Protection (OVP). The
adjustable OVP feature protects the PFC stage against
excessive output overshoots that could damage the
application. These events can typically occur during
the startup phase or when the load is abruptly
removed.
Protection against Open Feedback Loop
(Undervoltage Protection). Undervoltage protection
(UVP) disables the PFC stage when the output voltage
is excessively low. This also protects the circuit in
case of a failure in the feedback network: if no voltage
is applied to FB because of a poor connection or if the
FB pin is floating, UVP is activated shutting down the
converter.
Overcurrent Limitation. The peak current is accurately
limited on a pulse by pulse basis. The level is
adjustable by modifying the current sense resistor. An
CC
. The architecture of the NCP1607
CC
hysteresis during startup.
CC
is below
http://onsemi.com
9
•
Application information
use a diode bridge rectifier and a bulk storage capacitor to
produce a dc voltage from the utility ac line (Figure 20).
This DC voltage is then processed by additional circuitry
to drive the desired output.
when the instantaneous ac voltage exceeds the capacitor
voltage. Since this occurs near the line voltage peak, the
resulting current draw is non sinusoidal and contains a very
high harmonic content. This results in a poor power factor
(typically < 0.6) and consequently, the apparent input
power is much higher than the real power delivered to the
load. Additionally, if multiple devices are tied to the same
input line, the effect is magnified and a “line sag” effect can
be produced (see Figure 21).
requirements necessitate control over the line current
harmonic content. To meet this need, power factor
correction is implemented with either a passive or active
circuit. Passive circuits usually contain a combination of
large capacitors, inductors, and rectifiers that operate at the
ac line frequency. Active circuits incorporate some form of
a high frequency switching converter that regulates the
AC Line Current
Most electronic ballasts and switching power supplies
This simple rectifying circuit draws power from the line
Increasingly,
integrated LEB filter reduces the chance of noise
prematurely triggering the overcurrent limit.
Shutdown Features. The PFC pre−converter is placed
in a shutdown mode by grounding the FB pin or the
ZCD pin. During this mode, the I
consumption is reduced and the error amplifier is
disabled.
AC Line Voltage
Figure 21. Typical Line Waveforms without PFC
Line
Rectified DC
AC
Figure 20. Typical Circuit without PFC
V
pk
0
0
Rectifiers
government
+
Line
Sag
Capacitor
Bulk
Storage
regulations
CC
Converter
current
and
utility
Load