cs1501 Cirrus Logic, Inc., cs1501 Datasheet - Page 13

• Manufacturer Part Number: cs1501
• Description: Digital Power Factor Correction Control Ic
• Manufacturer: Cirrus Logic, Inc.

5.12
If the PFC output sense resistor, R
GND), the measured output voltage decreases at a slew rate of
about 2 V/s, which is determined by the ADC sampling rate.
The IC stops the gate drive when the measured output voltage is
lower than the measured line voltage. The IC resumes gate drive
switching when the current into the IFB pin becomes larger than
or equal to the current into the IAC pin and V
the peak of the line voltage (V
time of open/short loop protection for R
5.13 Internal Overtemperature Protection
An internal thermal sensor triggers a shutdown when the
temperature exceeds 135°C (nominal) on the silicon. The
sensor sends a signal to the core that supplies current to all
internal digital logic, cutting off power from them. Once the
temperature of the IC has dropped by 9°C (nominal), the
sensor resets, allowing power to the logic.
If the PFC input sense resistor R
the current reference signal supplied to the IC on pin IAC falls to
zero.
DS927PP6
Open/Short Loop Protection
rect(pk)
IAC
fails (open or short to GND),
IFB
). The maximum response
IFB
, fails (open or short to
is about 150s.
link
is greater than
5.14 Standby (STBY) Function
The standby (STBY) pin provides a means by which an
external signal can cause the CS1501 to enter a
non-operating, low-power state. The STBY input is intended to
be driven by an open-collector/open-drain device. Internal to
the pin, there is a pull-up resistor connected to the V
shown in Figure 22. Since the pull-up resistor has a high
impedance, the user may need to provide a filter capacitor (up
to 1000pF) on this pin.
When the STBY pin is not used, it is recommended that the pin
be tied to V
DD
Figure 22. STBY Pin Connection
(pulled high).
See Text
<1 nF
STBY
2
8
6
GND
VDD
600k
CS1501
CS1501
DD
pin as
13